US3864811A

US3864811A - Methods of assembling tube supports

Info

Publication number: US3864811A
Application number: US297482A
Authority: US
Inventors: Frank Walker
Original assignee: Hick Hargreaves and Co Ltd
Current assignee: Hick Hargreaves and Co Ltd
Priority date: 1972-09-20
Filing date: 1972-10-13
Publication date: 1975-02-11
Anticipated expiration: 1992-02-11
Also published as: BE798371A; SE413548B; FR2200462A1; NL7306854A

Abstract

Tubes of a condenser or the like are supported by resilient tubing threaded, while in a flattened evacuated state, between the tubes and then allowed to return to its normal shape to press against the tubes. The tubing is sealed at one end by a detachable clip, or by a plate which stretches the tubing end flat, and the clip or plate is pulled through the tube bundle by a line fed between the tubes by gravity. Alternatively the tubing end is clamped by a tool which is remotely manipulated to push the tool and tubing between the tubes and then to release the tubing end. The tool comprises two relatively pivotable clamping plates each provided with a manipulation rod. The tubing ends are secured in a perforated block at the periphery of the tube bundle, by plugs engaging the tubing ends in the perforations of the block.

Description

United States Patent 1191 Walker METHODS OF ASSEMBLING TUBE SUPPORTS Frank Walker, Stoneclough, England Assignee: Hick, Hargreaves and Company Ltd., Bolton, England Filed: Oct. 13, 1972 Appl. No.: 297,482

Inventor:

References Cited UNITED STATES PATENTS 4/1922 Slocum 81/3 J 3/1956 Watson 29/433 10/1963 Spiro 29/433 9/1968 Ambrose 138/107 X 6/1971 Eaveney 29/270 X 1/1972 7/1972 1451 Feb. 11,1975

3,731,365 8/1973 Fryett 29/241 FOREIGN PATENTS OR APPLICATIONS Primary E.\'am1'ner.lerry W. Myracle Assistant Examiner-Daniel M. Yasich Attorney, Agent, or FirmEric H. Waters 1571 ABSTRACT Tubes of a condenser or the like are supported by resilient tubing threaded, while in a flattened evacuated state, between the tubes and then allowed to return to its normal shape to press against the tubes. The tubing is sealed at one end by a detachable clip, or by a plate which stretches the tubing end flat, and the clip or plate is pulled through the tube bundle by a line fed between the tubes by gravity. Alternatively the tubing end is clamped by a tool which is remotely manipulated to push the tool and tubing between the tubes and then to release the tubing end. The tool comprises two relatively pivotable clamping plates each provided with a manipulation rod. The tubing ends are secured in a perforated block at the periphery of the tube bundle, by plugs engaging the tubing ends in the perforations of the block.

3 Claims, 12 Drawing Figures .DCDO

4/1970 Great Britain 138/112 PATENIEI] FEB1 1 I975 SHEET 2 OF 5 PATENTED 1 W5 3, 864.81 1

SHEET 3 BF 5 &

E y m x FIGQ FlG.2h

PATENTEB FEB] 1 I975 SHEET t 0F 5 METHODS OF ASSEMBLING TUBE SUPPORTS Our British Pat. No. 1188564 relates to a heat exchanger, condenser or other heat exchanged apparatus comprising a tube bundle, wherein the tubes are supported at least partly by resilience of interposed flexible resilient tubing extending generally transverse to and in contact with the tubes, the tubing at least partly embracing the external surface of each tube. Specification No. 1188564 also relates to a method of assembling such apparatus, wherein the tubing is sealed and evacuated whereby the evacuated tubing becomes flattened so that it is easily threaded between the tubes, and the vacuum is then broken, the tubing being impervious to gas. It will be understood that when the vacuum is broken, the flattened tubing will return to its original unflattened state and will therefore press against the tubes by virtue of its resilience, its diameter being greater than the spacing between the tubes.

The present specification is concerned with developments of the aforesaid method, enabling the same to be put into practice.

According to one form of the aforesaid method, one end of the tubing is sealed by a connection member, e.g., a detachable clip, by means of which the tubing is pulled between the tubes of the apparatus. The other end of the tubing is sealed in any convenient way. Preferably the clip is a self-locking over-centre device.

Alternatively said connection member may be a fiat rigid strip e.g. of metal inserted into the said end and of such dimensions as to stretch the tubing essentially flat at the end; the strip therefore forms an at least partial seal, which can be completed if necessary by an adhesive or sealing medium. The said strip is then used to pull the tubing between the tubes of the apparatus.

More specifically, where access is available, say, at top and bottom, or both sides, of a tube bundle, a line e.g., of nylon or similar material is first passed through the bundle, e..g., by attaching the line to a thin flat plate and allowing the plate to fall by gravity, through the bundle. The other end of the line is then attached to a connection member as described above and the evacuated tubing is pulled through and into position in the tube bundle.

