Note: Descriptions are shown in the official language in which they were submitted.
106006Z
The present invention concerns a water/steam
coupling for a roll in a paper or cardboard calender by
mediation of which the fluid heating the calender roll is
conducted from a stationary steam supply conduit into the
calender roll, and which coupling comprises sealing elements
between the stationary and the rotating part.
As is known, the calendering event is also influenced
by the temperature of the calender rolls. High temperature
is beneficial in view of smoothness of the web. The calender-
ing process has in fact been likened to the ironing of fabric
with a flat iron, wherein pressure, temperature, moisture and
slidlng are effective factors. Thexefore frequently at least
part of the calender rolls are equipped with steam heating.
The object of the invention is, accordingiy, to provide a
water/steam coupling by the aid of which from a steam pipe
heating steam is conducted into the shell of a calender roll
and, correspondingly, the steam is removed therefrom.
Water/steam couplings known in prior art present a
heavy structure and the sole possibility existing for
supporting them has been a mediation of the calender roll's ;
bearing housing. It is however a fact that owing to the
bouncing of the calender rolls the calender rolls rise in
vertical direction, but during such movement the calender
rolls do not move retaining their horizontal alignment, but
rather one of their ends is moving ahead. For this and other
reason$ between the water/steam coupling and the roll an
elastic connection has to be provided so that it is able to
yield properly in such manner that the carbon gaskets or
equivalent of said coupling will not suffer breakage or become
displaced. In addition, changes of temperature cause in the
~- springs and on the sealing faces of the coupling various
forces, which impede the sealing.
., ~
-- 1 --
.
: , . . . .
-,
~0~iO06Z
The object of the present invention is accordingly
to avoid the drawbacks mentioned and to provide a simple
water/steam coupling for a calender roll and one which is
reliable in service. In order to achieve this and other
aims which will be apparent later, the invention is mainly
characterized in that the coupling comprises at least one
tubular shaft coaxial with the calender roll and which is
at one end connected to rotate along with the calender roll
by means of a bellows or equivalent compensating at least
for the angular misalignments, and that upon the outer said
. ..~, . ..
tubular shaft there is/are a sliding sleeve or sleeves
displaceable with respect to it in axial direction and rotating
along with it, in connection with which there are sealing
surfaces having a radial extension and wherein one of the two
mating surfaces consists of carbon rings or equivalent sealing
rings.
In the following the invention is described in
detail with reference to certain embodiments of the invention
presented in the figures of the attached drawing, but to which
the invention shall not be narrowly confined in any way. ~ -~
FIGURE 1 presents a single-acting water/steam
coupling in axial and central sectional view.
FIGURE 2 presents in like manner as Figure 1, a
I double-acting steam coupling.
FIGURE 3 shows a unit in which couplings according
to the invention are applied (a calender stack).
In view of describing the object of the application
of the water/steam co-pling of the invention, reference is
first made to Figure 3, according to which the calender
stack depicted therein consists of calender rolls 22 stacked
upon each other. The calender rolls 22 have been journalled
~y means of brackets 23~in the frame of the calender by
,
1a~60062
mediation of pivot axles 26. On the side opposite to the
pivot axles 26, lifting means 27 known in themselves in
prior art have been provided.
Steam is conducted into the calender rolls 22 to
serve the purposes already mentioned. This conduction of
steam is from the steam pipe 29 by valves 25 and the steam
couplings 100 of the invention. In Figure 3, a single-acting
steam coupling is indicated by the reference numeral 100a
and a double-acting steam coupling by 100b. The steam inlet
10 tubes leading to the steam coupling 100a and 100b carry the
reference numeral 24a. The draining tube of a double-acting
steam coupling 100b is identified as 24b. A single-acting
steam coupling is in this instance understood to mean that
the steam input is at one end of the calender roll 22 and
its removal at the opposite end of the roll, while a double-
acting coupling is understood to imply an arrangement in which
both the steam input and the steam removal take place at one
and the same end of the roll, provided by means of one single
coupling .
