US3785026A

US3785026A - Method of dismantling tube bundles

Info

Publication number: US3785026A
Application number: US00260443A
Authority: US
Inventors: G Ohmstede
Original assignee: Ohmstede Machine Works Inc
Current assignee: Ohmstede Machine Works Inc
Priority date: 1972-06-07
Filing date: 1972-06-07
Publication date: 1974-01-15
Anticipated expiration: 1991-01-15

Abstract

This invention is related to an improved method for dismantling tube bundles in a manner more efficient than has heretofore been known in the prior art. The tube dismantling method is capable of effectively removing a plurality of tubes at a single time. The improvement is directed towards locating a tube bundle end that has been cut-off to remove a tube sheet, adjacent and in operative relation to a pair of cooperating parallel rollers. An operator is used to feed successive tubes toward the rollers until they are frictionally engaged thereby. The rollers are rotated in a direction to continue the movement of the tubes from the bundle. After a particular row of tubes has been removed, the rollers are remotely controlled so as to move in a plane perpendicular to the axes of the tubes, and thereby position the rollers in operative relation with another row of tubes to be removed.

Description

States Patent/.191 [111 3,785,026 Uhmstede Jan. 15, 1974 METHOD OF DISMANTLING TUBE BUNDLES [5 7] ABSTRACT Inventor: G ohmstede Beaumont This invention is related to an improved method for [73] Assigneez Ohmstede Machine works, Inc dismantling tube bundles in a manner more efficient Beaumont than has heretofore been known in the prior art. The

tube dismantling method is capable of effectivel re- [22] F'led: June 1972 moving a plurality of tubes at a single time. The im- [21] Appl. No.: 260,443 provement is directed towards locating a tube bundle end that has been cut-off to remove a tube sheet, adjacent and in operative relation to a pair of cooperating 52 us. Cl 29/1514, 29/427, 29/558 parallel rollers An 0 cram is used to feed Successive 51 Int cu 823p 15/26 B23p 19/02 1323p 13/04 b d h l h f u [58] Field of Search 29/1524, 558, 202 es mwar t e I ey are y gaged thereby. The rollers are rotated in a direction to 29/200 51/166 continue the movement of the tubes from the bundle. After a particular row of tubes has been removed, the

References Cited rollers are remotely controlled so as to move in a UNITED STATES PATENTS plane perpendicular to the axes of the tubes, and 2,592,946 4/1952 Ohrnstede 51/166 MH thereby position the rollers in operative relation with another row of tubes to be removed. Primary Examiner-Thomas H. Eager Attorney-Cushman, l2arby Cushrnan w 3 Claims 2 Drawing Figures I I 1 l J 6% n E J 'j a E W l l I LA -11 zjx/ll I a E uv PATENTEDJAHSBM 3385.026

- sum 10? 2 Pmmwm 1 m4 SHEET 2 [IF 2 1 METHOD OIF DISMANTLIING TUBE IBUNDL ES DESCRIPTION OF THE PRIOR ART In the refinery and petro chemical industry, tube bundles are commonly constructed with a plurality of tubes mounted into holes of a tube sheet. Tube bundles utilized in such industries, function as heat exchangers. In the servicing and especially in the dismantling of these tube bundles, much time has been consumed in performing laborious and expensive procedures. These procedures normally entail the practice of attaching a winch or a forklift truck to a single tube after the tube has been removed several inches from the tube bundle and thereafter pulling the tubes one at a time. The winch or forklift truck must be moved a distance at least greater than the length of the tube and then moved back again to the tube bundle end so as to be able to pull another single tube. Consequently, such methods consume unnecessary time and use expensive equipment.

The aforenoted disadvantages as well as others, are overcome by the improved procedures of the present invention. The instant invention introduces significant improvements over the prior art by providing a procedure that can be performed at a faster rate in dismantling tube bundles, thereby saving time and money.

SUMMARY OF THE INVENTION Accordingly, it is an object of the instant invention to dismantle a tube bundle by a more efficient method wherein an improved tube pulling apparatus is utilized. The method includes positioning a tube bundle that has an end cut-off so as to expose the ends of the tubes cutoff adjacent to and in operative relation to a pair of parallel cooperating rollers on the tube pulling apparatus. The rollers are adapted to have several types of movements and said movements are all remotely controlled by an operator located at the end opposite the cut-off end. The rollers are moved in a plane perpendicular to the axes of the tubes of the bundle to any selected position where it is desired to feed tubes from the bundle so as to be engaged by the rollers. The rollers have an increased length along their axes so as to accommodate, therebetween, more than one tube from any single row. The operator feeds selected tubes successively towards the rollers. The rollers are actuated to have rotational movement imparted thereto. The rotation and spacing of the rollers produce a gripping force on the tubes to remove the tubes so fed, from the bundle. In addition, if the gripping force on the tubes is desired to be increased, the spacing between the rollers is decreased by remotely controlling the movement of one of the rollers toward the other.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a schematic front elevational view of a machine utilized in practicing the method of the invention;

