Note: Descriptions are shown in the official language in which they were submitted.
CA 02777917 2015-09-24
MINIATURE SLUDGE LANCE APPARATUS
BACKGROUND OF THE INVENTION
Field of the Invention
[0002] This invention relates to a cleaning device for a steam generator and,
more
specifically, to a miniature sludge lance structured to pass between adjacent
tubes in the
steam generator.
Description of the Prior Art
[0003] A pressurized water nuclear reactor utilizes a steam generator to
maintain
separation of the water that passes over the nuclear fuel (the "primary
water") and the
water that passes through the electricity generating turbines (the "secondary
water"). The
steam generator has an outer shell defining an enclosed space, at least one
primary fluid
inlet port, at least one primary fluid outlet port, at least one second fluid
inlet port, at least
one second steam outlet port, and a plurality of substantially uniformly sized
tubes
extending between, and in fluid communication with, the at least one primary
fluid inlet
port and at least one primary fluid outlet port. That is, the primary water
passes through a
manifold that divides the primary water into multiple streams that pass
through the
plurality of tubes. This manifold may be located inside or outside of the
steam generator
shell, but is preferably disposed inside the steam generator shell. The
secondary water may
also pass through a manifold, or simply multiple inlets/outlets, but is
typically passed
through a single inlet and a single outlet. A typical steam generator is
cylindrical, about
sixty feet tall and about twelve feet in diameter.
[0004] The tubes are disposed in a substantially regular pattern extending
substantially vertically and having substantially uniform, narrow gaps between
adjacent
tubes. Further, the tubes typically have an overall shape of an inverted "U"
and are
coupled
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
to a flat plate having a plurality of opening therethrough. This flat plate,
or tube sheet, along
with another plate that separates the at least one primary fluid inlet port
and at least one
primary fluid outlet port, substantially forms the manifold noted above. Thus,
within the
stream generator shell, the tubes have an ascending side (hot) and a
descending side (cool).
Between these two sides there is a gap identified as the "tube lane." The
steam generator
shell has openings at various elevations and on either side of the tube lane.
Typically, the
openings are disposed in opposing pairs. A six inch diameter penetration for
opening at the
tube lane axis is typical. Since the tube lane is formed by the dome of U-
shaped tubes, access
to the center of the steam generator is generous along the tube lane.
[0005] In operation, the primary water is communicated through the tubes and
the
secondary water passes over the tubes. As this occurs, the secondary water is
heated and the
primary water is cooled. During operation of the pressurized water reactor
steam generator,
sediment is introduced on the secondary side as the secondary water changes to
steam. This
particulate sediment, or sludge, is deposited on most exposed surfaces
including on the outer
surface of the tubes and, primarily, on the top of the tube sheet. Periodic
cleaning of the
sediment is desirable to maintain good heat transfer and water flow in the
steam generator. A
typical cleaning is performed by sweeping high pressure and high volume water
jets
introduced along the tube lane axis of the steam generator where there is
ample clearance.
That is, a "lance" structured to spray high pressure water is moved through
the blithe lane and
is structured to spray water generally laterally (i.e. generally perpendicular
to the axis of the
tube lane) and downwardly in between the tubes. This spray lifts most of the
slUdge off the
tube sheet and removes sludge from the exposed sides of the tubes. The
cleaning can be
preceded by chemical treatment. This cleaning pattern, however, may leave
sludge between
the close pattern of tubes and is less effective at locations spaced from the
tube lane.
[0006] It is further noted that, in order to regulate secondary side water
flow patterns
in the steam generator, devices called tube lane blocks have been installed in
sortie steam
generators. The tube lane blocks can prohibit access for cleaning equipment
through the six
inch penetration. Support plate structures (stay rods) located within the tube
buudles of
steam generators are other obstructions that can prevent effective cleaning.
Due to various
internal physical restrictions in the tube lane (the area generated along the
centerline of the
tube sheet by the minimum bend radius of the Row 1 tubes), the tube sheet legs
(either hot or
cold depending on the location of the inlet nozzle) cannot be adequately
cleaned by
conventional lancing equipment mounted to the hand holes. Access to the tube
bundle is
2
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
further restricted by an arrangement of Tube Lane Blocking Devices (TLBD's)
and a
B lowdown Pipe positioned directly along the centerline of the hand hole in
the tube lane.
[0007] In addition to tube lane access, some steam generators have smaller
inspection penetrations, openings about two inches in diameter, located at
various
orientations and elevations about the steam generator. After entrance through
an inspection
penetration, access is limited by the gap between adjacent tubes. These
openings are not
typically used for cleaning because the problem is to accurately position and
sweep high
pressure cleaning jets and deliver high water volume within the confines of
adjacent tube
spacing and the inspection penetration. These penetrations can also be
disposed several
degrees from the center of the tube lane. Sludge lancing is typically not
performed through
these penetrations due to their physical size and location. Therefore, the
tube lane in these
steam generators is basically inaccessible and prone to accumulating sludge
and debris under
the blowdown pipe and between the TLBD's. In addition, certain utilities have
forbidden
hand-lancing with static jets that impinge directly on the tube sheet and
adjacent steam
generator tubing - this limits certain types of manual lancing that could be
employed through
the inspection penetrations to clean this region. Sludge lancing technicians
are subjected to
higher doses or radiation with equipment that does not provide an automated
mechanical
means of oscillation or rotation of the high velocity jets down the tube gaps.
[0008] It is further noted that, during steam generator cleaning (tube lane or
inspection port access) high pressure and volume water is injected into the
steam generator
and is sprayed laterally relative to the longitudinal axis of the lance. That
is, the water must
be redirected 90 degrees to clean between tubes. Water turbulence from a 90
degree bend
significantly increases the divergence of the exiting water jet.
SUMMARY OF THE INVENTION
[0009] Cleaning of the tube sheet and the outer surface of the tubes, or
"sludge
lancing," can be accomplished efficiently and, essentially, automatically
through the
inspection ports by introducing a cleaning tool, or "lance," through the
inspection
penetrations that are narrower than the tube gap (the space between adjacent
tubes that are a
function of the tube diameter and pitch). Providing, of course, that the lance
can be aligned
with a tube row and that the lance may be positioned to spray the high
velocity jet generally
parallel to the tube sheet. The inspection port lancing system disclosed below
has the
capability of being automatically indexed relative to tube bundle spacing and
in one
3
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
embodiment includes a simulated jet oscillation feature that translates rotary-
to-linear motion
for a high velocity lancing head suspended at the tube sheet level. This
system reduces the
time required to perform the sludge lancing, thus lowering the radiological
dose.
[0010] The disclosed and claimed concept provides generally for a sludge lance
structured to pass through the narrow tube gaps. The sludge lance includes a
nozzle assembly
having lateral nozzles. Thus, as the nozzle assembly is indexed, i.e. advanced
a distance
equal to a multiple of the tube gap spacing, a fluid may be sprayed through
the tube gap
cleaning adjacent tubes.
[0011] Preferably, the nozzle assembly includes multiple lateral nozzles
spaced
about a tube gap width apart. "Lateral nozzles" are structured to spray
perpendicular to the
longitudinal axis of the sludge lance. That is, as the sludge lance advances
between two rows
of tubes, the nozzles spray laterally thereby cleaning the two rows and
several rows beyond.
In this configuration, the nozzle assembly may be indexed multiple tube gaps
between
cleaning sprays. For example, if there are three nozzles, the nozzle assembly
may spray
between the first three tube gaps, then advance/index to the fourth-sixth tube
gaps and spray
again. Alternately, regardless of how many nozzles are on the nozzle assembly,
the sludge
lance may index one tube gap length at a time, thereby causing each tube gap
(except the last)
to be washed multiple times.
[0012] The disclosed and claimed concept further includes a segmented rail.
The rail
defines the passage through which the water, or other cleanser, passes prior
to the nozzle
assembly. The oval geometry of the water passage, and associated end seals,
enables high
fluid flow. Lower placement of the water passage balances the coupling loads
and eliminates
the need for internal support structures. The rail also includes a drive shaft
structured to
move the nozzle assembly. The nozzle assembly is coupled to a first end of the
rail, the end
that is inserted into the steam generator. A water manifold is coupled to the
second end of
the rail, the end that remains outside of the steam generator. Further, an
oscillation assembly
is disposed at the rail second end and is structured to provide motion to the
drive shaft.
[0013] On one hand, it is desirable to have as few separate components
inserted into
the steam generator as that increases the chances of accidentally dropping a
component in the
steam generator. Thus, if there is only a single inspection opening, rather
than opposed
openings, at a certain orientation and elevation on the steam generator shell,
a rail may be,
essentially, as long as the diameter of the steam generator. On the other
hand, steam
generators are often located in confined spaces wherein an extended rail could
not fit. Thus,
4
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
preferably, the rail is segmented. That is, a plurality of similar rail
assemblies are coupled
together to form the rail. The rail assemblies may be a uniform length, thus
reducing
manufacturing costs, or, may be a variety of lengths so as to reduce the
number of
components while still being useful in a confined space. For example, rail
assemblies having
lengths of five, three, and two feet could be used to form a rail having a
total length of ten
feet, but could still be manipulated in building providing a six foot space
about a steam
generator.
[0014] The rail is moved longitudinally by a drive assembly. The drive
assembly is
structured to support and precisely index the rail. The drive assembly is
disposed on a
mounting assembly coupled to the inspection opening. The mounting assembly has
an
alignment (adjustment) device that allows the rail to be properly aligned with
the tube gap
between two rows. It is noted that a small misalignment adjacent the
inspection opening may
result in the first end of the rail contacting tubes as the rail is advanced.
This is not desirable
as movement of the lance may be restricted.
[0015] There are two nozzle assembly embodiments disclosed herein. Both nozzle
assemblies may use the same rail and drive assembly, but each utilizes a
different type of
oscillatory motion. Thus, the oscillation assembly for each embodiment is
slightly different.
In one embodiment, oscillation is simulated by mechanically raising and
lowering the nozzle
assembly (containing the high velocity water jets) against the hydrostatic
operating pressure
developed by the jet geometry.
