US2950525A

US2950525A - Tube puller

Info

Publication number: US2950525A
Application number: US757337A
Authority: US
Inventors: Edward J Duncan; Anthony S Ciminero
Original assignee: Individual
Current assignee: Individual
Priority date: 1958-08-26
Filing date: 1958-08-26
Publication date: 1960-08-30
Anticipated expiration: 1977-08-30

Description

United States Patent TUBE PULLER Edward J. Duncan, 446 Vera Ave., Redwood City, Calif., and Anthony S. Ciminero, 11 /2 Chenery St., San Francisco, Calif.

Filed Aug. 26, 1958, set. No. 757,337

7 Claims. (Cl. zs-as'z This invention relates to improvements in tube pullers.

The principal object of this invention is to provide a device for extracting tubes from the tube sheet of a condenser, heat exchanger or the like.

A further object is to produce a device which is adaptable to various sizes of tubes Within the range of the device.

A still further objectis to produce a device which is readily portable so that the same may be moved from one working location to another.

A further object is to produce a device which is economical to manufacture and one that will thus be readily available to the trade.

Other objects and advantages will be apparent during the course of the following description.

In the accompanying drawings forming a part of this specification and in which like numbers are employed to designate like parts throughout the same,

Fig. 1 is a side elevation of our tool;

Fig. 2 is an enlarged vertical cross section of Fig. 1; and portions thereof being shown in elevation; and

Fig. 3 is an enlarged perspective view of one of the extracting fingers.

In condensers, boilers, heat exchangers and the like it is customary to employ two end plates commonly known as tube sheets, between which plates tubes extend and have their ends expanded into holes formed inthe plates.

These tubes serve either to conduct heat or water therethrough, depending upon the type of structure.

It often occurs that these tubes, after considerable use, become corroded and pitted and it is consequently necessary to replace them. In order to do so, they must be extracted from the tube sheets and it is for this purpose that we have devised our tool.

It has been found that these tubes in some instances may be used again, either by stretching them, or by cutting the ends ofi, when they can be used in other portions of the structure where shorter tubes may be employed.

It is therefore essential that the tube puller does not mutilate the ends of the tubes or in any other manner injure them.

In the accompanying drawings, wherein for the purpose of illustration is shown a preferred embodiment of our invention, the numeral 5 designates a tubular housing forming a cylinder 6 in which is slidably positioned a holding member 7 having O-rings 8 which serve to frictionally position the holding member at certain times during its travel in the cylinder. The holding member 7 in eludes an annular abutment shoulder 7 for a purpose to become apparent.

Threadedly secured to the end of the tubular housing 5 is a fitting 9 which has a reduced end or nose 11 which is adapted to engage the outer surface of the tube sheet 12.

It is to be here noted that a bore 13 is formed in the nose 11 and is of sufficient diameter to permit the end of the tube 14 to be extracted to be moved thereinto during the withdrawing operation, as to be later described.

Threadedly secured to the end of the holding member 7 is a nipple 16 to the oposite end of which nipple is a collar 17, having an inturned lip 18 against which abuts the shoulder 19 of the extracting fingers 21 and 22. These fingers are kept in spaced position by a sliding Wedge 23 and are held- .thereagainst by an expansible ring 25. Each finger has teeth 24 annularly disposed relative to the longitudinal axis of said sleeves, see Figs. 2 and 3, adapted to engage the inner surface of the tube 14 as will be hereinafter seen. The fingers include flat faces opposite the teeth which are ground to complementary angles to opposite faces of said wedge.

Movable in the holding member 7 is a nut 26 which is threaded into the piston rod 27, which piston rod is secured to the piston 28 slidable in a power cylinder 29 secured to the tubular housing 5 as by bolts' 31. The nut 26 has threadedengagement with a thread 32 formed on the end of the wedge 23. At the other end, the nut includes a terminal shoulder 26' engageable with the inturned abutment shoulder 7 on the end of holding member 7 and accordingly provides a lost motion connection therewith. Power, such as air or hydraulic pressure, may be applied to either side of the piston 23 through the pipes 33 and 34.-

The result of this construction is that when it is desired to extract a tube from the tube sheet, it is first necessary to apply power to the piston 28 through the pipe 34 so as to move all of the movable parts forward or toward the nose 11. The fitting 9 is now rotated by hand upon its thread so that the end of the nose is retracted a sufiicient distance to expose a desired number of the teeth 24 that they may be inserted in the end of the tube ready for extraction. Although a threaded connection is particularly suitable for this purpose, other expedients might prove to be acceptable.