Occasionally a tube bundle has staybars, positioned in such a way as to prevent passing of the said thin flat plate and to overcome this problem the following method is adopted. A flexible chain of ball and socket or ball and connecting pin construction having suitable diametral dimensions and sufficient mass to allow the chain to pass by gravity through the tube bundle is fed around the staybar. The chain is passed through the tube bundle and draws behind it a line by means of which the evacuated tubing is drawn through the tube bundle.

Depending on the design of particular heat exchangers it is sometimes not possible to have access at oppo site sides of a tube bundle if for example a baffle plate is adjacent and close to one or more sides of a tube bundle. For installation of the tubing in these circum stances the following method is in accordance with the present invention. An insertion tool made in two or more parts, thin enough to pass through the tube bundle between the tubes, is fitted onto the end of a length of resilient tubing. This causes the end of the resilient tube to be sealed and allows the tubing to be evacuated and therefore collapsed into a flat section. The other end of the tubing is sealed e.g. by alaboratory type pinch clip. The collapsed tubing is pushed into the required position by manipulation of the tool and the insertion tool is removed and withdrawn from the resilient tube bundle leaving the tubing in the tube bundle, the tubing tending to return by virtue of its resilience to its normal circular cross section and thus providing support by making intimate contact with the two rows of tubes between which it passes.

Frequently it is not possible to use a rigid insertion tool because of the limiting confines of the heat exchanger body and in such cases an insertion tool is used having hinges along its length, the hinges being so spaced as to allow the tool to be fed into the tube bundle from a confined space.

The insertion tool consists of two preferably flat clamping members of which one is pivotable on the' other between a first position in which the two members are face to face and form a clip or clamp for sealing the end of the tubing, and a second position in which the tubing is released from between the members or can be inserted for subsequent gripping by the members. Push-rods or bars can be attached to either or both of the members.

According to yet another aspect of the invention, the tubing after insertion between thetubes is secured by one or more perforated blocks, strips or sheets through the perforations in which the tubing passes and which preferably bear against the outer tubes, the tubing being so secured that it cannot move from the perforation back into the tube bundle, e.g. by means of plugs in the tubing ends.

The present invention will be further described with reference to the accompanying drawings, in which:

FIG. 1 shows in perspective a clip used for sealing and manipulation of the end of flexible rubber tubing;

FIGS. 20 to 2i show a tool for sealing the end of the flexible rubber tubing and inserting the tube between tubes of a condenser or the like;

FIG. 3 shows in cross-section a tubing-retaining block; and

FIG. 4 shows schematically the threading operation.

FIG. 1 shows a clip made of steel, consisting of a channel-section member 1 and a hinged member 2 pivoted between the flanges 3 of the member 1. These flanges have pivot holes 4 near their edges near one end of the member 1 which receive lugs 5 projecting from the edges of the member 2 so that the latter can pivot between the flanges. The member 2 at its end adjacent to the lugs 5 has an end flange 6 at right angles to the body of the member and, in the clamping position shown in FIG. 1, substantially at right angles to but slightly spaced from the web portion 7 of the channelsection member 1. The other end of the member 2 is provided with a concave tongue 8 which forms a grip by means of which the member can be lifted and also acts as a stop to limit the pivoting of the member 2 clockwise (as seen in FIG. 1) beyond the gripping position shown.

In use, the tongue 8 is lifted to pivot the other end of the member 2 away from the web 7, and the end of flexible rubber tubing (not shown) which is to be threaded between the tubes of the condenser or the like as disclosed in U.K. Pat. No. 1188564 is inserted between the end of the member 2 and the web 7. The tongue 8 is then pressed down towards the web 7 with the result that the edge 6 of the member 2 presses the tubing against the web 7, flattening and sealing the end of the tubing. Since the edge 6 is on the opposite side of the pivotlugs from the tongue 8 which acts as a stop, an over-centre locking action is obtained which prevents the clip from being released until the tongue 8 is deliberately lifted. That is to say, the resistance of the tubing being gripped holds the clip closed.

A hole 9 is provided in the web 7 at the end remote from the pivot holes 4. In order to permit the rubber tubing gripped by the clip to be threaded between the tubes of the condenser or the like, in accordance with the U.K. Pat. No. 1188564, a thread or line of nylon or the like is first passed between the tubes as described above, for example being weighted by a flat plate of, for example, brass or steel. The trailing end of this line is attached to the hole 9, and the rubber tubing is evacuated so that it becomes flat and readily bendable, its end remote from the clip being sealed in any convenient way, and the line is then used to pull the clip and hence the tubing between the tubes of the condenser. Because of the over-centre arrangement of the clip, the tension in the tubing during this pulling operation will tend to hold the clip closed.