[0016] In another embodiment, the nozzle assembly is structured to rotate over
an arc
of 180 degrees. With opposing nozzles, this creates a spray covering 360
degrees. An anti-
backlash mechanism permits accurate nozzle sweep orientation. That is, when a
drive shaft
is segmented, there is the possibility of the segments not maintaining their
orientation relative
to each other due to tolerances at the couplings. This misalignment is
exacerbated when the
high pressure water is sprayed. This is a disadvantage as the nozzle assembly
must be
oriented properly so as to pass through the tube gaps
[0017] In this configuration, the miniature sludge lance provides quick,
accurate, and
repeatable setup.
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] A further understanding of the invention can be gained from the
following
description of the preferred embodiments when read in conjunction with the
accompanying
drawings in which:
[0019] Figure 1 is an isometric, cut away view of a steam generator.
[0020] Figure 2 is a top cross-sectional view of the steam generator of Figure
1.
[0021] Figure 3 is a detailed top cross-sectional view of the steam generator
showing
one embodiment of the miniature sludge lance.
[0022] Figure 4 is a detailed side cross-sectional view of the steam generator
showing one embodiment of the miniature sludge lance.
[0023] Figure 5 is a cross-sectional side view of a portion of the rail.
[0024] Figure 6 is a cross-sectional side view of the head assembly and one
embodiment of the nozzle assembly.
[0025] Figure 7 is a cross-sectional side view of a rail assembly.
[0026] Figure 8 is a cross-sectional side view of a portion of the oscillator
assembly
and the water manifold.
[0027] Figure 9 is a cross-sectional side view of the second end of a rail
assembly.
[0028] Figure 10 is a cross-sectional side view of the first end of a rail
assembly.
[0029] Figure 11 is a top view of the drive assembly.
[0030] Figure 12 is a side view of the drive assembly.
[0031] Figure 13 is a back end view of the drive assembly.
[0032] Figure 14 is a schematic side view of the drive assembly.
[0033] Figure 15 is a detailed side cross-sectional view of the steam
generator
showing the positioning assembly.
[0034] Figure 16 is an end view of the nozzle orientation reset device.
[0035] Figure 17 is a detailed side cross-sectional view of the steam
generator
showing another embodiment of the miniature sludge lance.
[0036] Figure 18 is a detailed side cross-sectional view of the retraction
assembly.
Figure 18A is a detail of a cross-section side view of the sliding head
assembly of Figure 18.
[0037] Figure 19 is a detailed side cross-sectional view of the other
embodiment of
the miniature sludge lance.
[0038] Figure 20 is a detailed side cross-sectional view of the other
embodiment of
the oscillator assembly.
6
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
[0039] Figure 21 is a detailed side cross-sectional view of a nozzle assembly.
[0040] Figure 22 is an end view of a flow straightener.
[0041] Figure 23 is a side view of the mounting assembly.
[0042] Figure 24 is an end view of the mounting assembly.
[0043] Figure 25 is a top view of the mounting assembly.
[0044]
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0045] As used herein, "coupled" means a link between two or more elements,
whether direct or indirect, so long as a link occurs.
[0046] As used herein, "directly coupled" means that two elements are directly
in
contact with each other.
[0047] As used herein, "fixedly coupled" or "fixed" means that two components
are
coupled so as to move as one while maintaining a constant orientation relative
to each other.
The fixed components may, or may not, be directly coupled.
[0048] As used herein, "temporarily coupled" means that two components are
coupled in a manner that allows for the components to be easily decoupled
without damaging
the components. "Temporarily coupled" components are easy to access or
otherwise
manipulate. For example, a nut on a bolt that is exposed is "temporarily
coupled" while a nut
on a bolt within a typical transmission case sealed by multiple fasteners is
not "temporarily
coupled."
[0049] As used herein, "correspond" indicates that two structural components
are
sized to engage each other with a minimum amount of friction. Thus, an opening
which
corresponds to a member is sized slightly larger than the member so that the
member may
pass through the opening with a minimum amount of friction.
[0050] As used herein, a "keyed coupling," a "keyed socket," a "keyed opening"
and
a "keyed end" mean that two components are structured to be temporarily fixed
together.
This may be accomplished by a fixed threaded connection or an extension or lug
disposed in
a bore or passage. The extension and socket have a cross-sectional shape that
correspond to
each other but are not circular. As such, the extension cannot rotate in the
socket. Keyed
elements may have a cross-sectional shape such as, but not limited to a
hexagon (such as a
common nut) a "D" shape, or a rectangle. Unless otherwise coupled, e.g. by
welding or
adhesive, or otherwise difficult to access, a keyed coupling provides a
temporary coupling.
7
CA 02777917 2016-06-02
W02011/078916
PCT/US2010/055207
[0051] As used herein, the word "unitary" means a component is created as a
single piece
or unit. That is, a component that includes pieces that are created separately
and then coupled
together as a unit is not a "unitary" component or body.
[0052] As used herein, a body moving in a "longitudinal direction" means that
the body
moves in a direction aligned with the body's longitudinal axis.
[0053] As used herein, "operatively engage" when used in reference to gears,
or other
components having teeth, means that the teeth of the gears engage each other
and the rotation of
one gear causes the other gear to rotate as well.
[0054] Figures 1 and 2 show a steam generator 10 associated with a pressurized
water
nuclear reactor (not shown). A more complete description of a steam generator
10 is set forth
in U.S. Patent Pub. 2008/0121194. Generally however, the steam generator 10
includes an
elongated, generally cylindrical shell 12 defining an enclosed space 14, at
least one primary
fluid inlet port 16, at least one primary fluid outlet port 18, at least one
second fluid inlet port
20, at least one second fluid outlet port 22, and a plurality of substantially
uniformly sized
tubes 24 extending between, and in fluid communication with, the at least one
primary fluid
inlet port 16 and at least one primary fluid outlet port 18. The cylindrical
shell 12 is typically
oriented with the longitudinal axis extending substantially vertically. The
tubes 24 arc
scalingly coupled to a tube sheet 23 that forms part of a manifold within the
enclosed space
that divides the fluid inlet port 16 and the fluid outlet port 18. As seen in
Figure 1, the tubes
24 generally follow a path shaped as an inverted "U." As seen in Figures 2 and
3, the tubes 24
are disposed in a substantially regular pattern having substantially uniform,
narrow gaps 25
between adjacent tubes 24. The tube gap 25 is typically between about 0.29 and
0.41 inches,
and more typically about 0.33 inches. Also, as shown, the "U" shape of the
tubes 24 creates a
tube lane 26 extending across the center of the shell 12. On both sides of the
tube lane 26
there is tube lane access opening 30. A tube lane access opening 30, which is
usually round,
typically has a diameter of between about five and eight inches, and more
typically about six
inches. Further, the shell 12 has at least one inspection opening 32 disposed
adjacent to said
plurality of tubes 24 that is not aligned with the tube lane 26. An inspection
opening 32,
which is usually round, typically has a diameter of between about one and a
half and four
inches, and more typically about two inches. It is noted that the tube lane
access opening 30
and inspection openings 32 can be located at multiple elevations on the shell
12.
8
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
[0055] During operation of the pressurized water nuclear reactor, heated,
primary
water from the reactor is passed through the tubes 24 via the at least one
primary fluid inlet
port 16 and removed from the steam generator 10 via the at least one primary
fluid outlet port
18. Secondary water, enters the steam generator 10 via the at least one second
fluid inlet port
20 and leaves the steam generator 10 via the at least one second steam outlet
port 22. As the
secondary water is passed over the outer surface of the tubes 24, the
secondary water is
converted to steam, leaving sludge between the tubes 24, on the tube sheet 23,
and on other
structures in the steam generator 10. Typically, access for a full sized
sludge lance (not
shown) is through the tube lane access opening 30.
[0056] As shown in Figures 3 and 4, a miniature sludge lance 50 includes a
mounting
assembly 52, a drive assembly 54, an elongated rail 56, a nozzle assembly 58,
and,
preferably, an oscillator assembly 60. The miniature sludge lance 50, unlike a
full sized
sludge lance, is structured to be inserted into the steam generator 10 via an
inspection
openings 32. Further, the portion of the miniature sludge lance 50 that passes
into the steam
generator 10, i.e. the rail 56 and nozzle assembly 58, is sized to pass
between adjacent tubes
24, i.e. pass through the tube gaps 25.
[0057] The mounting assembly 52 is structured to support the drive assembly 54
and
the rail 56. The drive assembly 54 is structured to move the rail 56 through
the inspection
opening 32. Further, the drive assembly 54 is coupled to the mount assembly
52. The rail 56
has a body 70 and a drive shaft 72 (Fig. 5). The rail body 70 has a first end
74 and a second
end 76. Generally, as used herein, the rail body first end 74 is the end that
is moved into the
steam generator 10. As shown in Figure 5, the rail body 70, as noted above, is
sized to pass
between adjacent tubes 24. The rail body 70 defines a water passage 78 and a
drive shaft
passage 80. The drive shaft 72 is rotatably disposed in the drive shaft
passage 80. The rail
body 70 is movably coupled to the drive assembly 54. The rail water passage 78
is structured
to be coupled to, and in fluid communication with, a water supply (not shown),
which is
preferably a high pressure water supply. It is noted that the water may
include a cleanser, or
the fluid may be only a cleanser. As used herein, "water" means the fluid used
to clean the
tubes 24.
[0058] As shown in Figure 6, the nozzle assembly 58 has a body assembly 400,
500
(Fig. 19) which, as noted above, is sized to pass between adjacent tubes 24.