FIG. 2 is a side elevational view partly in section as seen in the direction of arrows from the line 2--2 of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring first to FIG. 1, there is shown a tube dismantling machine utilized in practicing the method of the instant invention. The machine 10 is comprised of a machine frame F, having two vertical slide columns 12 both secured at their lowermost portions to a lower support base 14. The base 14 is provided with wheels 16 attached thereto and adapted to cooperate with tracks 18, so as to provide the machine 10 with means for movement. Fixedly mounted on the vertical columns 12 at their uppermost portion is a horizontal support 20. Positioned in the middle of the support member is a carriage movement means 21 which includes an electric motor 22 that rotates a drive winch 24 in either of two directions of rotation, as indicated by arrows A. The motor 22 is operatively connected to a remote control power means 25 (see FIG. 2). Also mounted on the support 10 are two freely rotatable pulleys 26 which are so positioned that each of the pulleys 26 is located at each end of the support member. The drive winch 24 has a cable drum 28 connected thereto also as seen in FIG. 2, and attached thereto are ends of a pair of cables 30. The cables 30 are wound upon the cable drum 38 in opposite directions, so that when the winch 24 is rotated in one direction, the cable will synchronously move outwardly from the drum and when rotated in the other direction, will synchronously move inwardly toward the drum. The other ends of the cables are suitably engaged to a movable carriage 32.

The carriage 32 is provided with grooves 34 that are in sliding engagement with guides 36 on vertical columns l2. Rotatably mounted on the carriage, by means to be described later, is an upper friction roller 38 and a lower friction roller 40. These two rollers are parallel to each other and cooperate to provide the necessary frictional gripping force to withdraw the tubes as they are fed therebetween. The rollers are so dimensioned that they have a length along their axes that is greater than the diameter of an end-faced area of the tube bundle. The

rolls

38 and 40 are drivingly connected to shafts 42 and 44, respectively, and can be comprised of a variety of wear-resistant materials.

These two shafts are in turn adapted to be rotatably driven by a pair of hydraulic motors 46, 48, respectively, which are mounted to the sides of the carriage 32. The motors are operated by conventional solenoid valve means (not shown). The valves are in turn operatively connected to the remote control power means 25 and are responsive to the actuation of the latter. The carriage further includes a cross-bar 50 that extends transversely between the vertical columns 12. A gripping adjustment means 51, for movably positioning the the rollers relative to each other includes, an intermittently driven motor 52 which is positioned on the crossbar. Extending from opposite ends in the motor 52 are a pair of shafts 54. Both shafts 54 extend into gear housings 56 which are also suitably secured to the carriage. Gear housings 56 accommodate appropriate gear mechanisms such as worm gears (not shown) that produce rotation and vertical translation of jack screws 58'.

Referring now to FIG. 2, there is shown the other structure which also comprises the gripping adjustment means 51 for positioning the rollers relative to each other. An opening 60 is provided in the side of the carriage 32. This opening furnishes sufficient space for the movement therein of a pair of slide blocks 62. The slide blocks are also provided with conventional bearing means (not shown) that rotatably support the shaft 42 of the hydraulic motor 48. The jack screws 58 are operatively connected with the slide blocks 62, so that upon rotation and vertical translation of the jack screws relative to the gear housings 56, the slide blocks will follow the vertical movement of the jack screws. As can be seen by the arrows B, the jack screws 58 can move either upwardly or downwardly,. thereby: varying the'distance between the rollers 38' and 40 so as to vary the gripping force exerted on the tubes 67 which are fed therebetween.

A cradle means 64 is anchored to the ground by appropriate means (not shown). The cradle can be any type of support which will hold a tube bundle 66 by its baffles 68. In this preferred embodiment, the cradle is an H-beam having its flanges 70 contact the ground and the baffles 68 of the bundle. Placed upon the tube bundle is another cradle 72 in the form of an H-beam. This H-beam is also positioned so as to have flanges 74 thereon, contact the baffles of the bundle. Cables 76 are wrapped around the cradle 72 and are conventionally secured to the ground. The combined effect of the cradles 64, 72 and cables 76 is to effectuate a firm holding or anchoring action on the tube bundle 66, with sufficient force to prevent the entire tube bundle from movement towards the machine 10, when the tubes 67 are withdrawn longitudinally outwardly therefrom, by the cooperating action of the rollers. The tubes are normally frictionally held within a stationary tube sheet 78 and the baffles 68.

