Note: Descriptions are shown in the official language in which they were submitted.
~J ij ~3 c~ 3 -.
E~BR-[C~TION OF PRESSIJRE V:ESS~LS
B~CKGROUND OF Tl-lE :LNVENTION
The present invention relates generally to an improved
apparatus for the Eormatlon and procluct:ion o~ cylinclrical pressure
vessels or t:anks through metal spinnincJ operations, and more
part:icular:ly t:o -In apparatus arranged Eor the productioll of clouble-
ended vessels throuyh the simultaneou~ formation and~or areat:lon oE
encl closures along a hollow, thin-walled cylindrical work tube
rotatably supported within the apparatus. The apparatus oE the
present invention is designed to provide and facilitate the rapid
production of cdoub]e-ended pressure vesse:Ls whereby the
distribution of the wall thickness of the end cap por-tion of tlle
vessel may be controlled so as to provide a predetermined properly
distributed wall thickness which provides zones of increased
thickness where desired for durability and improved pressure vessel
or tank lifetime or performance.
In the past, pressure vessels or tanks, particularly thin-
walled tanks, have been typically fabricated from a central tubular
cylindrical body portion to which appropriately designed end caps
are secured, typically through welding operations. Such vessels
have, of course, been recoynized as being suited for a wide variety
of fluid re-tention applications. Because of the requirement o~
welding end caps to the cylindrical tube portion, the cost o~ labor
ancl material~s in the production of pressure vessels has been a
5 significant factor in their overall cost of production.
SUMMARY OF THE INVENTION
In accordance with the present invention, an apparatus and
process is provided which enables the production of double-ended
vessels through the simultaneous formation of end closures along a
cylindrical work tube, particularly thin-walled tubing. These end
~ 3~
closures may also be formed along the pat-tern ancl/or desicJn of the
commollly acceptecl and recognized tanlcs or ve~;sels. For e~mpLe,
-the apparatus oE the prasen-t invention is capable of producLny tank
ends which are consis-tent with thc ASME desiyns Eor hiCJII crown,
elliptical, ancl standarcl code ends, as well as non-code standar~
encls. 'rlle dlstr:Lh-ltion oE wall-thickness of the tan]c encls produced
by the apparatus of the present invent:Lon may be inEluenced 50 as
to provide yreater thickness at the knuckle area (the zone of
smallest radius of curvature) so as to create a vessel witll yreater
lo durability and extended lifetime. For example, it is recognized
that the lcnuckle zone adjacent the end of a pressure vessel is
typically the wea]cest point. In accordance with the apparatus of
the presen-t invention, however, a tank end may be formed through a
spinning technique wherein the wall thickness in the knuckle zone
is made greater than the wall thickness along the remaining
portions of the tank. By providing this greater thickness in the
tank at and along this area, the overall features such as streng-th,
reliability, and safety of the tank are improved.
As indicated, the apparatus of the present invention renders
it possible to fabricate a pressure vessel or tank by a spinn:Lng
technique wherein the opposed closed ends are simultaneously
formed. The availability of such simultaneous treatment
significantly reduces the time requlred ~or tank fabrication,
inasmuch as only one heating-and~cooling cycle is required for the
entire end cap fabrication operation. Additionally, the handling
normally required is significantly reduced because of the
simultaneous end cap Pormation capability.
Therefore, it is a primary object of the present invention to
provide an improved apparatus for khe formation of tank ends
through a metal spinning process wherein the tanks may be
-- 2
fabricated on an expedited and efficient basis, w:Lth the resultant
product havincJ improved mechallical properti.es,~ aludLrlg durabilLty
alld strength.
I~ ls ye-t: a ~urther ob;eat of the present invention to provide
an appara-tus for the production oE double-ended pressure vessels or
tanks where:Ln opposed tank ends are s.lmultaneously formed throuyh
a metal spinnirlcJ opera~ion.
Thus, in accordance with the present invantion, an apparatus
is provided which enables the formation and/or production of tank
ends through the simultaneous spinning ~ormation o~ such ends, and
wherein the spinniny operation utilizes forming rollers at opposed
ends which utilize forces which may vary during an axially
outwardly radially inwardly directed forming stro]ce as contrasted
with an axially inwardly radially outwardly directed forming
stroke. sy controlling the path and rate of motion of the forming
rollers, and thus the application of forces in this fashion, it is
possible to control the distribution of the wall thickness of the
tank end as well as the profile thereof, and accordingly provide
greater wall thickness in tha knuckle zone of the vessel, this area
normally comprising the weakest point of the tank and/or vessel.