The nozzle
assembly body assembly 400, 500 also defines a water passage 401. The nozzle
assembly
body assembly 400, 500 is coupled to the rail body 70 with the nozzle assembly
body
9
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
assembly water passage 401 being in fluid communication with the rail body
water passage
78. In this configuration, as the rail body 70 is moved through the inspection
opening 32, the
nozzle assembly 58 passes between adjacent tubes 24. As the nozzle assembly 58
passes
between adjacent tubes 24 and one purpose of the miniature sludge lance 50 is
to clean
multiple tubes 24, the water is preferably sprayed generally laterally, that
is in a direction
generally perpendicular to the longitudinal axis of the rail 56. More
preferably, the water is
sprayed at a slight downward angle so as to impinge upon sludge on the top of
the tube sheet
23. Thus, the nozzle assembly body assembly 400, 500 is, preferably, elongated
and
includes at least two lateral nozzles 600. Preferably, the at least two
lateral nozzles 600 are
spaced longitudinally from each other on the nozzle assembly body assembly
400, 500, and,
more preferably, the nozzles 600 are spaced substantially the same distance as
between the
centerline of two adjacent tubes 24, i.e. same distance as between the
centerline of adjacent
tube gaps 25. Further, the nozzle assembly 58 may include four nozzles 600,
with the
nozzles 600 disposed in opposing pairs. In this configuration the nozzles 600
in a pair face
substantially opposite directions. Thus, the water is sprayed in two
directions. The nozzle
assembly 58 may be positioned at different tube gaps 25 and actuated. That is,
the nozzle
assembly 58 may spray high pressure water through the tube gaps 25 thereby
cleaning the
tubes 24 immediately adjacent the nozzle assembly 58 as well as several rows
of tubes 24
therebeyond.
[0059] The miniature sludge lance 50 may utilize at least two different types
of
nozzle assemblies 58. Each of these nozzle assemblies 58, a rotating nozzle
assembly 58A
and a vertically reciprocating nozzle assembly 58B (Fig. 19)are detailed
below. Each type of
nozzle assembly 58A, 58B have an associated oscillator assembly 60A, 60B. The
remaining
components of the miniature sludge lance 50 may be used with any nozzle
assembly 58.
Accordingly, the following description shall address the common components
first, then
discuss the two types of nozzle assemblies 58A, 58B.
[0060] As noted above, the rail 56 has a body 70 and a drive shaft 72. The
rail body
70 has a first end 74 and a second end 76. The rail body 70 is substantially
rigid. The rail
body 70 is sized to pass between adjacent tubes 24. The corners of the rail
body 70 may be
chamfered to reduce the chance of a sharp edge contacting the tubes 24.
Preferably, the rail
body 70 has a rectangular cross-sectional shape having a greater height than
width. This
configuration, as compared to another shape, e.g. a circular cross section,
allows for the rail
body water passage 78 to be larger so as to provide a sufficient amount of
water. It is further
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
noted that the rail body water passage 78, preferably, has an oval cross-
sectional shape. This
shape allows for a less turbulent flow as the water passes into the nozzle
assembly 58. The
rail body drive shaft passage 80 is, preferably, generally circular. The drive
shaft 72 is
generally circular. The drive shaft 72 has a first end 82 (Figure 6) and
second end 84 (Fig.
8). The drive shaft first and second ends 82, 84 are, preferably, a keyed
coupling (key and
keyed socket 134, 136, discussed below) or coupled to a key for a keyed
coupling, as
discussed below.
[0061] The rail body 70 has a sufficient length to reach all tubes 24 in a
steam
generator. Thus, if the steam generator shell 12 is ten feet in diameter, and
every inspection
opening 32 has an opposing inspection opening 32, the rail body 70 would be
about five feet
long. If the steam generator shell 12 is ten feet in diameter, and the
inspection openings 32
do not have an opposing opening, the rail body 70 would be about ten feet
long.
[0062] Steam generators 10, however, are not always disposed in a facility
with a ten
foot, or greater, clearance about the steam generator 10. Thus, the rail 56
may be segmented.
That is, the rail 56 may include modular rail assemblies 90 and a water
manifold 92 as shown
in Figures 7 and 8. The rail assemblies 90 are structured to be coupled
together and to be
coupled to the water manifold 92 so as to form the rail 56. Thus, selected
components to the
rail 56, e.g. the drive shaft second end 84 are shown as part of selected
assemblies. Each rail
assembly 90 has a drive shaft segment 94 and an elongated body 96. As before,
each rail
assembly body 96 is elongated and has a first end 98 and a second end 100.
Further, each rail
assembly body 96 has a, preferably, rectangular cross section that defines a,
preferably oval,
water passage 99 and a generally circular drive shaft passage 101. Each rail
assembly body
96 is sized to pass between adjacent tubes 24.
[0063] Further, each rail assembly body 96 includes a water passage seal 102.
The
rail assembly body water passage seal 102 may be disposed at either, or both,
rail assembly
body ends 98, 100, but is preferably disposed at the rail assembly body first
end 98. That is,
for each rail assembly body 96 there is an associated seal 102 at the rail
assembly body first
end 98. When the rail assembly bodies 96 are coupled together, as described
below, the each
water passage seal 102 is structured to sealingly engage the adjacent rail
assembly body 96.
Each water passage seal 102 is, preferably, disposed in a recess 104 in the
axial face of the
rail body first end 74. The seal recess 104 extends about the rail body water
passage 78 and
provides support for the water passage seal 102. Further, a seal support frame
106 may be
disposed in the seal recess 104 to provide additional support to the seal 102.
Further, each
11
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
rail assembly body 96 may have a longitudinal window 108 therein. The
longitudinal
window 108 is aligned with, and provides communication with, the drive shaft
passage 101.
The longitudinal window 108 allows for easier manufacture of the drive shaft
passage 101
(reduces the length the drive shaft passage 101 must be cut from each end of
the rail
assembly body 96), allows for holding the drive shaft segment 94 when coupling
threaded
drive shaft segments 94, and allows a user to observe the drive shaft segment
94 during use.
[0064] Each rail assembly body 96, preferably, has a substantially uniform
length of
between about 6.0 and 24.0 inches, and more preferably about 10.0 inches.
Preferably, each
rail assembly body 96 has a length in a multiple of the tube pitch. This
allows
interchangeability of rail assemblies 90. That is, for each steam generator 10
model (wherein
the tube 24 spacing is substantially uniform) the rail assembly body 96 length
being a
multiple of the tube pitch allows for the spacing of the sprocket holes 200
and the positioning
indicia 308, both discussed below, to be uniformly spaced on each rail
assembly body 96.
Alternatively, the rail assembly bodies 96 may have notably different lengths
sized so as to
minimize the number of rail assembly bodies 96 required to extend across the
steam
generator 10 while sized to fit within the facility in which the steam
generator 10 is located.
For example, for a steam generator 10 ten feet in diameter, the rail assembly
bodies 96 may
have lengths of five, three, and two feet.
[0065] As shown in Figure 8, the water manifold 92 is structured to be coupled
to,
and in fluid communication with, a water supply (not shown), and preferably a
high pressure
water supply (not shown). The water manifold 92 has a drive shaft segment 110
and a body
112. The water manifold body 112 has a first end 114 and a second end 116. The
water
manifold body 112 defines a water passage 118 and a drive shaft passage 120.
The water
manifold body first end 114 is coupled to the second end 100 of the rail
assembly body 96
disposed at the rail body second end 76. That is, as noted above the rail body
second end 76
is the end of the rail body 70 that is located outside of the steam generator
10. Thus,
regardless of how many rail assemblies 90 are used to form the rail 56, the
water manifold 92
is coupled to the rail assembly body 96 at the rail body second end 76.
[0066] As noted above, the drive shaft 72 is an elongated, substantially
cylindrical
body structured to rotate in the drive shaft passage 80. When the drive shaft
72 is divided
into drive shaft segments 94, as shown in Figure 7, the drive shaft segments
94 are structured
to be temporarily fixed to each other by couplings. That is, each drive shaft
segment 94 has a
first end 130 and a second end 132. The drive shaft segment ends 130, 132 are
either an
12
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
extension 134 or a socket 136; depending upon the nozzle assembly 58A, 58B
used, each
drive shaft segment first end 130 is either a key, such as a keyed extension
134A or a
threaded extension 134B and each drive shaft segment second end 132 is either
a keyed
socket 136A or a threaded socket 136B. Further, as shown in Figure 8, the
water manifold
drive shaft segment 110 has a first end 140 and a second end 142, both of
which are either a
keyed extension 134A or a threaded extension 134B, depending upon the type of
drive shaft
72 in use. That is, the water manifold drive shaft segment first end 140
corresponds to the
type of drive shaft segment socket 136 in use. When the rail body 70 is
segmented, the
water manifold drive shaft segment second end 142 is the drive shaft second
end 84 as the
water manifold drive shaft segment second end 142 is always located at the
rail body second
end 76. Thus, all drive shaft segments 94 and the water manifold drive shaft
segment 110
may be temporarily fixed to each other to form the drive shaft 72.
10067] As detailed below, the drive shaft 72 is, preferably, structured to
move in a
longitudinal direction. As shown in Figures 9 and 10, this is assisted by at
least one bearing
150 disposed between the drive shaft 72 and the rail body drive shaft passage
80. When the
rail body 70 is segmented, there is at least one bearing 150 disposed between
each drive shaft
segment 94 and each rail assembly body drive shaft passage 101. More
preferably there are
two bearings 150 in each rail assembly body 96, one adjacent each drive shaft
segment end
130, 132. The at least one bearing 150 is maintained in the desired location
adjacent each
drive shaft segment end 130, 132 by fixing the bearing to the rail assembly
body 96 by a
spring pin 153. Further, each drive shaft segment 94 includes at least one
reduced diameter
portion 152, and preferably one reduced diameter portion 152 per bearing 150.
Each reduced
diameter portion 152 forms a channel in which the bearing 150 is disposed. The
ends of each
reduced diameter portion 152 prevents the bearing 150 from moving beyond the
reduced
diameter portion 152. Because at least one bearing 150 is fixed in place
relative to the rail
assembly body 96, this has the effect of trapping the drive shaft segment 94
in the rail
assembly body 96. More preferably, the reduced diameter portion 152 is longer
than the
associated bearing 150 thereby allowing the the drive shaft segment 94to move
a small
distance longitudinally relative to the rail assembly body 96.. Each at least
one bearing 150
has a length and each drive shaft segment reduced diameter portion 152 has an
axial length
that is greater than the at least one bearing 150 length. Preferably, with
regard to the first
embodiment discussed below, the relative lengths of the bearing 150 and the
reduced
diameter portion 152 allows the drive shaft segment 94 to move between 0.125
inch to 0.375
13
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
inch, and more preferably about 0.25 inch. It is noted that, for the second
embodiment
discussed below, the drive shaft segments 94 are structured to shift between
about 1.0 inch
and 2.0 inches, and more preferably about 1.25 inches.