Referring now to Figures 1 and 2, in the following
two different embodiments of the steam coupling of the
- invention shall be described. In Figures 1 and 2 the calender
roll has the reference numeral 22 and the bearing housing of
the roll, the reference numeral 23. The roll 22 has been
fitted in a manner known in itself in prior art, with a
spherical bearing. The calender frame is schematically
indicated in Figures 1 and 2 by the reference numeral 21.
The steam couplings 100 shown in Figures 1 and 2
are substantially symmetrical with reference to their
30 central axis A-A. The steam entry is illustrated in the
Figures by a-rows B and the steam removal of the double-
acting steam coupling 100b in Figure 2, by arrows C~ As
.
~ 3 ~
.
. , . . . .- . - - . . ,. . . : . .
., .. :,. . : . .
106006Z
shown in Figure 1, the steam coupling comprises a central
tubular shaft 20, connected by its end adjacent to the
calender roll 22 by means of a comparatively stiff and
pressure-resistant bellows 15 to be contiguous with the
shell of the calender roll 22. As shown in Figure 2, the
equivalent structure consists of a tubular shaft 9 and of
a tube 14 residing therein and coaxial with it, both being
connected by bellows to be contiguous with the shell of
the calender roll 22. The tubular shaft 9 has been connected
by a bellows 15 to be contiguous with the end of the calender
roll and the tube 14 has been connected by a bellows 16 to
the steam draining tube 30 within the calender roll 22.
As shown in Figures 1 and 2, upon the tubular 9,
respectively 20, with the aid of keys 13 sliding sleeves 4
have been mounted, of which according to Figure 1 there is
only one, while Figure 2 shows two such sleeves opposing each
other. The sliding sleeves 4 have on their projecting part
sealing surfaces S with radial extension which have been
indicated by a heavy line in the figure. On one side of
these sealing surfaces there is a carbon ring 2 and on the
other side a carbon ring 5, these rings being non-rotating,
whereas the sliding sleeves 4 opposing them are connected to
rotate along with the tubular shaft 9, 20. To the purpose of
sealing~ furthermore O-rings 10 and 11 have been provided
between the various parts. As shown 1n Figure 1, the coupling
comprises a second carbon ring 19, which abuts on the cover
18 of the coupling. Between the carbon rings 5 of Figure 2
~nd between the carbon rings 5 and 19 of Figure 1 a spring 8
; has been fitted, which produces requisite sealing pressure
at the sealing surfaces S with radial extension.
- . .
:
-- 4
., :
, . , -. : . ., , . . , . : .
. - ,, -, . .. . -
~)60062
As shown in Figures 1 and 2, the couplings comprise
a body component 3, to which according to Figure 1 the end
flanges 12 and 18 have been affixed, and according to Figure
2 the end flanges 1 and 12. The said tubular coupling body
3 has been affixed to the supporting component 6, by
mediation of which the coupling body is integrally connected
to the bearing housing 23 of the roll 22. The figures
furthermore show a coupling housing 17, within which the
bellows 15, 16 have been accommodated.
The construction just described offers, among
other things, the additional advantage that the movement of
the sealing bodies with reference to each other, caused by
thermal expansion and by wear, has been concentrated at one
single surface: between the components 4 and 9.
As further regards the operation of the water/steam
coupling just described, the bellows 15, 16 are comparatively
rigid and their purpose is to co~pensate for angular misalign-
ment only, not for axial movements.
The invention is in no way confined to the embodiments
described here by way of an example only. The invention may
also be implemented e.g. so that the inner part of the coupling
is arranged to be non-rotating and the outer housing part, to
rotate along with the calender roll.
Hereinbelow follow the claims, and various details
of the invention may ~ary within the scope of the inventive
idea define~ by these claims.
~ .
: . ~: . ., ' . . . .
