US 2631485 A
Description (OCR text may contain errors)
March 17, 1953 o, STUART ETAL I 2,631,485
WRENCH SOCKET Filed Oct. 25, 1951 s Sheets-Sheet 1 INVENTORS. David 0. Sfuarf Roben W. Meek/ n AITQRNEY March 17, 1953 D. o. STUART ETAL 2,631,485
WRENCH SOCKET Filed Oct. 25, 1951. 3 Sheets-Sheet 2 INVENTORS David 0. Stuart Robert W. Mecklin ATTORNEY March 17, 1953 o, STUART E 2,631,485
WRENCH SOCKET Filed Oct. 25, 1951 I 3 Sheets-Sheet 5 ATTORNEY FIG.5
Patented Mar. 17, 1953 WRENCH SOCKET David 0. Stuart, Homewood, 111., and Robert W. Mecklin, Hammond, Ind., assignors to Standard Oil Company, Chicago, 111., a corporation of Indiana Application October 25, 1951, Serial No. 253,151
This invention relates in general to a pulling device and more particularly to an apparatus for pulling plugs from tube headers of the type used in petroleum refinery furnaces and the like.
Tubes of the type used for heating fluids in the petroleum refineries, chemical, and similar installations, usually comprise a plurality of tubes having ends which are expanded or otherwise fastened to tube headers. These headers may be of various forms but they generally include a plug seat on which is seated a removable plug. Arrangements are also provided to hold the plugs on their seats during the use of the furnace. Because of the characteristics of the fluids passed through the tube headers and because of the extremely high temperatures and pressures of the fluids, it is important that the plugs fit very closely to their seats and considerable pressure is therefore exerted on the plugs by the plug holder or collar to assure a leakproof construction.
Following use of the apparatus, it is desired to remove the plugs from their seats for inspection and/or cleaning of the tubes. This is a difficult task, particularly when the fluid is a cokeforming material such as petroleum which binds the plugs to their seats. It is then difficult to remove the plugs without damaging either the plugs or their seats and when such damage occurs expensive repairs are necessary in order to obtain again a fluid-tight seal.
Heretofore it has been customary to loosen the plug collars and then loosen the tube plugs by driving wedge blocks in between the collar and the tube plug draw nut. This latter is a nut threaded to a shank which may be integral with or fixed to the tube plug and passes through the collar. Three-men crews are necessary to remove tube plugs from headers by the sledge hammer-wedge block method, and a very large proportion of the labor required to unhead furnaces can be charged to these crews. It is therefore an object of our invention to provide a simple and rugged device for removing plugs from headers quickly and easily and without damage to the plugs or the plug seats. A further object of the invention is to provide a wrench apparatus which is readily handled by a single laborer. These and other objects and advantages of our invention will be readily understood from the following description of a preferred embodiment thereof taken with the accompanying drawings, wherein:
Figure 1 is an isometric view of a header assembly, having parts of the walls removed, in
which our wrench socket is mounted for removing the furnace tube plug;
Figure 2 is a sectional view of the socket assembly;
Figure 3 is an end view of the socket;
Figure 4 is an isometric view of the jaw assembly employed in the socket illustrated in Figures 1 and 2;
Figure 5 is a section of the jaw assembly illustrated in Figure 4;
Figure 6 is an end view of the jaw assembly illustrated in Figures 4 and 5; and
Figure 7 is an elevation, partly in section, of a header plug and collar assembly.
The pulling device of our invention may be used on any type of apparatus where a removable element has been pressed in to fit such as in wheel pullers and tube plug pullers. However, for the purpose of this description, we will describe an embodiment of the invention in connection with a tube header iii shown in the draw ing and having a plug seat H formed therein. Plug I2 is adapted to seat on plug seat H and is held in fluid-tight relation thereon by the pressure exerted through the tube collar IS. The plug I2 includes a body portion M from which extends a shank i5 which may be formed integral with the body portion Hi or as a separate piece and threaded thereto. The end of shank i5 is threaded to receive nut l5a which is referred to as the tube plug draw nut. The outer face lea of the body portion M is tapered to seat accurately on plug seat I I. The top of the body portion I4 is also tapered to present a conical surface Mb that is adapted to seat with a corresponding surface |3a formed on the bottom of the tube collar IS.