[0068] Each rail assembly body 96 has a coupling assembly 160 disposed at each
end
98, 100. Each rail body coupling assembly 160 is substantially the same so
that any two rail
bodies 70 may be coupled to each other. That is, each rail body coupling
assembly 160 has a
first component 162 and a second component 163. Each rail assembly body first
end 98 has a
coupling assembly first component 162 and each rail body second end 100 has a
coupling
assembly second component 163. Thus, the rail assembly bodies 96 may be
coupled in
series. Preferably, each coupling assembly first component 162 is at least one
threaded
fastener 164 and each coupling assembly second component 163 is at least one
threaded bore
166. The at least one threaded fastener 164 is disposed in an elongated pocket
165 that
extends generally longitudinally at the rail assembly body first end 98. A
retaining body 167
may be disposed in the elongated pocket 165 and held in place by a spring pin
153. The
retaining body 167 prevents the at least one threaded fastener 164 from being
removed from
the elongated pocket 165, thereby reducing the chance of a component falling
into the steam
generator 10.
[0069] One nozzle assembly 58A utilizes a head assembly 170 disposed at the
rail
body first end 74, as shown in Figure 6. It is noted that if alternate nozzle
assemblies 58A,
58B are not to be used, the elements of the head assembly 170 could be
incorporated into the
rail body 70. Thus, it is understood that the components described in relation
to the head
assembly 170 may also be considered to be part of the rail body 70. The head
assembly 170
is structured to movably support the nozzle assembly 58A, as detailed below.
The head
assembly 170 has a body 172 with a first end 174 and a second end 176. The
head assembly
body 172 defines a, preferably oval, water passage 178 and a, generally
circular, drive shaft
passage 180. The head assembly body 172 is sized to pass between adjacent
tubes 24. The
head assembly body second end 176 is structured to be, and when assembled is,
coupled to
the first end 98 of the rail assembly body 96 disposed at said rail first end
74. That is, just as
the water manifold 92 is disposed at the back end, i.e. the second end 76, of
the rail 56, the
head assembly 170 is disposed at the forward end, i.e. the first end 74, or
the rail 56. Further,
the head assembly body water passage 178 and drive shaft passage 180 are
sized, shaped, and
located to match with the rail body water passage 78 and rail body drive shaft
passage 80, or,
the adjacent rail assembly body water passage 99 and rail assembly body drive
shaft passage
14
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
101. Further, the rail assembly body water passage seal 102 is structured to
seal against the
head assembly body 172. In this configuration, the head assembly body 172, the
at least one
rail assembly body 96 and the water manifold body 112 define the elongated
rail water
passage 78 and a drive shaft passage 80.
[0070] As noted above, the rail body 70, or the rail assembly bodies 96, are
elongated and preferably have a rectangular cross-section. Thus, the rail body
70, or the rail
assembly bodies 96, have two wide sides, hereinafter an outer face 190 (Fig.
3) and an inner
face 192 (Fig. 3), and two narrow lateral sides 194, 196 (Fig. 4). One rail
body lateral side
194 has a plurality of sprocket holes 200 (Fig. 5). When the rail 56 is formed
from rail
assembly bodies 96, the sprocket holes 200 maintain a consistent spacing over
the interface
between adjacent rail assembly bodies 96. The other rail body lateral side 196
is preferably,
generally smooth. The sprocket holes 200 are structured to be engaged by the
drive assembly
54.
[0071] As shown in Figures 11-13, the drive assembly 54 has a motor 210, a
housing
assembly 212, and a non-slip drive 213 and at least one guide surface 216. The
non-slip
drive 213 may be, but is not limited to, a gear system or a rack and pinion
(not shown), but is
preferably a drive sprocket 214. The motor 210 has an output shaft 218 and the
drive
assembly motor 210 is structured to rotate the drive assembly output shaft
218. The output
shaft 218 is coupled to the drive sprocket 214. The at least one guide surface
216 is
structured to maintain the rail body 70, or the rail assembly bodies 96, in
contact with the
drive sprocket 214. The rail body 70 is, or the rail assembly bodies 96 are,
disposed between
the guide surface 216 and the sprocket 214 with the sprocket holes 200
engaging the sprocket
pins 215. Preferably, the sprocket pins 215 are involute. The drive assembly
housing
assembly 212 includes an upper case 220 and a lower case 222. The upper case
220 and the
lower case 222 are movably coupled to each other and structured to translate
relative to each
other. More preferably, the upper case 220 and the lower case 222 are
structured to move
over a single axis in substantially the same plane, i.e. the upper case 220
and the lower case
222 translate in a plane while moving over a single axis.
[0072] As shown in Figure 14, to accomplish this controlled motion of the
upper
case 220 and the lower case 222, the drive assembly housing assembly 212
includes two
elongated guide pin passages 224 and two elongated guide pins 226. The guide
pin passages
224 extend through both the upper case 220 and the lower case 222. That is,
the guide pin
passages 224 are bifurcated and aligned on each of the upper case 220 and the
lower case
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
222. The guide pin passages 224 longitudinal axes are disposed in the same
plane and
extend substantially parallel to each other. Preferably, the guide pin
passages 224 include a
linear bearing 225 disposed in the lower case 222 guide pin passage 224.
Further, the lower
case 222 guide pin passage 224 preferably includes a threaded portion 227 and
the guide pins
226 have corresponding threads 228, thereby allowing the guide pins 226 to be
coupled to
that passages 224. The guide pins 226 are disposed in the guide pin passages
224 and are,
preferably, coupled to the lower case 222.
[0073] Further, the upper case 220 and the lower case 222 are structured to be
biased
toward each other. This bias causes components coupled to the upper case 220
and the lower
case 222 to engage the lateral sides 194, 196 of the rail body 70. The bias
may be affected by
a device such as a tension spring coupled to both the upper case 220 and the
lower case 222,
but is preferably affected by a biasing assembly 230 on one guide pin 226. The
guide pin
biasing assembly 230 includes a biasing device 232, a knob 234, and a threaded
end 236 on
the associated guide pin 226. Further, the associated guide pin passage 224
has a portion 238
with a wider diameter whereby, when the guide pin 226 is disposed in the guide
pin passage
224 having a portion 238 with a wider diameter, an annular space 240 is
created. The guide
pin passage 224 having a portion 238 with a wider diameter is, preferably,
disposed in the
upper portion of the bifurcated guide pin passage 224. The biasing device 232,
which is
preferably a compression spring 242, is disposed in the annular space 240. The
guide pin
threaded end 236 is disposed adjacent the upper case 220. That is, the guide
pin threaded end
236 is in the upper portion of the bifurcated guide pin passage 224. The knob
234 has a
threaded opening 244. The knob 234 is disposed on the guide pin threaded end
236. In this
configuration, the biasing device 232 is disposed between the bottom of the
annular space
240 and the knob 234. This configuration causes the biasing assembly 230 to
biases the
upper case 220 and the lower case 222 toward each other.
[0074] To accomplish the desired effect of components coupled to the upper
case
220 and the lower case 222 engaging the lateral sides 194, 196 of the rail
body 70, the drive
sprocket 214 and the at least one guide surface 216 must be coupled to
different portions of
the drive assembly housing assembly 212. While the positions could be
reversed, in the
embodiment shown in the figures, the drive sprocket 214 is rotatably coupled
to the lower
case 222 and the at least one guide surface 216 is disposed on the upper case
220. In this
configuration, the drive sprocket 214 and the at least one guide surface 216
engage opposing
lateral sides 194, 196 of rail body 70. While the at least one guide surface
216 may be a cam
16
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
surface, in the preferred embodiment, the at least one guide surface 216 is at
least one guide
wheel 250 rotatably attached to the upper case 220. For a greater degree of
control of the rail
body 70, the at least one guide wheel 250 may have three guide wheels 250.
Preferably, the
guide wheels 250 and the sprocket 214 (not the teeth 215 of the sprocket) have
substantially
the same diameter. The axes of the three guide wheels 250 and the sprocket 214
are disposed
in a substantially rectangular pattern. This configuration effectively creates
a longitudinal
path through which the rail body 70 passes. It is noted that, if the guide
wheels 250 and/or
the sprocket 214 have different diameters, the same effect may be accomplished
by three
guide wheels 250 and the sprocket 214 being disposed in a quadrilateral
pattern.
[0075] A system of guide wheels 250 is preferred over a cam surface so as to
reduce
wear and tear on the sides of the rail body 70 as the rail body 70 must be
acted upon
repeatedly by the guide wheels 250 and the sprocket 214. Wear and tear may be
further
reduced by causing at least the guide wheel 250 vertically opposing the
sprocket 214 to rotate
at the same rate as the sprocket. This is accomplished by a drive assembly
gear assembly 260
that is coupled to the sprocket 214 and structured to rotate the at least one
guide wheel 250.
The drive assembly gear assembly 260 includes a first gear 262, a second gear
264, a third
gear 266, a fourth gear 268, a first elongated link 270 and a second elongated
link 272. The
first gear 262 is fixed to the sprocket 214 and shares the same axis of
rotation. The second
gear 264 fixed to the at least one guide wheel 250. The first link 270 has a
first end 274 and a
second end 276. The first link 270 is sized to rotatably support the first
gear 262, the third
gear 266 and the fourth gear 268 in engagement. That is, the first link 270 is
long enough so
that the first gear 262, the third gear 266 and the fourth gear 268 may be
rotatably mounted
thereon, but not so long that the first gear 262, the third gear 266 and the
fourth gear 268 fail
to operatively engage each other. The second link 272 has a first end 278 and
a second end
280. The second link 272 is sized to support the second gear 264 and the
fourth gear 268 in
operative engagement. The first link first end 274 is rotatably coupled to the
lower case 222
with an axis of rotation corresponding to the sprocket 214 axis of rotation.