It is yet a further object of the present invention to provide
an improved apparatus for the production of double-ended pressure
vessels or tanks through the simultaneous formation of identically
shaped or non-identically shaped end closures utiliziny metal
spinning techniques, and wherein the forming rollers employed in
the spinning operation are designed to move through successive
strokes or motion along one or more axes, and wherein the arcuate
spaciny for each of the individual strokes is controlled so as to
appropriately form a tailored wall thickness profile which provides
a tank end with added thickness at the knuckle portion thereof.
~ .3~r3l(l
Other and further objects of the present invention will hecome
apparent to those slcilled in the art ~IpOIl a study of thQ fo:l:LowlllcJ
specification, appenclecl clal.ms, and accompanylng drawincJE;.
IN T~IE DRAWIMGS
Fiyure 1 is a sicle elevatlonal view oE the apparatus o~ the
present;illvelltlon, and .illustratincJ a cylindrical work tube mounted
within the apparatus;
Figure 2 is an end view oE the apparatus illustrated in Figure
1, and illustrating, partially in phan-tom, the disposikion of the
support rollers during the end closure Eorming operation;
Fiyure 3 is a sectional view o~ typical tank end pro~iles, alld
illustra-ting the configurations thereoE;
Figure 4 is a schematic view of various positions occupied by
forming rollers during the operations of the apparatus of the
present invention, and further illustrating the typical arcuate
paths followed during individual passes followed and/or undertaken
by the forminy rollers;
Figure 5 is a side elevationaLl view o~ a portion o~ the
apparatus of the present invention, and illustra-ting a fragmentary
portion of a cylindrical work tube retained therewithin, with
Figure 5 further illustrating details o~ the clamping means,
cylindrical work tube drive means, and means for controlling the
motion of the forming rollers during formation of the tank ends,
and with only a fragmentary portion of the cylindrical work tube
being illustrated, the balance being cut away in order to better
illustrate the details of the structure;
Fiyure 6 i~ a vertical sectional view taken along the line and
in -the direction oE the arrows 6-6 of Figure 5;
Figure 7 is a vertical sectional view taken along the line and
in the direction of the arrows 7-7 of Figure 5;
Fi~ure 8 is a vertical sectional view taken along the l:lne ~nd
in the direction of the arrc)ws 8-~ of Fig-lre 7, allcl w:Lth Figllrq a
being ~hown on a slicJhtly enlaryed scale;
Figur~ 9 i~ a vertical sectional view ta)cen along the line and
in the direction of the arrows 9-9 o.E Fiyure 5 and illustLatilly
certain Aetails of -the support ancl tlrive rinys employed i~ the
appara-tus, with the drive belt beincJ removed;
Figure 10 is an elevational view of the latch mechanism
employed in the support and drive ring component shown in Fiyure 9;
Figure 11~ is a further view of the grooved support and drive
ring, wlth Figure 11~ being taken along the line and in the
direction of the arrows 11-11 of Figure 10;
Figure llB is a view similar to Figure llA, and illustrating
the timing belt drive ring arrangement employed in the apparatus of
the present invention, with the drive belt being removed;
Figure 12 is a detail end view of the apparatus of the present
invention, with Figure 12 being taken along the line and in the
direction of the arrows 12-12 of Figure 5, with the upper portion
of the cylindrical work tube being cut away, and with Figure 12
being shown on a slightly enlarged scale; and
Figure 13 is a detail sectional view taken along the line and
in the direction of the arrows 13-13 of Figure 12, and illustrating
the features of the roller arm supporting the guicle rollers for the
cylindrical work tube.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In accordance with the preferred embodiment of the present
invention, and with par-ticular attention being directed to Figures
1 and 2 of the drawings, the apparatus for the production of
double-ended vessels generally designated lO comprises frame means
11 includiny a primary base mounting pad 12 containing an elongated -
~ 3~
axial guideway or rail along with a plurality of opposed pairs of
cJuideways lncludiny a first pair oE opposed gu.ldeway~ :l.3 ancl 1~,
alOr)y with a secolld pair of opposed yu:Ldeways 16 and 17. '~heSQ
yuideways are g~nerally ec~ually and oppositely disposed relative t~
-the cen~er of the apparatus 10. Each of the guldewavs 13 and :l4
inc:Lude a ~er;les oP superimposed or staclced slidable plates, wi~h
guideway 13 inc:l.udiny slidable plates :l3~, 13B and 13C. sim:Llarly,
guideway 14 includes slidable plates 14A, 14B and 14C. .51idable
plates 13~ and 14A are movable along an axis tr~,nsverse to the
elongated axis oE support 11! while pla-tes 13B, 13C, 14B and 14C
are each movable along axes parallel to the elongatecl axi.s o e
support 11. In order to permit full expansion oE the system to
accommodate tanks of various lengths, it has been found useful to
incorporate plural slidable pads movable along the same axis, such
as pads or plates 13B and 13C, along with opposed pads 14B and 14C.