The machine is additionally equipped with a locking mechanism 80. The locking mechanism permits the machine to be securely fixed relative to the tube bundle 66 so as to thereby maintain the machine in a stationary position so that it will not be subject to movement during operation thereof. The locking mechanism includes, a brace 82 and a bracket 84 that connects the brace to the machine. The brace 82, further comprises two side walls (one of which is shown) that straddle a rail 86. The rail is disposed between the tracks 18 and is firmly affixed to the ground. Both the legs of the brace 82 and the rail 86 have formed therein apertures 88 and 90, respectively. When it is desired to restrict movement of the machine 10, the apertures 88 and 90 are aligned with respect to each other and a pin (not shown) is inserted therein. Thusly, a simple yet efficient locking action is obtained.

In its preferred embodiment, the method for dismantling the tubes 67 with the apparatus of the present disclosure function in the following manner. First, a floating tube sheet (not shown) is cut-off from the bundle 66. For a more detailed description of cutting off a tube bundle end reference is made to U.S. Pat. No. 2,592,946. The bundle then assumes the configuration, as shown in FIG. 2. For further ease in dismantling the tubes, the stationary tube sheet 78 can also be removed. The bundle is thereafter placed upon the cradle 64, so that only the baffles 68 actually contact the flanges 70 of the cradle 64. The cut-off end 69 of the bundle is located adjacent the cooperating

parallel rollers

38 and 40. Another cradle 72 is then lowered onto the bundle 66 so that its flanges 74, contact the baffles ofthe bundle. Thereafter, chains 76 are wrapped upon the upper cradle 72 and anchored to the ground so as to secure the bundle 66 relative to the ground.

When it is desired to begin the removal operation, an operator stationed at the end 71 opposite the cut-off end 69 manipulates the remote control means 25. The remote control 25, as aforementioned, is operative to effect functioning of the motor 22, the hydraulic motors 46, 48, and the intermittently driven electric motor 52.

The operator, by appropriately manipulating the remote control 25 actuates the motor 22 so as to cause rotation of the drum 28. Depending upon the direction of said rotation of the drum 28, the cables 30 will move synchronously inwardly or outwardly therefrom to thereby raise or lower the

rollers

38 and 40 mounted on the carriage 32. This raising and lowering of the rollers as aforenoted, is performed in a plane perpendicular to the axes of the parallel co-extensive tubes 67. The position of the rollers can be selectively moved to various positions, whereby the space 39 between the rollers is axially aligned with any of several tubes desired to be removed.

The operator, then forcibly drives selected individual tubes 67 successively longitudinally outwardly from the bundle 66 by appropriate means (e.g., pneumatic hammer). The tubes thusly driven are moved a distance sufficient in length unitl they are frictionally grabbed between the cooperating rotating parallel rollers. If it is desired to remove a plurality of tubes from a single row of tubes, other operators forcibly drive on the tubes. The rollers are caused to rotate due to their operative connection with the hydraulic motors 46, 48. The control 25 is manipulated so as to selectively control the operation of the hydraulic motors through the connection with the conventional solenoid valve. The direction of the rotation of the rollers is such that it will aid in continuing to exert a pulling force on the tubes that have been longitudinally moved towards and between the cooperating rollers. The outer peripheries of the rollers each apply a continuous and progressive force along the length of each tube as they are removed from the bundle 66. The applied forces of said roller are directed to the exterior of the tube or tubes 67 by a longitudinal and a transverse component. The forces applied are sufficient in magnitude to grip and press the tubes fed therebetween so as to continue the further longitudinal extrication of the tubes away from the bundle until the tubes have been completely removed from the bundle.

When it is desired to adjust the gripping forces so as to remove tubes that are difficult to extricate from the bundle, the operator, by manipulating the remote control 25 effects movement of said rollers relative to each other. Controls 25 will be operative to cause the intermittently driven motor 52 to function. The shafts 54 of the motor 52 will begin to rotate so as to thereby drivingly move the upper frictional roller 38 towards the lower frictional roller 40, through the agency of the transmission mechanisms found in the gear housing 56 and the simultaneous action of the jackscrews 58 and slide block 62. This increased co-action of the rollers will be sufficient to deform the exterior surfaces of the tubes 67 and provide a more efficient and effective removal force on the tubes.

In view of the aforementioned detailed description, it becomes readily apparent that the method of the present invention is more efficient and economical than previous prior art procedures. The time and cost savings are the result of the increased maneuverability and controlled adjustment of the rollers in the operation of the machine. The number of tubes pulled at a single time is increased because each roller has a length which is large enough to accommodate all the tubes 67 of a single row of the tube bundle 66. The instant invention further provides added maneuverability to the

rollers

38 and 40, by providing them with movement on the carriage 32 in a plane perpendicular to the axes of the parallel tubes. This movement permits the space 39 between the rollers to move to any appropriate end faced area of the tube bundle 66 so as to present the space to various levels of the tubes that are desired to be removed. Additionally, the gripping force applied by each of the rollers to the exterior of the tubes as the tubes are fed therebetween can be varied so as to enhance the removal of the tubes.