The second link
first end 278 is rotatably coupled to the upper case with an axis of rotation
corresponding to
the at least one guide wheel 250 axis of rotation. Further, the first link
second end 276 and
the second link second end 280 are rotatably coupled together and share an
axis of rotation
with the fourth gear 268. In this configuration, the drive assembly gear
assembly 260 is
structured to maintain the gears 262, 264, 266 , 268 in operative engagement
at the two links
270, 272 and rotate relative to each other about the second end 276, 280
joint. The two links
17
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
270, 272 rotate relative to each other about the second end 276, 280 joint as
the upper case
220 and the lower case 222 move as described above. Thus, in this
configuration, regardless
of the spacing between the upper case 220 and the lower case 222, the sprocket
214 and the at
least one wheel 250 remain operatively coupled via the operative engagement of
the gears
262, 264, 266 , 268.
[0076] Having described the drive assembly 54 and elongated rail 56 it can be
seen
that the rail 56 passes through the path between the drive assembly sprocket
214 and guide
wheels 250 while the rail 56 is engaged by the sprocket 214. As the drive
assembly motor
210 rotates the sprocket 214, the rail 54 is moved in or out of the steam
generator 10.
Further, it is noted that when the rail 56 is segmented, the rail assemblies
90 may be attached
to each other during the cleaning procedure. That is, to clean the tubes 24
closest to the
inspection opening 32, a single rail assembly 90 is coupled to a nozzle
assembly 58 and to the
water manifold 92. The rail 56 is then passed through the drive assembly 54
and the nozzle
assembly 58 is inserted into the steam generator 10 and the tubes 24 cleaned.
The water
manifold 92 does not pass through the drive assembly 54. Thus, once the tubes
24 closest to
the inspection opening 32 are cleaned, the water manifold 92 may be decoupled
from the first
rail assembly 90, a second rail assembly 90 may then be coupled to the first
rail assembly 90,
and the water manifold 92 is recoupled to the second rail assembly 90. The
rail 56 is now
longer and the rail body first end 74 may be moved further into the steam
generator 10. This
procedure may be repeated by adding additional rail assemblies 90 until the
rail 56 has a
sufficient length to extend across the steam generator 10.
[0077] Before, the cleaning operation occurs, however, it is desirable to
align the
nozzles 600 with the tube gaps 25. That is, as noted above, for the cleaning
spray to reach as
many tubes 24 as possible, it is desirable for the spray to be substantially
aligned with the
center of the tube gaps 25. Further, as different inspection openings 32 may
be spaced
differently from the adjacent tubes 24, the location of the tubes 24 must be
determined prior
to inserting the rail 56 with a nozzle assembly 58. Thus, as shown in Figure
15, the rail 56
may have an a positioning assembly 300 temporarily coupled thereto. The
positioning
assembly 300 includes a body 302, stop 304, an adjustable pointer assembly 306
and a
plurality of indicia 308 (Fig.4). The positioning assembly body 302 is
substantially similar in
dimensions to a rail assembly body 96, but does not include internal passages.
The
positioning assembly body 302 is coupled to the first end of the rail 56 and
becomes the rail
first end 74. The stop 304 is coupled to the positioning assembly body 302,
i.e. to the rail
18
CA 02777917 2016-06-02
WO 2011/078916
PCT/US2010/055207
first end 74. The stop 304 is sized so as to not pass between adjacent tubes
24. The
adjustable pointer assembly 306 is movably coupled to the drive assembly 54
adjacent the
rail 56 and is structured to move in a direction substantially parallel to the
longitudinal axis
of the rail 56. The plurality of indicia 308 are disposed on the rail 56. The
indicia 308 are,
preferably, lines, or line segments, extending across the rail body outer face
190. The indicia
308 are spaced as a multiple of the tube centerline distance, preferably the
multiple is one.
Further, the distance between the stop 304 and the indicia 308 is known and
structured so
that, when the stop contacts a tube 24, the indicia are a known distance from
the tube 24
centerline and/or the centerline of the tube gap 25.
[0078] In this configuration, the positioning assembly body 302 is inserted
into the
steam generator as described above, however, instead of passing between the
tubes 24, the
stop 304 will contact the tube 24 closest to the inspection opening 32. The
location of the
tube 24 closest to the inspection opening 32 can therefore be determined. Once
the location
of the tube 24 closest to the inspection opening 32 are known, the adjustable
pointer
assembly 306 is positioned to match one of the indicia 308. The adjustable
pointer assembly
306 is then temporarily fixed at that location. The rail 56 is then withdrawn
from the steam
generator 10 and the nozzle assembly 58 is attached to the rail 56. The rail
56 is reinserted
into the steam generator 10 and the rail 56 is moved until the adjustable
pointer assembly 306
again is aligned with an indicia 308. In this configuration, the nozzles 600
will be disposed
substantially at the tube gap 25 centerline. After a cleaning spray is
applied, the rail 56 may
then be indexed (moved) forward until the adjustable pointer assembly 306 is
aligned with
the next indicia 308 indicating that the nozzles 600 are now disposed at the
next tube gap 25.
This operation may be repeated until all tube gaps 25 have been cleaned. Where
the rail 56
includes a number of rail assemblies 90, the at least one indicia 308 includes
a plurality of
indicia 308 is disposed on each rail assembly 90.
[0079] The adjustable pointer assembly 306 includes at least one fastener 310
and an
elongated body 312 having an indicator 314 thereon. Further, the drive
assembly 54 includes at
least one fastener opening 313 adjacent the rail 56. The adjustable pointer
assembly body 312
has a longitudinal slot 316 therein, and has at least one fastener 310, each
disposed through one
adjustable pointer assembly body slot 316 and coupled to one fastener opening
313. Thus, the
adjustable pointer assembly body 312 is movably coupled to the drive assembly
54 and may be
moved longitudinally as well as temporarily fixed thereto.
19
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
[0080] The nozzle assembly 58 may include essentially fixed nozzles, but
preferably
includes movable nozzles 600 so as to increase the effective cleaning area to
which water
may be applied. Motion of the nozzles 600 is generated by an oscillator
assembly 330 (Fig.
I). The oscillator assembly 330 is structured to produce a cyclic motion and
is operatively
coupled to the drive shaft 72. Thus, the drive shaft 72 moves cyclically as
well. As shown in
Figure 8, the oscillator assembly 330 (Fig. 4) includes a housing assembly
332, a motor
assembly 334 (Fig. 1) having an elongated output shaft 336 and a gear assembly
338. The
oscillator assembly motor assembly 334 is coupled to the oscillator assembly
housing
assembly 332. The oscillator assembly motor assembly 334 may include a control
assembly
450 and a sensor assembly 452 having an encoder 454 and a mechanical
resistance sensor
456, all shown schematically and detailed below. The oscillator assembly motor
assembly
334 is structured to rotate the output shaft 336 in two directions. That is,
the oscillator
assembly motor assembly 334 may rotate the oscillator assembly motor output
shaft 336 in
two directions.
[0081] As noted above, the sludge lance 50 often must be operated in a tight
quarters. As such, while the longitudinal axis of oscillator assembly motor
assembly 334
and/or output shaft 336 could be aligned with the longitudinal axis of the
drive shaft 72, it is
preferable for the oscillator assembly 330 to extend about perpendicular to
the longitudinal
axis of the drive shaft 72, thereby reducing the overall length of the sludge
lance 50. Thus,
the oscillator assembly gear assembly 338 is, preferably, a miter gear
assembly. The
oscillator assembly gear assembly 338 has a first gear 340 a second gear 342,
and a miter
gear socket member 343. The oscillator assembly gear assembly first and second
gears 340,
342 are operatively coupled. The first gear 340 is fixed to the oscillator
assembly motor
output shaft 336. The second gear 342 is coupled to the miter gear socket
member 343 which
defines a keyed opening 344. That is, for each embodiment of the nozzle
assembly 58A,
58B, the oscillator assembly gear assembly 338 has a different miter gear
socket member
343. The miter gear socket member 343 has a tubular portion 350 and a
generally
perpendicular flange 352. The miter gear socket member tubular portion 350 is
disposed
within the central opening of the second miter gear 342. The miter gear socket
member
tubular portion 350 is hollow and defines a key socket. The miter gear socket
member flange
352 includes fastener openings 354 which are aligned with threaded bore holes
356 in the
second miter gear 342. It is noted that, rather than using the miter gear
socket member 343 so
as to make the assembly adaptable for use with both embodiments of the nozzle
assembly
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
58A, 58B, the second gear 342 may be formed with a specific opening (not
shown) for use
with only one nozzle assembly 58A, 58B. Accordingly, as used herein, the
"second gear
[with a] keyed opening" shall mean the second gear 342 with the associated
miter gear
socket member 343 or the equivalent structure of a second gear 342 having a
keyed opening.
[0082] The drive shaft second end 84 extends from the rail body 70 and, as
noted
above, the outer perimeter may be a keyed extension 134 or coupled to a key
134 for a keyed
opening. That is, in the first embodiment, the drive shaft second end 84 is a
key and in the
second embodiment the drive shaft second end 84 is threaded and passed through
a nut 570.
As used herein, the nut 570 is a movable part of the drive shaft second end 84
so this
configuration is the same as the drive shaft second end 84 being a key sized
to correspond to
the miter gear socket member keyed opening 344.
[0083] For either type of drive shaft keyed second end 346, the drive shaft 72
may
move through the second gear keyed opening 344. That is, if the drive shaft
second end 84 is
not threaded, the drive shaft second end 84, and more specifically the drive
shaft keyed
second end 346 may slide through the second gear keyed opening 344. If the
drive shaft
second end 84 is threaded, rotation of the threaded collar 570 causes the
drive shaft 72 to
move through the threaded collar 570, and the drive shaft 72 moves through the
second gear
keyed opening 344. Thus, the drive shaft keyed second end 346 is disposed in
the second
gear keyed opening 344 and the drive shaft 72 may move axially through the
second gear
342.
[0084] Both embodiments of the nozzle assembly 58A, 58B include an elongated
nozzle assembly body 400, 500. As noted above, there are preferably at least
two lateral
nozzles 600. The nozzles 600 are in fluid communication with the nozzle
assembly body
water passage 401 and the at least two lateral nozzles 600 are structured to
move relative to
the rail 56. That is, the nozzle assembly body 400, 500 is coupled to the
drive shaft 72 and
movement of the drive shaft 72 causes the nozzle body 400, 500 to move
relative to rail 56.