In this fashion, pads 13C and 14C may be used for establishing a
static set-up dimensional placement for the device, while plates
13B and 14B may be utilized for establishing a fine tuning or
dynamic adjustment. Heating torch articulating means 18 and 19 are
provided at each end of the production apparatus 10, with the torch
articulating means 18 and 19 being secured to a fir~t opposed pair
of secondary base mounting pads 20 and 21. Means are provided for
adjustably securing a heating torch to the articulatiny means, witl
heating torches being illustrated as at 22 and 23 respectively. As
will be indicated hereinafter, secondary base mounting pads 20 and
21 are arranged to support, articulate, and control the programmed
movement of the tube forming rollers employed in the spinning
operation.
With continued attention being directed to the heating
torches, and as indicated in Figure 1, a flame is shown
- 6 -
sc~lematically at 22~ and 23A, with these flames being direc~ed
toward alld imp~ CJincJ clirectly UpOIl the s~lrface oE cylindr:Lcal work
tuhe ge.lleraLly cles:LcJnated 24. Ag .Inclica~ed, flames emitted from
lleating torches 22 and 23 lmpincJe upon encls port:lons 25 and 26
respectively o~ cyl:i.ndrica]. work tube 24.
W.Lth contillued attention belng dlrec~ed to FicJure 1 of the
drawings, cylinclrical work tube guide arms 28 and 29 ara each
secured to a second opposed pair of secondary base mountiny pads 16
and 17, with the cylindrical work tube guide means being adapted to
adjustably and releasably position the cylindrical work tube 2
within the apparatus 10 As is apparent ~rom the view oE Figure 2,
cylindrical work tube guide means, including guide rollers 30 and
31 are arranged to guidingly contact guide ring 32, at spaced
arcuate dispositions therealong. In the end view of Figure 2, the
guide riny 32 is disposed about-`the outer periphery of cylindrical
work tube 24.
As is apparent in Figures 1 and 2, guideways 13 and 14 are
designed for accommodating linear motion along a pair of axes, as
illustrated in double-headed arrows 34-34 (Figure 1), along witll
guideways 35 and 36, also illustrated in Figure 1. Thus, primary
base mounting pad assemblies 13 and 14 are designed to accommodate
linear or translatory motion along two axes arranged at right
angles, one to the other.
The heatiny torch articulating means is illustrated in Figures
1 and 2, particularly with movement available from guideways 34,
35, and 36. In this connection, both the heating torches 22 and
23, along with forming members such as forming rollers 40 and 41
are desiglled to move along those two axes for the base pads 13 and
14. Thus, the heating torch articulating means and the forming
rollers move as a unit, thereby providing for ease of control of
~,~J~ ?,~,
-tempera-ture of tha-t portion of the cyli.nclr:Lcal worlc tube 2~ beinc
subjected to tlle metal sp:inni.llg oper.at:Lorl.
Wlth attentLon bei.ny cl.irected to Figure 2 of the drawlngs, i~
:is sometimes dee.irable -to prov:ide a means ~or rotat:lng formilly
ro:Ller.s such as forming rollers 40 and 41. Variable speed motors
are provided as at ~ ancl 43, wi-th the mo~or speQd being desiylled
to rotate Eorming rollers 40 and 4:l to provide subs~antially
matching rates of speed between the contacting surfaces of work
tube 24 and forming rollers 40 and 41 regardless o~ radial
disposition, thus avoidiny galling. In lieu o~ the variable speed
motors 42 and ~3, a belt drive from a remote motor may be employed
to rotate forming roller6 40 and 41 at appropriate speeds. ~ belt
and pulley arrangement is illustrated in Figure 5, such as at 42A
and ~3A. Rollers 40 and 41 may be rotated about the vertical axis
of member 42 if desired and as indicated in Figure 4.