The tube collar l3 has a central bore iii through which the shank !4 passes and has exterior threads ll adapted to engage the tapped end of the header H). The outer surface of the tube collar 13 has a non-circular projection It so that a wrench or other suitable tool may be used to turn the collar 53 against the conical surface Nb of the plug 9 2. When the tube collar I3 is thus tightened, face Eta and seat H co-act to center the plug 12 as well as to force it into fluid-tight contact with its seat i.
The wrench socket, according to this invention, comprises two elements, the tubular shell 2d having a hex socket 2! out in one end and a square socket 22 cut in the opposite end and the jaw assembly 23 Within a contoured bore 24 between the sockets 2i and 22. The jaw assembly 23 comprises four spacer dogs 25, ball pivots 2t and the spreader springs 21.
The operation of the apparatus is to center the wrench socket on a nut lea. As the shell 2% i pushed over the collar nut it, the jaw dogs 25 strike the tube collar l3 and are pushed back into the tubular socket shell 20. As the jaws 2. move back the bored contour surface 24 on the inside of the tubular socket piece 2% forces them into a closed position as shown in Figures 1 and 2. Upon turning the socket 28, the tube header collar l3 moves out along the shank l and the socket jaw dogs 25 are jammed between the collar l3 and the tube plug draw nut Eta on shank it. This causes the tube plug l2 to be withdrawn from the seat ii in the header it as the collar it is turned out of the header.
After the plug l2 has been freed from the seat H, the wrench socket 253 is withdrawn from the collar-tube plug assembly and the draw nut idea on the shank l5 pushes the socket jaw dogs 25 forward along the contour surface 2 3 of the socket piece 26 thereby permitting the springs 27 to spread the jaws 25 as shown in Figure 6. With the jaws 25 in the open position, the socket can be centered on the next collar-tube plug assembly to be removed by the procedure described above.
The jaw assembly 23 is formed of several jaws having concave recesses 28 and 29 on the inner surfaces and a cam means 3! on the outer surface. The assembly 23 can be fabricated by turning the several jaws in one piece and then cutting into the desired longitudinal segments 25. A relatively small bore formed by recesses 28 is adapted to encircle the shank l5 whereas a larger bore formed by the recesses 2Q accommodates the draw nut [5a with shoulder 29a abutting it.
The outer surfaces of the jaws 25 are contoured to provide cam 3i and the socket 2t is provided with an internal annular channel 30 Which is similarly contoured to receive the expanded jaw assembly 23 as illustrated in Figure 2.
The pivoted end of the jaw assembly 23 includes a polished steel ball 26 brazed to one jaw 25 and seated within a ball seat 32 in the adjacent jaw 25. Compression springs 27 extend between recesses 33 and 34 in the adjacent faces of adjacent jaws 25 as illustrated in Figure 6. This spring-loaded assembly 23 is then slidably held within the jaw chamber enclosed by contour surface 24 in the socket element 20 as illustrated in Figure 2.
Our apparatus can be modified for use on different sizes of shanks and draw nuts by adjusting the radial dimensions of the recesses 28 and 29. Likewise, the threaded dimensions of the draw nut. item can be changed to accommodate various sizes of shanks. It is also contemplated that inserts comprising segments of hollow cylinders can be provided for adjusting the operative dimensions of the recesses of a given jaw assembly. In this way a universal or adjustable jaw assembly can be provided. Likewise, it is contemplated that an integral nut and threaded shank may be used for engaging elements corresponding to plug M but in other environments. Thus an ordinarily shankless plug member can be provided with a threaded recess adapted to engage a headed shank and withdrawn as described herein.