[0085] In one embodiment, the nozzle assembly 58A provides for rotating
nozzles
600. That is, as shown in Figure 6, the nozzle assembly body 400 is an
elongated,
substantially hollow, substantially linear tube 402 having a first end 404, a
medial portion
406 and a second end 408. The nozzle assembly body 400 defines the nozzle
assembly body
water passage 401. The nozzle assembly body 400 is structured to be rotatably
coupled to the
rail 56, or in the case of a segmented rail, to the head assembly 170, with
the nozzle assembly
body second end 408 and nozzle assembly body medial portion 406 disposed
within the rail
21
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
body 70 (or within the head assembly body 172) and the nozzle assembly body
first end 404
extending from the rail first end 74 (or extending from the head assembly body
first end 174).
[0086] In this embodiment, the nozzles 600 are generally perpendicular
extensions
403 from the nozzle assembly body 400. There are preferably six nozzles 600,
with three
nozzles 600 extending parallel to each other in a first direction, and three
other nozzles 600
extending in the opposite direction. The opposing nozzles 600 preferably share
a
substantially common axis. Further, the combined length of the opposing
perpendicular
extensions 403 have a greater width than the tube gap 25 through which the
rail 56 is
inserted. Thus, the longitudinal axis of the perpendicular extensions 403 must
be oriented in
a direction substantially parallel to the longitudinal axis of the tubes 25
during insertion, as
well as any subsequent longitudinal movement, of the rail 55. During cleaning,
nozzle
assembly body 400, and therefore the perpendicular extensions 403, are
rotated, up to about
180 degrees, so as to provide a greater cleaning area. That is, the oscillator
assembly motor
assembly 334 is structured to reciprocate the drive shaft 72 as follows. First
the oscillator
assembly motor assembly 334 moves the drive shaft 72 up to about ninety
degrees in a first
direction. The oscillator assembly motor assembly 334 then returns the drive
shaft 72 to its
original orientation. The oscillator assembly motor assembly 334 then moves
the drive shaft
72 up to about ninety degrees in a second, opposite direction. This means that
the
perpendicular extensions 403 may travel over about 180 degrees. During this
rotation, the
perpendicular extensions 403 rotate into the tube gaps 25 between the tubes
adjacent the rail
56. Further, the distal end of the nozzle assembly body 400 may include a
soft, e.g. non-
metallic, cap 409. This soft cap 409 protects the tubes 24 from damage if the
rail 56 is not
properly aligned with the tube gap 25 through which it is inserted. Further,
the cap 409
preferably has a width, or diameter, that is greater than the rail body 70.
Thus, the rail body
70 should be prevented from moving into a gap that is more narrow than the
rail body 70.
Further, the perpendicular extensions 403 may also include a non-metallic
sleeve 411. The
sleeve 411 helps protect the tubes 24 if the nozzle assembly body 400 is not
properly aligned
with the perpendicular extensions 403 disposed at the tube gaps 25.
[0087] For this embodiment, the longitudinal axis of the nozzle body 400 is
aligned
with the drive shaft 72. Thus, the nozzle body 400 is offset from the rail
body water passage
78 (or head assembly water passage 178) and would not be in fluid
communication therewith.
Accordingly, at the rail body first end 74 (or within the head assembly 170)
there is a first
end fluid passage 410 between rail body water passage 78 (or head assembly
water passage
22
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
178) and the rail body drive shaft passage 80 passage (or the head assembly
drive shaft
passage 180). Further, there is at least one fluid port 412 in the nozzle
assembly body medial
portion 406. The nozzle assembly at least one fluid port 412 is positioned at
said rail body
first end fluid passage 410. The at least one fluid port 412 is in fluid
communication with the
nozzle body water passage 401. Thus, the at least one fluid port 412 allows
for fluid
communication between the rail body water passage 78 (or head assembly water
passage
178) and the nozzle body water passage 401. Preferably, the edges of the at
least one fluid
port 412 are cut at an angle corresponding to the direction of the fluid flow
so as to reduce
turbulence.
[0088] In this configuration, the high pressure water is exposed to the drive
shaft
passage 80. To resist infiltration of water into the drive shaft passage 80, a
seal is provided.
More specifically, the nozzle assembly body medial portion 406 includes a
solid portion 414
disposed between the nozzle body water passage 401 and the nozzle assembly
body second
end keyed socket 420, discussed below. The nozzle assembly body 400 includes a
seal
assembly 416 having a plurality of seals 415. The plurality of seals 415 are
disposed about
the nozzle assembly body 400 and are structured to substantially resist water
escaping about
the nozzle assembly body 400. The seal assembly 416 including at least a first
seal 415A and
a second seal 415B. The first seal 415A is disposed immediately adjacent the
rail body first
end 74 and is structured to resist water passing through said rail body first
end 74. A bearing
may be disposed at this location as well. The second seal 415B disposed about
the nozzle
assembly body solid portion 414 and structured to resist water passing through
the drive shaft
passage 80. The second seal 415B may include radial channels (not shown)
structured to
communicate water laterally. This type of seal 415B requires an exhaust
passage 418 (Fig. 4)
in the head assembly body 172. In this configuration, the water being forced
down the drive
shaft passage 80 may exit the head assembly body 172.
[0089] Further, the nozzle body 400 is structured to rotate about the nozzle
body
longitudinal axis thereby providing a greater coverage area for the cleaning
spray.
Preferably, the nozzle assembly body second end 407 defines a keyed socket
420. Further,
as noted above, the drive shaft first end 82 is a key 134. The drive shaft
first end key 134
corresponds to the nozzle assembly body second end keyed socket 420. Thus,
when the
nozzle body 400 is partially disposed in the rail body 70 (or head assembly
body 170), the
drive shaft keyed first end 134 is temporarily fixed to the nozzle body second
end keyed
socket 420 whereby rotation of the drive shaft 72 causes the nozzle body 400
to rotate.
23
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
[0090] There is potentially a nozzle assembly body 400 alignment problem when
the
rail 56 is formed from rail assemblies 90. That is, as discussed above, a user
must know the
orientation of the nozzle body 400 within the steam generator 10 as the nozzle
body 400 may
only be moved when the perpendicular extensions 403 are substantially parallel
to the
longitudinal axis of the tubes 25. When the drive shaft 72 is segmented and
coupled by
keyed extensions 134 and sockets 136, however, there is the potential for
"play" in the
couplings. The couplings each have a tolerance and, when the tolerance is
multiplied by the
number of couplings, the effect of the combined tolerances may be too
significant. That is,
the combined tolerances may allow the perpendicular extensions 403 to be in
the tube gaps
25 when the drive shaft second end 84 is in its original orientation, i.e.
when the nozzle body
400 was properly aligned during insertion.
[0091] To address this problem, the keyed extensions 134 and sockets 136 are
tapered and the drive shaft 72 is biased toward the drive shaft first end 82.
A keyed extension
134 is shown in Figure 7A. It is understood that the keyed socket 136 has a
corresponding
shape. The keyed socket 136 is tapered, having its major (larger) cross-
sectional area
immediately adjacent the drive shaft segment 94 and the minor (smaller) cross-
sectional area
distal to the drive shaft segment 94. Further, as described below, the drive
shaft 72 is biased
toward the drive shaft first end 82 by a plunger 434 described below. This
bias
reduces/controls the "play" between the drive shaft segments 94. To ensure a
tight fit
between each keyed extension 134 and keyed socket 136, the keyed extension 134
may have
a taper that between about 0.0 degrees and 4.0 degrees, and more preferably
about 2.0
degrees sharper than the taper of the socket 136. As noted above, the drive
shaft 72 is
structured to slide through the oscillator assembly second gear keyed opening
344, as
described above, and it is desirable to bias the drive shaft 72 forward so as
to bias the keyed
extensions 134 into the keyed sockets 136. As shown in Figure 8, this is
accomplished by a
keyed socket insert assembly 430 on the oscillator assembly housing assembly
332. The
keyed socket insert assembly 430 is structured to engage the drive shaft 72
and bias the drive
shaft 72 toward the rail body first end 74. The keyed socket insert assembly
430 includes a
generally tubular, keyed body 432, a plunger 434, a biasing device 436, and a
cap 438. The
keyed socket insert assembly body 432 outer radial surface is shaped to
correspond to the
second gear keyed opening 344. The keyed socket insert assembly body 432
further has an
elongated keyed passage 440. The keyed socket insert assembly body keyed
passage 440 is
structured to correspond to the drive shaft keyed second end 84. The keyed
socket insert
24
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
assembly plunger 434 is disposed in the keyed socket insert assembly body
elongated passage
440. The keyed socket insert assembly cap 438 is coupled to the keyed socket
insert
assembly body 432 at the back end of the keyed socket insert assembly body
elongated
passage 440. The keyed socket insert assembly biasing device 436, which is
preferably a
compression spring 437, is disposed between the keyed socket insert assembly
plunger 434
and the keyed socket insert assembly cap 438 and is structured to bias the
keyed socket insert
assembly plunger 434 toward rail body first end 74. Thus, the keyed socket
insert assembly
plunger 434 engages the drive shaft 72 thereby biasing the drive shaft 72
toward the rail body
first end 74.
[0092] As noted above, the perpendicular extensions 403 must be oriented in a
direction substantially parallel to the longitudinal axis of the tubes 25
during insertion, as
well as any subsequent longitudinal movement, of the rail 56. Generally, the
orientation of
the perpendicular extensions 403 is monitored by the oscillator assembly motor
control
assembly 450 (shown schematically in Fig. 1). That is, the oscillator assembly
motor control
assembly 450 is structured to receive input, typically an electronic signal
carrying data, from
the sensor assembly 452. The sensor assembly 452 (shown schematically in Fig.