~s is further apparent from the view of Figure 2, gulde
rollers 30 and 31 are adapted to be adjustably positioned in
accordance with the double-ended arrow 46. By controlling the
angular disposition of guide support arms 28 and 29, the
appropriate working height for work tube 24 is provided. As the
angular dlsposition between guide arms 28 and 29 is increased, the
tube axis is moved downwardly and laryer diameter work tubes may be
introduced into the apparatus and subjected to metal spinning
operations therewithin.
With continued attention being directed to Figures 1 and 2 of
the drawings, it will be observed that cylindrical work tube drive
and grippiny means are arranged as shown generally at 50, with the
work tube drive and gripping means being located or positioned
generally intermediate of the production apparatus 10, and between
opposed pads 20 and 21. Tube drive and gripping means include a
d ~ " ~
hinged guicle ring 51 in which there is recelved a ~e.gmellted or
split spllr gear 52. Gear ~2 may be in tlle ~`orm ot an lnvertecl
timing belt, arld is arranyed to mesh with a second year a~ at 53.
Gear 53 may also be an inver-ted t:Lming belt. ~Iydraulic motor 54 is
designecl to provide the rotational energy through :lts output shaEt
55 to drLve cyL.Incler 56 withln whicll gear 53 i5 retailled . MeallS
ar~. provided for adJustab:l.y position:lng clr:Lve and gripping mean~ 50
along the axis indicated by double-ended arrow 58. Position
adjusting means are shown as at 59, with this position adjustment
means 59 preferably being in the form of a hydraulic cylinder
having a positioning ram as at 60. The extensioll oE ram 60 will,
of course, determine the position of drive gear or bPlt retaining
cylinder 56. Suitable guide and frame means are provided for
cylinder 59, as at 61. As is indicated, cylinder 56 is journably
supported within retaining brackets 62. Cooling means such as
water discharge may be used to protect the holdings means 131-131
and 133-133.
As shown in the drawings, particularly in Figure 1, heat for
the spinning operation is normally provided through heating torches
22 and 23. For applications on smaller diameter vessels, a single
heatiny torch at each end may prove to be adequate. In the event
supplemental heat is reasonably required in the metal spinning
operation, additional heating torches may be provided as at 64-64
and 65-65. A supply of gas for the auxiliary torches is further
indicated as at 66 and 67. Similarly, gas supply for main heating
torches 22 and 23 may be provided as at 68 and 69. Cooling means
in the form of water spray jets may be positioned adjacent to tank
ends for added temperature control.
Attention is now directed to Figures 5 and 6 for an
explanation of the articulating and/or motion-control mechanisms
_ g _
for pads 20 and 21, and accordingly formincJ rollers ~0 arld ~1, as
well as the det~ils Oe the guide rollers 30 and 3:l ~see F'.kJura ~).
With respe.ct to thc g~lide roller mechanisms, :lncludiny support arms
28 and 29, -the axlal location or position of these members is made
possible by mealls of the rotatably mounted threaded shaft 75
work.LncJ within n-lt -76. With aontinued reference to ~:Lyure 6, sha~t
75~ (which may be provided wlth both righ~ and le~t hand threaded
portions) is designed to control the disposition of pad or plate
13C, and thus assist in the overall positioning of certain
components within the assembly. Nut 76 is secured to arms 28~28,
and rotation of shaft 75 in turn controls the axial disposition o~
arms 28 and 29 and rollers 30 and 31. Correspondingly, the opposed
end of the system is provided with threaded shafts 77 and 77A
together with nut assemblies such as at 78 for controlling the
axial disposition of support roll 31 and its mating guide roll on
the opposed side of the cylinder 24. Shaft 77A (not shown) is
utilized in connection with the positioning of pad or plate 14C.
Guide rolls 30 and 31, together with the corresponding pair of
guide rolls (one of which is indicated at 31) adjustably cradle and
support the cylinder 24 for controlled rotation about its
longitudinal axis.