After the tubing has thus been completely threaded between the tubes of the condenser, the clip is released by lifting of the tongue 8, and the other end of the tubing can also be unsealed, so that the tubing will tend to return to its initial round cross-section and thereby press against the tubes of the condenser.

As described above, it may be impossible to use a thread or line to pull the evacuated rubber tubing between the tubes. If this is the case, an insertion tool as shown in FIGS. 2a to 22' can be used. This tool includes a first clamping member 10 shown in plan, side-view and cross-section respectively in FIGS. 2a to 20, and a second clamping member 11 shown in plan, side-view and cross-section respectively in FIGS. 2a to 2f. These members are made of high carbon steel.

The member 10 is generally strip-shaped having a main clamping portion 12 provided along one edge with a chamfered wedging surface 13. At one end of the portion 12 is a flange 14 containing a socket 15. At the other end is a flange 16 containing a pivot hole 17, and a cam 18 which overlies part of the portion 12 and is spaced therefrom, the cam being provided with a chamfered wedging surface 19. The wedging surfaces 13 and 19 are on the same longitudinal edge of the member 10 and, when seen in cross-section as in FIG. 2c, face one another. 1

The member 11 consists ofa strip-like main clamping portion 20 having a chamfered wedging surface 21 along one edge. At one end of the portion 20 is a cam flange 22 provided with a Chamfered wedge surface 23 on one edge. At the other end is a fork 24 provided with a pair of fixing holes 25, and adjacent to this a flange 26 parallel to and spaced from part of the clamping portion 20; a pivot pin 27 extends from the flange 26 to the said part of the portion 20. The wedging surfaces 21 and 23 provided on the same side of the member 11 and, seen in cross-section as in FIG. 2f, face towards one another.

To enable the insertion tool consisting of the members l0 and 11 to be manipulated and thereby passed between the tubes of the heat exchanger or the like, a first manipulating rod 28 (FIG. 2d and 2g) is pivotally secured to the member 10 by a pin 29, and a second manipulating rod 30 (FIG. 2h) is rigidly secured to the member 11 by means ofthe fixing holes 25, the longitudinal direction of the rod 30 being perpendicular to that of the member 11. '3

The way in which the members 10 and II are fitted together is illustrated in FIG. 2d, in which the member 10 and its rod 28 are shown in broken lines. The member 10 is fitted to the member 11 obliquely, the recess 15 engaging the pivot pin 27, as shown by the arrow 32. The respective wedging cam surfaces 19 and 23 are thereby caused to engage each other so as to urge the

members

10, 11 towards each other and

flanges

22, 18 will therefore prevent the members from moving apart from a direction perpendicular to their'planes. The end of the rubber tubing 33 is so placed that it will be gripped between the wedging surfaces 13, 21 as the member 10 is pivoted, and the end of the tubing will therefore be gripped between the

main portions

12, 20 and thereby sealed. The resilience of the tubing, by pressing the

flanges

18, 22 together, will effectively prevent the member 10 from pivoting on the pin 27 and thereby becoming free from the member. 11.

The

rods

28, 30 which are substantiallyparallel, are now used to pass the tool consisting of the members 10, l l and thereby the tubing 33 between the tubes of the condenser, being manipulated simultaneously by an operator. To facilitate this manipulation, a clamp for example as shown in FIG. 2i can be used to clamp the two rods together, between clamping

plates

34, 35 held together by a wing nut 36. As the rods are fed into the tube bundle of the condenser, the clamp is moved in steps towards the operator. To enable the tool and the rods to pass between the tubes of the condenser, the rods are hinged as shown at 37. When the tubing 33 has in this manner been fed through the tube bundle of the condenser, the tubing is released by pivoting of the member 10, this being effected either by hand or remotely by means of the rod 28. The tubing 33, which was previously evacuated and therefore flattened for passage between the tubes, as already described, then returns to its original shape and thereby presses against the tubes.

It is not essential to anchor the tubing, but it is most advisable to do so and for this purpose we use perforated blocks of a plastics or rubber material, preferably a fabric-reinforced rigid resin material. The shape of the retaining blocks is chosen to seat on the arrangement of the tubes at the periphery of the condenser or the like. FIG. 3 shows one possible form of retaining block 40 in longitudinal section, disposed against three external tubes 41 of the condenser or the like. To prevent vibration of the block 40 during operation, O-rings 44 (only one is shown) of for example butyl rubber are fitted to secure the block to the tubes of the condenser. The block shown has two holes 42 aligned with the gaps between the tubes 41, so as to receive the ends of the flexible rubber tubing 33 (only one shown) threaded between the tubes 41. The block 40 shown has legs 43 to support it on the tubes. In case of a longer block these legs may not be necessary since the block can engage several outer tubes 41 lying in a common plane. In cross-section, the block has bevelled or rounded upper edges (not shown) to prevent damage to the 0- rings. The end of the tubing 33 is anchored in its hole 42 by means of a butyl rubber plug 45 which fits into the tubing end within the outer portion of the hole 42; the plug is of greater diameter than the natural internal diameter of the tubing 33, so that the tubing grips the plug and preferably is pressed against the interior surface of hole 42. The design of the butyl rubber plug and the recess in the retaining block is such that minimum distortion is given to and maximum life obtained from the flexible tube 33. This design obviates the use of adhesives which are difficult to apply, prevent easy removal and whose reliability is questionable.