1) includes
an encoder 454 (shown schematically in Fig. 1)structured to track the
orientation of the drive
shaft 72 as well as a mechanical resistance sensor 456 (shown schematically in
Fig. 1). The
resistance sensor 456 is, typically, a current sensor that detects the amount
of current being
used by the oscillator assembly motor assembly 334. Both the encoder 454 and
the
mechanical resistance sensor 456 generate the input received by the oscillator
assembly
motor control assembly 450. That is, oscillator assembly motor assembly 334 is
actuated in
response to input, e.g. input from an operator, and to receive input from the
encoder 454 and
the resistance sensor 456. The encoder 454 is structured to track the position
of the gears in
the oscillator assembly gear assembly 338 and to provide position data to the
oscillator
assembly motor control assembly 450. As the oscillator assembly gear assembly
338 is in a
fixed orientation relative to the drive shaft 72, the orientation of the drive
shaft 72 is known
as well. It is noted that the encoder 454 is reset each time the rail 56 is
inserted into the steam
generator after the rail body 70 has been positioned in the proper
orientation. As the
oscillator assembly motor control assembly 450 is electronic, a loss of power
could cause the
system to lose track of the orientation of the perpendicular extensions 403.
This is not
desirable as longitudinal movement of the rail 56 with the perpendicular
extensions 403 in
any orientation other than substantially aligned with the longitudinal axis of
the tubes 24
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
could result in damage to the tubes 24. Accordingly, a nozzle orientation
reset device 460 is
included with the oscillator assembly 330.
[0093] The nozzle orientation reset device 460 is structured to position the
nozzle
assembly body 400, and therefore the perpendicular extensions 403 with the
nozzles 600, in a
selected orientation, typically vertically. The nozzle orientation reset
device 460 includes an
end plate 462 and a lug 464, as shown in Figure 16. The end plate 462 is
disposed adjacent to
keyed socket insert assembly body 432. That is, the end plate 462 is disposed
in a plane that
is generally perpendicular to the axis of rotation of the drive shaft 72
adjacent the keyed
socket insert assembly body 432 (Fig. 6). The end plate 462 has an arcuate
channel 466
thereon. The end plate arcuate channel 466 has a center that is substantially
aligned with the
axis of rotation of the drive shaft 72. The lug 464 is disposed on the keyed
socket insert
assembly body 432 and extends axially therefrom. The lug 464 is sized and
positioned to be
movably disposed in the arcuate channel 466. Thus, as the oscillator assembly
motor
assembly 334 is actuated, the lug 464 reciprocates in the channel 466. The
arcuate channel
466 extends over 180 degrees and, when the perpendicular extensions 403 are
substantially
aligned with the longitudinal axis of the tubes 24, the lug 464 is
substantially centered in the
channel 466.
[0094] The orientation of the nozzle assembly body 400 is reset, i.e. the
oscillator
assembly motor 450 is reset, by moving the lug 464 in the channel 466 until
the lug 464
contacts one end of the channel 466. The oscillator assembly motor control
assembly 450 is,
preferably, programmed with data indicating the angular distance between the
end of the
channel 466 and the neutral position. When contact is made, the resistance
sensor 456
provides position input data to the oscillator assembly motor control assembly
450 and the
oscillator assembly motor control assembly 450 utilizes the encoder position
data to
reposition nozzles, i.e. the perpendicular extensions 403, in a selected, i.e.
the neutral,
orientation.
[0095] In a second embodiment, shown in Figure 17, the nozzle assembly 58B is
structured to move the nozzles 600 vertically. That is, in the second
embodiment the nozzle
assembly 58B includes an elongated body assembly 500 having an elongated first
end 502, a
medial portion 504, and an elongated second end 506. The nozzle assembly body
assembly
medial portion 504 is arcuate, preferably extending over an arc of about
ninety degrees,
whereby the nozzle assembly body assembly first end 502 and the nozzle
assembly body
assembly second end 506 are disposed at about a right angle relative to each
other. The
26
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
nozzles 600 are disposed at the nozzle assembly body assembly first end 502.
The nozzles
600 are structured to move vertically due to the nozzle assembly body assembly
first end 502
being structured to collapse. That is, the nozzle assembly body assembly first
end 502 is
structured to move between a first position, wherein the nozzle assembly body
assembly first
end 502 is extended, and a second position wherein the nozzle assembly body
assembly first
end 502 is retracted. Preferably, in use, the nozzle assembly body assembly
second end 506
extends generally horizontally from the rail 56 and the nozzle assembly body
assembly
medial portion 504 curves downwardly. In this configuration, when the nozzle
assembly
body assembly first end 502 is in the first position, the nozzles 600 are at a
lower elevation
than when the nozzle assembly body assembly first end 502 is in the second
position.
[0096] The nozzle assembly body assembly first end 502 may be structured to
collapse via a bellows device but, in the preferred embodiment, movement of
the nozzles 600
is accomplished by a retraction assembly 520 (Fig. 18). That is, the nozzle
assembly body
assembly 500 includes a body member 510 and the retraction assembly 520. The
nozzle
assembly body assembly body member 510 is a substantially rigid member having
an
elongated first end 512, a medial portion 514, and an elongated second end
516. The nozzle
assembly body assembly body member medial portion 514 is arcuate, preferably
extending
over an arc of about ninety degrees, whereby the nozzle assembly body assembly
body
member first end 512 and the nozzle assembly body assembly body member second
end 516
are disposed at about a right angle relative to each other. The retraction
assembly 520
includes a cable 522 and a sliding head assembly 524. As shown in Figures 18
and 19, the
sliding head assembly 524 is movably coupled to the nozzle assembly body
assembly body
member first end 512 and is structured to move longitudinally relative
thereto. The retraction
assembly cable 522 is movably disposed in the nozzle assembly body assembly
body member
510 and is coupled to the sliding head assembly 524. In this configuration,
movement of the
retraction assembly cable 522 moves the sliding head assembly 524. The nozzles
600 are
disposed on the sliding head assembly 524. Thus, movement of the sliding head
assembly
524 relative to the nozzle assembly body assembly body member first end 512
is, generally,
over a vertical axis.
[0097] The nozzle assembly body assembly body member 510 defines a number of
passages. For example, in this embodiment, the nozzle assembly water passage
401 is
divided into a first elongated high pressure channel 530 and a second
elongated high pressure
water channel 532. The first and second high pressure channels 530, 532 are
disposed in the
27
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
substantially the same plane and extend substantially parallel to each other.
One or both of
the high pressure channels 530, 532 may include a passage in fluid
communication with the
sliding head assembly body 544. In this configuration, the water pressure acts
to bias the
sliding head assembly body 544 into the first position, discussed below.
Further, at the
nozzle assembly body assembly body member first end 512 there are, preferably,
two bores
536 structured to support a pair of guide shafts 540, 542.
[0098] That is, at the nozzle assembly body assembly body member first end 512
there are a pair of guide shafts, i.e. first and second guide shafts 540, 542,
that extend
outwardly therefrom and generally parallel to the nozzle assembly body
assembly body
member first end 512 longitudinal axis. The first and second guide shafts 540,
542 interact
with the sliding head assembly 524. The sliding head assembly 524 further
includes a body
544. The sliding head assembly body 544 is movably coupled to the sliding head
assembly
first and second elongated guide shafts 540, 542 and is structured to move
between a first
extended position, wherein the sliding head assembly body 544 is spaced from
the nozzle
assembly body assembly body member first end 512, and a second position,
wherein the
sliding head assembly body 544 is disposed closer to the nozzle assembly body
assembly
body member first end 512. Preferably, the sliding head assembly body 544
defines two
passages 546 sized to correspond to the first and second guide shafts 540,
542. Thus, the
sliding head assembly body 544 can be slidably coupled to the first and second
guide shafts
540, 542. Further, the retraction assembly cable 522 is coupled to the sliding
head assembly
body 544. Thus, actuation of the cable 522 moves the sliding head assembly
body 544 over
the first and second guide shafts 540, 542 and relative to the nozzle assembly
body assembly
body member first end 512.
[0099] The sliding head assembly body 544 further defines two water passages
546.
The sliding head assembly body water passages 546 terminate in generally
lateral nozzles
600, as shown in Figure 18A. The nozzles 600 may open in the same direction,
but could
open in opposing directions or both lateral directions. The sliding head
assembly 524
further includes a first elongated high pressure tube 550 and a second
elongated high
pressure water tube 552. The first and second high pressure tubes 550, 552 are
coupled to
said sliding head assembly body 544. The first and second high pressure
channels 530, 532
are sized to accommodate the first and second high pressure tubes 550, 552.
Further, each of
the first and second high pressure tubes 550, 552 are coupled to, and in fluid
communication
with, one of the high pressure channel 530, 532 and one of the sliding head
assembly body
28
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
water passages 546. There are seals 554 disposed about the first and second
high pressure
tubes 550, 552 and are located between the first and second high pressure
tubes 550, 552 and
the first and second high pressure channels 530, 532. In this configuration,
as the sliding
head assembly body 544 moves between the first and second positions, the first
and second
high pressure tubes 550, 552 move in and out of the first and second high
pressure channels
530, 532. Finally, it is noted that the sliding head assembly body 544 may be
protected by a
shell 556 that is disposed about the sliding head assembly body 544 and
coupled to the nozzle
assembly body assembly body member second end 516. The sliding head assembly
body
shell 556 has slots 558 (Fig. 17) therethrough that are aligned with, and
extend over the path
of travel of the nozzles 600.
[00100] It is noted that because the nozzle assembly 58B does not rotate as
does the
embodiment having nozzle assembly 58A; the motion of the drive shaft 72 must
be a
longitudinal motion. That is, in this embodiment, the drive shaft 72 is
structured to move
longitudinally within the rail 56 between a first position, wherein the drive
shaft 72 extends
from the rail body first end 74, and a second position, wherein the drive
shaft 72 is shifted
towards the rail body second end 76. Further, the drive shaft first end 82 is
threaded coupling
or another type of temporarily fixable coupling. The cable 522 has a first end
526 and a
second end 528. The cable second end 528 is structured to be temporarily fixed
to the drive
shaft first end 82. The drive shaft first end 82 is temporarily coupled to the
cable second end
528. Thus, the longitudinal movement of the drive shaft 72 causes the cable
522 to move
longitudinally in the nozzle assembly body assembly body member 510.