Although we have described our invention in terms of a specific example which has been set forth in considerable detail, it should be understood that this is by way of illustration only and that the invention is not limited thereto since alternative embodiments will become apparent to 4 those skilled in the art in view of our disclosure. Accordingly, modifications of our invention are contemplated Without departing from the spirit of the described invention or the scope of the appended claims.
1. A wrench socket including a socket member, an axial bore in said member, an annular channel in said bore, a smooth curved surface between said channel and said bore, and a movable spacer thrust assembly within said socket, said assembly comprising an articulated group of jaw members and a cam surface on the exterior of said assembly.
2. A wrench assembly comprising a socket member, a smooth bore within said member, and an articulated socket jaw assembly arranged for axial movement within said bore, said jaw assembly comprising a plurality of dog elements, means pivoting the dogs at one end of the assembly, spring means remote from said pivoting means adapted to hold the free ends of the pivoted dogs in the assembly in symmetrically spaced array, a cam means on the exterior of said jaw assembly, and an annular groove in said bore adapted to receive said cam means when the said jaw assembly is in its expanded array.
3. A wrench socket apparatus comprising an end socket member, a bore extending longitudinally of said member, an intermediate portion of said bore being of generally cylindrical configuration and of substantial diameter, an annular channel merging with said socket and said intermediate bore, a movable socket jaw assembly within said bore, said assembly comprising a plurality of spring-loaded pivoted jaw members, and a cam means on the exterior of each of said jaw members adapted to enter alternately said channel and said bore whereby the assembly is expanded and contracted.
l. The apparatus of claim 3 wherein the said assembly includes means for pivoting the individual jaws, compression spring means extending between adjacent jaw members and adapted to place said jaws in a spaced array with the cam means in the said channel, and shoulder means on each said jaw member providing an encircling shoulder when the jaw assembly is in a substantial closed array.
5. A wrench socket assembly comprising a socket member, a smooth bore within said member, and an articulated socket jaw assembly movably arranged within said bore, said jaw assembly comprising a plurality of similar elements, means pivoting adjacent ends of the said elements, spring means remote from said pivots adapted to hold the free ends of the assembly in symmetrically spaced array, a cam means on the exterior of said jaw assembly, and an annular groove in said smooth bore adapted to receive said cam means, said jaw assembly being slidable from said groove into said bore whereby the array of jaw elements is contracted to provide an internal shoulder and a connecting bore.
6. In a wrench socket including a socket member and a bore extending longitudinally of said socket member, the improvement comprising an annular channel near one end of said bore, a smooth curved surface merging said channel and said bore, a movable jaw assembly within said socket, said jaw assembly comprising an articulated group of jaw members comprising a plurality of cylinder segments, means for pivoting said segments with respect to each other, compression spring means extending between adjacent faces of said segments whereby said jaw members are normally urged to an expanded array, a shoulder within a recess in one end of said assembly, a bore extending longitudinally from said recess, and a cam surface on the exterior of said assembly.
'7. A wrench apparatus comprising a socket member, a bore extending longitudinally through said member, one end of said bore comprising a non-circular socket, an intermediate portion of said bore being of cylindrical configuration and of substantial diameter, an annular channel merging with said socket and said intermediate bore, a socket jaw assembly movable within said bore and channel, said assembly comprising a 15 plurality of pivoted jaw members, a cam surface on the exterior of each of said jaw members, said cam surface being adapted to enter said merging channel to permit expansion of the jaw assembly, means pivoting adjacent ends of the individual jaws, compression spring means extending between adjacent jaws and adapted to place said jaws in a spaced array with the cam surface in the said channel, and means within each said jaw member providing an abutting shoulder when the jaw assembly is in a substantially closed array.
DAVID C. STUART.
ROBERT W. MECKLIN.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 499,919 Griffin et al June 20, 1893 978,208 Reilly Dec. 13, 1910 2,216,557 McKean Oct. 1, 1940 2,305,637 Ricciardi Dec. 22, 1942 2,496,005 Grant Jan. 31, 1950 2,555,836 Werich June 5, 1951