Turning again to the details of the positloning assembly
illustrated in Figure 5, hydraulic motor 80 is coupled to threaded
shaft 75 through coupling 81. Shaft 75 is mounted for rotation
within bearing assembly 82, and includes an extension of threaded
shaft 75 through aligning member 83. A bearing block is indicated
at 84 for preventing axial motion in the rotation of shaft 75. The
opposed end of shaft 75 is received within bearing block 85, and
ultimately within coupling assembly generally shown at 86, along
-- 10 --
d ~ s~ i~
w.i.th coupling sleeve 87 joininy sha:et:s 75 and 77, one to the other.
second bear:incJ bloclc i5 provicled or sha~t 77 as at B~.
Thus, rotational motion of hyclraulic motor 80 causes ro~ation
of oppositely threadecl sha~ts 75 and 77 -to ocaur in unison, thereby
controlling ancl expedi.tiny the pos:ltioniny o~ guide rolls 31-3.1,
along with i~s matiny rolls 30-30 disposed on the aonaealed port:l.on
oE -the view of Figure 5.
In order to provide fine adjustment and operating motion for
the forming roller 40, a computer controlled operating drive means
(not shown) is provided for shaEt segment 90 coupled to threaded
shaft 91 at aoupling member 92. Bearing 93 is provided to enable
appropriate rotation of sha~t 91 and corresponding axial motion of
secondary mounting pad 20 through nut assembly 95. An additional
bearing is provided as at 96 to support the rotation of sha~t 91.
Accordingly, it will be observed that the static ad~ustment X-axis
motion of forming rollers 40 and 41 is controlled through rotation
of shafts 75A and 77A together with their respective mating nut
assemblies.
Turning now to the detail shown in Figure 6, the Y-axis motion
(99A) is created through rotation o threaded shaft 99, with
rotation of threaded shaft 99 being made possible through sha~t
extension 100 which is coupled to a motor (not shown). Nut
assembly 101 is utilized to provide motion directly to mounting
plate 102 as indicated in Figure 6. Accordingly, as the threaded
shaft 99 is rotated within bearings 104 and 105, nut assembly 101
causes linear motion to occur on mounting plate 102. As is
indicated, shaft 99 is disposed at right angles to shaft 91, and
thus appropriate motion in desired directions may be obtained
through controlled rotation of shafts 91 and 99 and their
counterparts. As will be apparent, the oppositely disposed portion
mounted upon and coupled to secondary base mount:lncJ pad 21 :Is a
mirror :image of that arrancJemellt :illustrated in FkJure G. tn otller
words, the apE~a~atus is provicled w:Lth oppositely d:L~posed palrs Oe
metal spinnlng apparatus.
Appropriate proyrammed control may be couplad to the motor
means utilized to dr:ive shaEts 91 ancl 99 ancl their counterparts.
See double-ended arrows 91A (Figure 5) and 99A (Figure 6)
indicating this motion. By appropriately programming the motion or
through the use of servo controlled motors, a family of excursions
may be designed for forming roller 40. These e.xcursions are
designed -to perform the neces~ary metal spinni.ny and formation
opf3rations which will ultimately close the end of tube 24, and form
a closed end as illustrated in phantom in Figure 1 at 106.
Attention is now directed to Figures 7 and 8 of the drawings
which illustrates the drive mechanism, including the cylindrical
work tube drive and gripping means 50. Frame means 110 includes
upper and lower cross-members llOA and llOB. Posts llOC-llOC are
provided with reinforcing gussets, as indicated for example at
llOD. Appropriate corner braces are provided in order to provide
overall stclbility to ~rame means 110. In this arrangement, frame
means 110 supports hydraulic cylinder 111 having a slide or ram 112
coupled thereto, with cylinder 111 being, of course, a double-
acting cylinder. Secured to the distal end of slide or ram 112 is
a clevis arrangement 113 to which is mounted hydraulic motor 54.
Rotation of the output shaft of motor 54, as indicatecl, drives
member 56 which is, in turn, in mesh with gear 52. Vertical
adjustment is provided by ram 112 in order to accommodate and treat
tanks of different diameters.