In the next step, the operator ta'kes hold of the exposed end of the wedge 23 and rotates it so that the threaded end 32 will move into the nut 26, thus causing the wedge to further spread the extractor fingers until their diameter, combined with that of the separating wedge, becomes almost that of the interior of the tube to be extracted, so that when power is applied through the pipe 33 to the opposite side of the piston 28, the resultant force will cause the nut 26 to slide, as for instance toward the left of the drawing until its shoulder 26' abuts the shoulder 7' of the holding member 7, during which time the wedge has caused the extractor fingers to be expanded and to firmly grasp the interior end of the tube.

Now further movement of the movable parts will pull the end of the tube 14 into the bore formed in the nose 11, thus extracting the tube from the tube sheet.

It will thus be seen that our invention accomplishes all of the objects above set forth.

It is to be understood that the form of our invention herewith shown and described is to be taken as a preferred example of the same and that various changes relative to the material, size, shape and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the subjoined claims.

Having thus described our invention, we claim:

1. A tube puller comprising a hollow elongated housing, a holding member frictionally mounted in said housing for initial orientation and subsequent longitudinal reciprocation in said housing, a fitting engaged on one end of said housing and longitudinally adjustable to a fixed position thereon, said fitting terminating in a hollow nose for engaging a plate from which a tube is to be pulled and into which the terminal end of the tube will be received, an elongated wedge extending axially into said holding member and nose, said wedge being tapered longitudinally from its terminal end toward said nose and into said housing, a pair of opposed elongated extracting fingers rotatably connected to said holding member and including flat faces each complementary to opposed converging sides of said.wedge, said fingers including longitudinally spaced 'tooth portions opposite 'saiid flat faces, and positionable relative to the terminal end of said nose when said nose is adjusted longitudinallyrelative to said housing, said holding 'member and wedge includingco-i operating engageable portions providing a lost motion; connection therebetween permitting an increment; of

relative movement, and power means connected to said housing and said wedge for initially drawing the wedge axially of said housing, holding member, nose and fingers to first cause said fingers to moveaway from each other a predetermined distance to grip a tube to be extracted from a plate and to subsequently and simultaneously move said holding member and draw said fingers and tube into said hollow nose; said longitudinally adjustable nose permitting a predetermined length of tooth portions to be exposed priorto pulling a tube and s aidiholding member permitting initial relative movement of said wedge with r'espect'to said fingers. r 7 V 2. The structure of claim 1; said wedge being substantially fiat and having opposed flat sides converging toward each other from its terminal end, said fingers includ-' ing longitudinally angular faces engaged'flush on said opposed flat sides.

3. The structure of claim 1; said wedge being threadedly adjustable. axially in said holding member for adjusting said fingers'transversely relative to the longitudinal axis of said wedge. l l

4. The structure of claim 1; said power means comsaid cooperating means.-

5. The structure of claim 1;Tsaid holding member being hollow, an externally threadedni'pple received in said holding member, an annular collar secured to said nipple,

said fingers including a shoulder portion disposed within said annular collar and engaged by said collar, and means engaging said fingers displaceably retaining the same together on said wedge---- i; j V o l 6. The structure of claim 1; said cooperating portions including a shoulder portion on said power means reciprocable in said holding member, said holding member including a shoulder engageable with the'sho'ulder portion on said power means for drawing said holding member away from said nose after the extracting fingers are set.

7. The structure of claim 1; said fitting being threadedly engaged onsaid housing to facilitate longitudinal adjustment thereof with respect to said housing.

' References Cited in the file of this patent UNITED STATES PATENTS 1,735,272 Hand Nov. 12, 1929 1,964,023 Armstrong June 26, 1934 2,438,642 Martin Mar. 30, 1948 2,697,872 Armstrong Dec. 28, 1954