Without further analysis, the foregoing will so fully reveal the essence of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features which fairly constitute essential characteristics of the aspects of the contribution to the art and, therefore, such adaptation should be and are intendedto be comprehended within the meaning and range of the equivalence of the claims.

What is claimed is novel and unobvious and desired to be protected by Letters Patent as set forth in the appended claims.

I. A method of dismantling a tube bundle of the type including a multiplicity of co-extensive parallel tubes having their ends engaged within tube sheet members and their intermediate portions extending through a plurality of longitudinally spaced baffle members, which comprises'the steps of cutting off the ends of the tubes adjacent at least one of said tube sheet members to remove the adjacent tube sheet member from the bundle, anchoring the remaining tube bundle so as to prevent movement of the remaining members in response to longitudinal movement of tubes, driving each tube from the end thereof opposite the cut-off end a predetermined distance substantially less then the length thereof, until the exterior periphery of each tube is initially contacted by applied forces having opposed transverse components sufficient to grip each tube therebetweenand complementarylongitudinalcomponents acting in the direction of the longitudinal movement of the tubes, the applied forces cooperate progressively with the exterior periphery of the tube, to continue the direction of the tubes longitudinal movement upon the initial contact by the applied forces on the tubes.

2. A method of dismantling a tube bundle of the type including a multiplicity of co-extensive parallel tubes having their ends engaged within tube sheet members and their intermediate portions extending through a plurality of longitudinally spaced baffle members, which comprises the steps of cutting off the ends of the tubes adjacent at least one of said tube sheet members to remove the adjacent tube sheet member from the bundle, anchoring the remaining tube bundle so as to prevent movement of the remaining members in response to longitudinal movement of tubes, locating cooperating roller means so as to be spaced from and adjacent said cut-off end, selectively positioning the roller means in a plane perpendicular to the axes of the tubes to a position wherein said roller means is in axial alignment, with preselected tubes that are to be moved lon gitudinally, driving each of the preselected tubes from the end thereof opposite the cut-off end a predetermined distance substantially less than the length thereof until the tubes are fed between the roller means, whereby the roller means continue the longitudinal movement 'of the tubes outwardly away from the bundle, and then positioning the roller means in said plane to another position whereby they are in axial alignment with other remaining tubes that are to be fed therebetween.

3. A method as defined in claim 2, wherein the roller means is moved relative to each other to thereby vary the gripping force on the tubes.

Claims

1. A method of dismantling a tube bundle of the type including a multiplicity of co-extensive parallel tubes having their ends engaged within tube sheet members and their intermediate portions extending through a plurality of longitudinally spaced baffle members, which comprises the steps of cutting off the ends of the tubes adjacent at least one of said tube sheet members to remove the adjacent tube sheet member from the bundle, anchoring the remaining tube bundle so as to prevent movement of the remaining members in response to longitudinal movement of tubes, driving each tube from the end thereof opposite the cut-off end a predetermined distance substantially less then the length thereof, until the exterior periphery of each tube is initially contacted by applied forces having opposed transverse components sufficient to grip each tube therebetween and complementary longitudinal components acting in the direction of the longitudinal movement of the tubes, the applied forces cooperate progressively with the exterior periphery of the tube, to continue the direction of the tubes longitudinal movement upon the initial contact by the applied forces on the tubes.

2. A method of dismantling a tube bundle of the type including a multiplicity of co-extensive parallel tubes having their ends engaged within tube sheet members and their intermediate portions extending through a plurality of longitudinally spaced baffle members, which comprises the steps of cutting off the ends of the tubes adjacent at least one of said tube sheet members to remove the adjacent tube sheet member from the bundle, anchoring the remaining tube bundle so as to prevent movement of the remaining members in response to longitudinal movement of tubes, locating cooperating roller means so as to be spaced from and adjacent said cut-off end, selectively positioning the roller means in a plane perpendicular to the axes of the tubes to a position wherein said roller means is in axial alignment, with preselected tubes that are to be moved longitudinally, driving each of the preselected tubes from the end thereof opposite the cut-off end a predetermined distance substantially less than the length thereof until the tubes are fed between the roller means, whereby the roller means continue the longitudinal movement of the tubes outwardly away from the bundle, and then positioning the roller means in said plane to another position whereby they are in axial alignment with other remaining tubes that are to be fed therebetween.