Attention is now directed to Figure 8 which illustrates
further detalls of the drive mechanism for rotatiny the cylindrical
- 12 -
~ t;3~3~
work cylinder. Hydraulic motor 54 is coupled throuyh couplilly
element 115 to shaEt L16 to wllich drive member l:l7 L~ arrantJad Ln
fa~t rel.lt:Lollship. ~ppropriate be~rings are provided at l:L8 ancl
119 to accommocda-te rotational mo-tion oE shaft 116. A ~econdary
couplincJ is provldecl along shat 116 as at 120 Eor obtaininy data
from encoder 121. Encoder 121 :Ls desicJneA to provicle posit:Lon
feedback data to the system, and also to provide Eor con-trollable
rotational mo-tion to the components system, with suitable encoders
being, of course, commercially available. In certain applications,
hyclraulic cylinder 111 may be an air cylinder, if de~ired.
In orcler to appropriately program the X-Y motion o~ the
forming roller 40, programmed computer servo controlled motor~ may
be employed. Also, the motion control means handling the
positioning of forming rollers, such as roller 40 are desirably
coordinated with the rotational speed of the tank so that lineal
rates of motion between the surface of the tank and roller 40 are
substantially matching.
With attention now being directed to Figure 9, latch system
generally designated 123 is provided in order to tightly grip drive
ring 51 about the outer periphery of cylindrical work tube 24.
Latch system 123 is coupled on either side of parting line 125 i.n
order to achieve appropriate gripping relationship of ring 51 about
tube 24. In most instances, drive ring 51 utilizes latch member
123 with gripping element 126, and with an arcuate spacing of 5
degrees on either side of the parting line, for example, being
designated as appropriate or stable gripping force. The angular
relationship is illustrated in Figure 9.
With attention now being directecl to Figure 10, further
details of the latch mechanism are illustrated. In this
~,d,?,~t~
arrangement it can be seen that latch system 123 incLudes a togcJle
lever :l27 for achiev~ cJ appropria~e c:Losure arran~3eme~
F:igure llA illustrates the deta:L:L oE guide rlny 32. GuLcle
ring 32 is provlcled with a channel æone as at 130 to receive roller
supports 30-30 and 31-31 therewithin. Guicle rings 32-32 alony with
rollers such as at 30-30 and 31-3~ complete that porti.otl o~ the
as~embly. ~uitable o~r:Lnys are provided, such ~s at 13:L for
providing resilient gripping between member 32 and the outer
periphery of cylinder tube 24. Latchiny mechanism 123 is
illus-trated in both Figures llA and llB. For operat:ional
expediency, only one guide ring of the type shown in this Figure
llA need be employed, with the second or opposed guide being in the
form of a flat ring or short cylinder, without flanges 32A-32A
being required to be pr~sent. Of course, for stability of
operation, it may in certain instances be desirable to utilize a
dual set of flanyed members such as are illustrated at 32-32 in
Figure 1.
Figure llB is similar to Figure llA, but illustrating the
detail of drive ring 51. Drive ring 51 may be provided with spur
gear or timing belt 52 about the outer periphery thereof, with belt
52 being a timing belt with the drive teeth turned out. A latch
mechanism such as shown generally at 123 is provided in a manner
similar to that shown in Figure 9, with a small access hole being
cut out of the gear or belt. Also, O-rings are provided as at 133-
133 to achieve appropriate snug gripping between drive ring 51 and
the outer periphery of cylinder tube 24.
It has been observed that the arranyement o~ the present
invention renders it possible to work wikh cylindrical work tubes
of different diameters. For example, tube 24 may have a diameter
ranging from between about 12" and 30", with larger or smaller
- 14 -
tubes being appropriate as well. ~ccordincJly, drive ring 51 along
with other support rings, such as rincJ 32 may be ~bricated in a
family of rings so as to render it possible to work with tube~ o~
cliEferent cllameter. Thus, cylinder 59 may be utlliz~d to both
adjustably accommodate the tubes being treaked, as well a~ to
mainta~ a drLve force Oll the surEace O.e the tube so as to achieve
constant, predictable, and rellab:le ro-tation thereof. Such
rota-tion is, of course, desired in view of the manner :Ln which
force i5 applied to the forming rollers as they move across the
metallic work being spun and/or rotated.
Attention is now directed to Figure 12 oE the drawinys wherein
the support arrangement for the cylinder tube 24 i5 ShOWIl.