The plug is also so designed that the effects of any impingement from fluids in the condenser or the like are absorbed by the large head of the plug thus preventing damage to the end of the flexible tubing 33.

FIG. 4 shows very schematically how the tubing 33 is emplaced in the bundle of condenser tubes 41, when a tool as in FIG. 2 is not used. A weighting member 47 is attached to a flexible line 46 of nylon or the like and is lowered through the tube bundle. The dimensions of member 47 are such that it can pass readily between the tubes 41 and round any obstruction, e.g., a tie bar in the tube bundle. In FIG. 4 the member 47 is shown as a flat metal plate e.g. of brass, and during passage between the tubes 41 this plate would have its plane parallel to the tubes i.e. perpendicular to the plane of the drawing, not face-on as shown. Alternatively other forms of weight may be used e.g. a metal chain as described hereinabove.

The trailing end of the line 46 is secured to a connection and sealing member 48 which seals one end of the tubing 33, the other end being sealed in any convenient way after evacuation. The member 48 may be a clip as shown in FIG. 1, but in FIG. 4, is illustrated as being a flat rigid metal plate 48 inserted into the tubing end and of such width as to stretch the latter flat and thereby substantially seal it, sealing being completed if necessary by an adhesive or sealing material. The member 48 and tubing 33 are pulled through the tube bundle by means of the line 46, whereafter the member 48 can be removed from the tubing 33 to break the vacuum therein. Like the plate 47, the member 48 will in use have its plane parallel to tubes 41 while passing therebetween.

I claim:

1. In a method of assembling heat-exchange apparatus comprising a metal tube bundle, and flexible resilient tubing threadable between the tubes of said metal tube bundle by means of a detachable clamping and insertion tool adapted to pass between adjacent metal tubes, said tool including two clampingvmembers disposable face to face and of which one is pivotable on the other about an axis substantially perpendicular to the mating faces between a first position in which the two members are face to face so as to form a clip for sealing the end of the resilient tubing, and a second position in which the mating faces are separated and the tubing is released from between the members or can be inserted for subsequent gripping by the members and said tool being provided with remote manipulation means; the improvement comprising: inserting one end of the resilient tubing between said clamping members in the second position of the latter; effecting relative pivoting of said members into the first position thereof to sealingly clamp said one end of the resilient tubing; evacuating said resilient tubing so as to deform the tubing into a flattened condition; sealing the remote end of said resilient tubing; pushing the tool between adjacent tubes of said metal tube bundle by operation of said manipulation means to draw the flattened resilient tubing between said tubes; effecting relative pivoting of said members about said axis into the second operative position of the latter for releasing the resilient tubing from said members and to expand the tubing into its initial configuration; and withdrawing said tool from said metal tube bundle.

2. A method as claimed in claim 1, comprising operating said manipulation means in a remote-controlled sequence for releasing said tool from the end of said resilient tubing.

3. A method as claimed in claim 1, said manipulation means being hingedly connected to said clamping members.

Claims

1. In a method of assembling heat-exchange apparatus comprising a metal tube bundle, and flexible resilient tubing threadable between the tubes of said metal tube bundle by means of a detachable clamping and insertion tool adapted to pass between adjacent metal tubes, said tool including two clamping members disposable face to face and of which one is pivotable on the other about an axis substantially perpendicular to the mating faces between a first position in which the two members are face to face so as to form a clip for sealing the end of the resilient tubing, and a second position in which the mating faces are separated and the tubing is released from between the members or can be inserted for subsequent gripping by the members and said tool being provided with remote manipulation means; the improvement comprising: inserting one end of the resilient tubing between said clamping members in the second position of the latter; effecting relative pivoting of said members into the first position thereof to sealingly clamp said one end of the resilient tubing; evacuating said resilient tubing so as to deform the tubing into a flattened condition; sealing the remote end of said resilient tubing; pushing the tool between adjacent tubes of said metal tube bundle by operation of said manipulation means to draw the flattened resilient tubing between said tubes; effecting relative pivoting of said members about said axis into the second operative position of the latter for releasing the resilient tubing from said members and to expand the tubing into its initial configuration; and withdrawing said tool from said metal tube bundle.