[00101] The longitudinal motion of the drive shaft 72 is created by the
oscillator
assembly 330. The majority of the oscillator assembly 330 components are the
same as
above and like reference numbers will be used herein below. That is, the motor
assembly 334
and the gear assembly 338 are substantially the same as described above. The
notable
difference between the prior embodiment and this embodiment is the connection
with the
drive shaft 72. In the prior embodiment, the drive shaft 72 is needed to
rotate so as to rotate
the nozzle assembly 58A. In this embodiment, the drive shaft 72 must be moved
longitudinally. This is accomplished by having a threaded portion 576 on the
drive shaft
second end 84 and having a nut, or threaded collar 570, as described above,
disposed between
the drive shaft second end 84 and the oscillator assembly gear assembly 338.
[00102] That is, in this embodiment the drive shaft second end 84 includes a
threaded
collar 570. The threaded collar 570 has a keyed outer radial surface 572,
preferably a square
29
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
shape, and a threaded inner surface 574. The threaded collar outer radial
surface 572 is
shaped to correspond to the second gear keyed opening 344. The drive shaft
second end 84
also has a threaded portion 576. The drive shaft second end threaded portion
576 extends
beyond the rail body second end 76 so that it is exposed. The threaded collar
570 is disposed
within the second gear keyed opening 344. In this configuration, actuation of
the oscillator
assembly motor assembly 334 causes the threaded collar 570 to rotate. Thus, as
the drive
shaft second end threaded portion 576 is disposed in, and engaging, the
threaded collar
threaded inner surface 574, the rotation of the threaded collar 570 causes the
drive shaft
second end threaded portion 576 to translate through the threaded collar 570.
This creates the
longitudinal movement in the drive shaft 72.
[00103] For this configuration to operate, and not unscrew the drive shaft
segments
94 from each other, the drive shaft 72 must not rotate. Further, there is
still a need to know
the configuration, and/or position, of the nozzle assembly body 500 in the
event of a loss of
power. That is, as noted above, the oscillator assembly motor assembly 334
includes an
electronic oscillator assembly motor control assembly 450 that is structured
to track the
location of the nozzle assembly 58. As the oscillator assembly motor control
assembly 450 is
electric, a loss of power may cause the oscillator assembly motor control
assembly 450 to
lose data relating to the position of the nozzle assembly 58B. In this
embodiment, both of
these functions are accomplished by the oscillator assembly nozzle position
reset device 580.
[00104] The nozzle position reset device 580 includes a drive shaft extension
582, a
movable indicia 584, a fixed indicia 586 and a keyed opening 588. The drive
shaft extension
582 extends longitudinally from the drive shaft second end 84. The drive shaft
extension 582
is keyed and may be an elongated portion of the drive shaft second end 82 that
extends
beyond the drive shaft second end threaded portion 576. The movable indicia
584 is disposed
on the drive shaft second end 84 and, more preferably, on the said drive shaft
extension 582.
The fixed indicia 586 is disposed adjacent to the drive shaft extension 582,
and may simply
be the outer surface of the oscillator assembly housing assembly 332.
Preferably, when the
sliding head assembly body 544 is in the first position, the two nozzle
position reset device
indicia 584, 586 are aligned. As the drive shaft 72 is moved longitudinally
toward the rail
body second end 76, thereby moving the cable 522 and the sliding head assembly
body 544,
the two nozzle position reset device indicia 584, 586 become spaced from each
other. To
reset the position of the sliding head assembly body 544, the two nozzle
position reset device
indicia 584, 586 must be realigned. That is, the oscillator assembly motor
assembly 334 is
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
actuated in the direction required to return the two nozzle position reset
device indicia 584,
586 into alignment. Thus, comparing the location of the movable indicia 584 to
the fixed
indicia 586 indicates the position of the drive shaft 72 relative to the rail
body 70. In a
preferred embodiment, the oscillator assembly housing assembly 332 includes an
offset end
plate 590 that is spaced from the threaded collar 570 in an axial direction.
The offset end
plate 590 has the keyed opening 588 therethrough. The offset end plate opening
588 is sized
to allow the drive shaft extension 582 to pass therethrough. The fixed indicia
584 is disposed
on the offset end plate 590. Moreover, the keyed drive shaft extension 582
passing through
the keyed opening 588 prevents the drive shaft 72 from rotating. Thus, as the
threaded collar
570 rotates, the orientation of the drive shaft 72 is maintained and the
interaction with the
threaded collar 570 causes the drive shaft 72 to translate longitudinally.
[00105] In both nozzle assembly embodiments 58A, 58B, the water flow must be
turned about ninety degrees from the direction the water travels in the nozzle
assembly body
400, 500, to the lateral direction that the nozzles 600 face, as shown in
Figure 21. This
change in direction, especially if it is close to the nozzles 600, may create
a turbulent flow
resulting in an irregular spray pattern emerging from the nozzles 600. To
return the water
flow to a generally laminar flow, at least one flow straightener 602 is
disposed in at least one
nozzle 600. As shown in Figure 22, the flow straightener 602 includes a body
604 having a
plurality of passages 606 therethrough. The flow straightener passages 606
extend
substantially parallel to each other. The at least one flow straightener body
604 is, preferably,
a generally circular disk with the flow straightener passages 606 extending in
an axial
direction. Preferably, the flow straightener 602 is disposed in at least one
said lateral nozzle
600, as opposed to a location upstream in the nozzle assembly body 400, 500.
Preferably,
each flow straightener body 604 is between about 0.1 and 0.2 inch in diameter,
and more
preferably about 0.15 inch in diameter. There are preferably between about ten
and thirty
flow straightener passages 606, and more preferably about nineteen flow
straightener
passages 606. The flow straightener passages 606 are between about 0.01 and
0.03 inch in
diameter, and more preferably about 0.02 inch in diameter.
[00106] The mounting assembly 52 is structured to be coupled to the steam
generator
and to be adjustable so that the sludge lance 50, and more specifically the
rail 56 may be
aligned with a tube gap 25. Preferably, as shown in Figures 23-25, the
mounting assembly 52
includes a "L" shaped mounting bracket 700 having a vertical, first plate 701,
a horizontal,
second plate 702, as well as a floating third plate 704, and a fastener
assembly 706. The first
31
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
plate 701 is structured to be coupled to the inspection opening 32. That is,
the inspection
opening 32 includes fastener holes used to secure a cover (not shown) to the
inspection
opening 32. The fastener assembly 706 includes fasteners 708 structured to
pass through
openings (not shown) in the first plate 701 and into the inspection opening 32
fastener holes.
The second plate 702 is fixed to the first plate 701 at about a right angle.
That is, the second
plate 702 extends generally horizontally. The third plate 704 is movably
coupled to the
second plate 702. The fastener assembly 706 is structured to temporarily fix
the third plate
704 to the second plate 702.
[00107] That is, the third plate 704 is structured to be adjustable relative
to the
inspection opening 32 and the second plate 702. For example, the second plate
702 includes
two laterally extending slots 710 (Fig. 25). The third plate 704 include a
first threaded
opening 712 and second threaded opening 714 (Fig. 24). The first threaded
opening 712 and
the second threaded opening 714 are each structured to align with one of the
second plate
laterally extending slots 710 when the third plate 704 is disposed on top of
the second plate
702. The fastener assembly 706 includes two threaded knobs 720. Each threaded
knob 720
is structured to extend upwardly through one of the second plate laterally
extending slots 710
and to be threaded into one of the third plate threaded openings 712, 714. In
this
configuration, the third plate 704 may be moved laterally relative to the
second plate 702 and,
when a proper position is reached, the threaded knobs 720 may be tightened
thereby
temporarily fixing the third plate 704 to the second plate 702.
[00108] Further, the angle of the rail's longitudinal axis relative to the
inspection
opening 32 may be adjusted. That is, the third plate 704 includes a drive
assembly coupling
730. The drive assembly coupling 730 is structured to allow the drive assembly
54 to be
rotated relative to the third plate 704. That is, the second plate 702
includes an arcuate slot
732 disposed on the longitudinal axis of the second plate 702. The third plate
704 has an
upwardly extending lug 734 disposed on the longitudinal axis of the second
plate 702. The
third plate 704 also has an arcuate slot 735 disposed on the longitudinal axis
of the third plate
704. The fastener assembly 706 includes a third threaded knob 720. The drive
assembly 54
has two mounting openings, a first mounting opening 736, (Fig. 14)
corresponding to the
mounting assembly lug 734, and a threaded, second mounting opening 738 (Fig.
14),
corresponding to the threaded knob 720. The second mounting opening 738 is
structured to
align with the second plate arcuate slot 732 when the third plate 704 is
disposed on the
second plate 702. When assembled, the drive assembly 54 is disposed on the
third plate 704
32
CA 02777917 2012-04-17
WO 2011/078916
PCT/US2010/055207
with the mounting assembly lug 734 disposed in the first mounting opening 736
and the
threaded knob 720 disposed in, i.e. engaging, the threaded, second mounting
opening 738. In
this configuration, the drive assembly 54 may be rotated about the mounting
assembly lug
734 until the desired angle is achieved. When the drive assembly 54 is
aligned, the threaded
knob 720 is passed through the second plate arcuate slot 732 and the third
plate arcuate slot
735 and into the second mounting opening 738. To temporarily fix the drive
assembly 54 to
the third plate 704, the threaded knob 720 is tightened.
1001091 The second plate 702 and the third plate 704 may each have a set of
indicia
740, 742 thereon. The mounting assembly indicia 740, 742 are, preferably,
scales or a similar
marking. The position of the mounting assembly indicia 740, 742 relative to
each other may
be recorded when the sludge lance 50 is successfully used (meaning the rail 56
is properly
aligned with the tube gap 25). Thereafter, the second plate 702 and the third
plate 704 may
be pre-positioned relative to each other according to the recorded positioning
the next time
the sludge lance 50 is used at that inspection opening 32.
[00110] While specific embodiments of the invention have been described in
detail, it
will be appreciated by those skilled in the art that various modifications and
alternatives to
those details could be developed in light of the overall teachings of the
disclosure.
Accordingly, the particular embodiments disclosed are meant to be illustrative
only and not
limiting as to the scope of the invention, which is to be given the full
breadth of the appended
claims and any and all equivalents thereof.
33