Specifically, support rollers 30 and 31 are designed to provide a
cradle mechanism for the tube 24, and the arcuate spacing between
support rollers 30 and 31 is controlled by a pair of right-hand and
left-hand threaded shafts 135 and 136. Shafts 135 and 136 are
right-hand and left-hand threaded segments respectively, and are
joined together at coupling 137. Bearing blocks are provided as at
138-138 for shaft segment 135, and at 139-139 for shaft segment
136. Nut assemblies are provided as at 140-140 to provide
appropriate spacing, and thus angular disposition, with pin
retention slots being provided at 141-141 to achieve angular
control of arms 28 and 29.
Attention is now directed to Figure 13 of the drawings wherein
a further view of the details of the system described in Figure 12
are illustrated. In the arrangement of Figure 13, arm 29 is
designed to pivot about its mount 144 and thus achieve appropriate
location to provide cradle support for cylindrical work tube 24.
Att~ntion is now directed to Figure 4 of the drawings wherein
a typical family of curves are provided for illustrating the
traver~ing ancl/or .sweeping routes of travel of cyl:inclrlcal. worlc
t.~lbe rorm~llcJ rol.Lers ~1() and ~ Ln tlle ~chemal~.Lc l:L~ trakLol) Or
Flgure 4, formincJ roller 40 typlcally trave:ls about an arcuate path
from a point aloncJ the ou-ter periphery o e tube 24 to the
termlnation of Pass Mo. 1, where indicated. PaGs No. 1 is achieved
on a 15" radius, with the~ motion and other movement of. forml.ny
roller 40 beiny achieved by combined and coordinated movement oE
the X and Y axes control. For Pass ~o. 2, forming roller 40
-traverses the path or track identified as Pass No. 2 for return to
a position adjacellt the outer periphery of tube 29. Similarly,
further passe~ are made, as indicated, until the Einal pass is
achieved as defined along Pass No. 11~ ~ 30" radius is normally
utilized at Pass No. 11, in order to achieve the appropriate
configuration for the tank end. The knuckle zone is designed, for
a vessel of 30" diameter to be 3/4", as indicated in Figure 4.
In the event it is desired to employ a modified tilt angle for
forming roller 40 as about vertical axis 42, this may be achieved
as shown in phantom in Figure 4. A tilt angle of lo degrees may,
in certain ins-tances, provide enhance.d performance of the system.
In the event continuous duty apparatus is contemplated, it may
in certain in~tances be desirable to provide a liquid coolant for
the forminy rollers, including forming roller 40. Liquid coolant
may be interposed into the confines of forming roller 40 so as to
achieve cooling as desired. In this arrangement, suitable rotary
couplings are provided in order to preserve the flow of liquid
coolant such as water through the interior of the forming roll.ers,
such as forming roller 40. In order to form the final closure
alony the axis of the tank at opposed ends thereof, a conventional
gas torch may be utilized to heat the metal at and along the
juncture point, whereupon the metal flows inwardly to seal the tank
~"i~3~
closure tiyht. Such techniques are., of course, known in the art
and are commonly practiced by sk:illed artlsalls.
By way of summary and conclusion, thereforQ, it w.Lll be
appreciated that the apparatus illustrated alld descrlbed
hereinabove provides a means Eor achieving formation oE tank ends
.Eor cylindrical pressure vessels by utilizing the tank material
from an oriyillal cyl:i.ndriaa]. tube. The sequent:Lal excu~sion~. or
sweep.ing of the forming rollers as indicated in Fiyure 4 are
undertaken on a basis that the force applied to the forming rollers
during a stroke moving axially outwardly may be more or less or
equal to that applied duriny a s-troke moviny axially inwardly o:f
the tube beiny treated. In this fashion, a substan~ial portion o.~
the i.nwardly directed arcuate strokes will be unde.rtaken at a rate
which is either yreater, less than, or equal to that applied during
the axially outwardly directed stroke. By controlled programminy
of the motion or position of pads 40, or forcas applied thereto and
temperature of the work, control and distribution of the metal
thickness in the head area may be achieved, particularly in the
knuckle area illustrated at 148 in Figure 4. Rotational rates of
speed for the work (tank) may be varied to maintain a substantially
matching rate of speed at the ~orminy roller-tank surface
interface. Increasing the rotational velocity of the tank as the
forminy roller 40 moves radially inwardly achieves this result ancl
also increases production rates throuyh a reduction in cycle time.
It will be appreciated, therefore~ that the details provided
herein are yiven for purposes of illustration only and not to be
construed as a limitation upon the scope of the appended claims.
What is claimed is:
