Hand-portable Press For Swagable Pipe Coupling

Abstract

A hand-portable press having hydraulically extendable shoe forming dies for swaging a pipe coupling into pipe joint formation with a contained pipe section. Each die is separately mounted for articulated movement on the inward end of a hydraulically moveable piston and is arcuate on its innermost face with which swaging is effected. Application of hydraulic pressure, by means of a portable hand pump, forces each piston and shoe die thereon inwardly until concentrically uniform swaging of a coupling into a pressure tight pipe joint with contained pipe is effected.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

"Swagable Pipe Coupling," Ser. No. 860,527, filed Sept. 24, 1969, in the name of G. D. Kish and incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. The field of art to which the invention pertains includes the art of pipe joining apparatus and more specifically to such apparatus for effecting a pipe joint between a coupling and contained pipe by inward metal working or deforming of the coupling member against the pipe.

2. The use of couplings and the like for forming of pipe joints is well known. Conventionally, a pressure tight seal between joined pipe sections is formed by means of couplings which employ bolting, threading, or even mechanical crimping. Recently there has been discovered a tubular coupling member, as disclosed in the aforesaid Kish application, and which when uniformly swaged concentrically inward is permanently deformed compressing a gasket into a pressure tight joint with contained pipe thereat.

While hydraulic tools capable of deforming swagable type couplings are known, as exemplified by Smith et al., U.S. Pat. Nos. 1,818,435 and 1,890,016, such tools are characterized by weight and bulk which render them relatively immovable and difficult to maneuver without the aid of an associated supporting structure such as a hoist or the like. Fabrication of pipe joints with such prior tools has consequently been limited to either shop or job site conditions at which the required supporting structure can be readily available. Since literally thousands of pipe joints are for installations located in field trenches or the like or in otherwise sufficiently remote areas to which transportation of such tools is most difficult if not impossible, the use of these prior tools has been severely limited consequently imposing a corresponding limitation on use of the swagable couplings. Moreover, because of relative immobility of these prior tools, direct labor costs attributable to joint formation under adverse conditions such as those described, have long been regarded as excessive if not prohibitive. As a natural result of these high installation costs, the swagable coupling has been at a competitive disadvantage since it is not uncommon to resort to less desirable but less costly joints such as those previously named. Thus, while desirability for using swagable coupling members has been established from the viewpoint of both convenience and cost, it has at the same time been recognized that optimum commercial success of the coupling is dependent on a more ready availability of a tool providing low cost joint formation under more universal conditions of use.

SUMMARY

This invention relates to a novel hand-portable, easily wieldable swaging press for inwardly deforming a coupling member, of a type disclosed in the aforementioned application of Kish, until a pressure tight joint is formed with contained pipe. When constructed in accordance herewith, the press is hydraulically operated by a hand actuated hydraulic pump connected thereto such that the press and pump have a combined carrying weight of approximately 35 pounds. Since such weight can be easily carried and managed by the average workman over long distances, the tool is dependably available on job sites wherever located as to overcome a major handicap of similar purpose tools in the prior art. Not only is the tool hereof increasingly available as compared to tools of the prior art, but by virtue of construction features employing an articulated mounting between the swaging die and associated piston, reliability and uniformity of swaging necessary to ensure proper joint formation is substantially enhanced.

It is therefore an object of the invention to provide a novel press for deforming a swagable pipe coupling member into a pressure-tight pipe joint with contained pipe.

It is a further object of the invention to provide a press as in the aforesaid object which is hand portable rendering it more universally available on job sites than were such similar purpose tools of the prior art.

It is a still further object of the invention to provide a hand-portable coupling swaging press which is relatively more reliable in operation for ensuring proper coupling deformation to substantially enhance utility of such coupling members and contribute to uniformly consistent low cost joint formation.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric view of a coupled pipe joint as formed by the press in accordance herewith;

FIG. 2 is front exterior assembly of the press and a connected hydraulic hand pump;

FIG. 3 is an exterior assembly of the press as in FIG. 2 opened to receive a coupling and pipe to be joined;

FIG. 4 is an enlarged overall assembly of the press in inoperative relation partly in section to facilitate understanding of its operating components;

FIG. 5 is a fragmentary, enlarged view illustrating the shoe die and supporting piston in their most inner extended position;

FIGS. 6 and 7 are enlarged sections in coupling forming relation taken along the lines 6--6 and 7--7 of FIGS. 4 and 5, respectively;

FIG. 8 is a side elevation as viewed along the lines 8--8 of FIG. 4;

FIG. 9 is a sectional elevation, through the latch plate as taken along the lines 9--9 of FIG. 4; and

FIG. 10 is a sectional view taken along the lines 10--10 of FIG. 4.

Referring first to FIG. 1, there is shown swagable coupling designated 10, which has been deformed by means of a press in accordance herewith to form a coupled joint with pipe sections 11 and 12.

The press hereof, designated 15 which will now be described with reference to FIGS. 2-4, is operable by means of a hand pumped hydraulic ram 16 connected thereto via conduits 17, 18 and 19. Ram 16 is of a type commerically available and is operated for generating hydraulic pressure by means of a hand actuated pump lever 20. Knobbed screw 21, when rotated counter-clockwise as viewed in FIG. 2, permits generated pressure to be released. A pressure gauge 22 directly connected to line 17 is sensitive to pressure levels generated by ram 16 and is watched by the operator as an indication of when joint formation is completed as will be discussed below.

Forming the principal supporting structure of the press is a frame comprising a plurality o interconnectable elongaged link members 26, 27, 28 and 29 which together provide an enclosure within which the other components are operable. Each link member, as can be understood with reference also to FIG. 8, is bifurcated at each end forming intervening spaces 30 and 31 to accommodate hydraulic piping and necked down at one end as compared to the other in order to accommodate an interfit with the complementary end of the adjacent link with which it is to be connected. A removable pin 32 secured to handle 34 connects links 28 to 29, while secured pins 33 join links 27 to 28 and 26 to 29 and a secured pivot pin 35 providing a pivot axis for opening the press connects links 26 to 27.

Grip handles 40 and 41, having finger grips 42, enable ready carrying or opening of the press by an operator as required. When the press is closed the opposing ends of handles 40 and 41 abut (see also FIG. 9). At the same time a latch plate 43 secured by means of cap screw 47 in recess 44 between bosses 45 and 46 of handle 40 extends into recess 51 between bosses 49 and 50 of handle 41. In this relation the tongue end of latch plate 43 is resiliently retained by a ball detent 55 urged downwardly by means of compressed spring 56 and acting to define the closed relation of the press for receiving pin 32.

To open the press as in FIG. 3 for receiving a pipe section 11 or 12 and a coupling 10, arm 34 and pivot pin 32 are first removed by laterally withdrawing the latter. By pulling grip handles 40 and 41 in opposing directions, latch plate 43 is then unsnapped from detent 55 and the units separate by pivoting about the axis of pin 35 until opened the required extent. Thereafter the unit is reclosed with pin 32 reinserted placing the press in condition to begin a swaging operation.

Receiving pressured hydraulic fluid from ram 16 via conduits 18 and 19 are elongated guard arms 60 and 61 secured to the backside of links 26 and 27 respectively and each having a centrally open inlet bore 62 in which to receive the connecting end 63 of the fluid supplying conduit. A spring 64 coiled about each conduit end and engaged in helix grooves 65 of the bore wall provides oriented flexibility of the conduit at the point of connection. Hydraulic fluid available at connection 63 is then supplied to each of links 26-29 through elbow 71 and connector 70 into tapped inlet socket 68 formed in the central portion 67 of the adjacent link. In turn links 28 and 29 receive fluid via intermediate piping connection 74 series connected to their inlet sockets 68 from tapped outlet sockets 69 of links 26 and 27 respectively.

Openly communicating with each of sockets 68 and 69 in central link portion 67 is a bored cylinder 77 for containing a piston 90 and extending with its axis oriented radially inward of the press and laterally offset from the longitudinal direction of the link. As can be appreciated, the axes of all cylinders are angularly displaced symetrically about the frame 90.degree. to each other. Inwardly depending in each cylinder is a boss 78 coaxially bored at 79 and counterbored at 80 to contain a pin 81 projecting downward beyond the boss a distance determined by the adjustable setting of set screw 82. Annular resilient 0-ring 85 and back-up ring 86 each contained in annular pin recess 87 ensure against leakage of hydraulic fluid past the pin.

Piston 90 is contained in cylinder 77 for movement in a radial direction toward and away from the press center. Near the rear or upper end of the piston is an annular groove 91 in which is contained an annular 0-ring 92 and annular backup-ring 93 providing for sliding seal engagement against the cylinder wall. As can be best seen in FIGS. 4 and 5, the piston backside where exposed to hydraulic fluid is hollowed at 96 and terminates in a drill-tip apex 97 at which to engage the end of pin 81. The projection extent of pin 81 when bearing against apex 97 thereby defines the innermost piston position ensuring an open clearance 98 through which fluid communication is maintained at all times between inlet and outlet sockets 68 and 69 for supplying fluid to links 27 and 29 via connections 74. The innermost piston face 100 is spherically shaped for a projected complementary fit into spherical recess 101 of shoe forming die 102 effecting a ball and socket mount enabling articulated or a degree of universal movement therebetween. Annular wiper blade 94 prevents dirt from becoming lodged between the piston and cylinder wall as the piston is withdrawn from its extended position of FIG. 5 to its normally inoperative position of FIG. 4.

Each die shoe 102, as can be seen in FIGS. 4 and 5, is comprised of a body section 111, the upper portion of which contains recess 101 and the lower portion of which contains arcuate forming face 112. Tightly mounting shoe recess 101 against piston 90 while permitting slideable engagement with piston face 100 is a retainer strap 106 encircling the die at the underside of die shoulder 107. The straps in turn connect at opposite ends to coil springs 108 secured at their free ends in a stationary pocket 109. By means of this connection shoe 102 is mounted constantly spring biased toward an axial alignment against the piston but still has the freedom of articulation for reasons as will be explained. At the same time springs 108 provide a spring return of piston and shoe to the relation of FIG. 4 when pressure is released from the relation of FIG. 5.

Die forming face 112 represents an angular extent of substantially 90.degree. for the diameter which occurs when all four shoes are fully extended in the manner of FIG. 5 to then form a substantially continuous circular swaging surface between adjacent shoes. For swaging of coupling members adapted for nominal 2 inch pipe size, the initial unextended inner diameter formed by the separated shoe faces 102 as in FIG. 4 is on the order of approximately three inches. It should be noted at this point that the rear piston area against which hydraulic fluid is operatively effective is substantially greater than the face forming area of its attached die shoe in order to minimize the pressure magnitude required to effect swaging. While the area relationship is subject to variance as a function of material and/or design choices, in a preferred press embodiment for two inch size pipe, the ratio of piston to shoe area is approximately at least 11/2 to 1.

Aiding in initial axial indexing or orientation of the shoes to the deformable coupling section, as can be seen with reference to FIGS. 6 and 7, are radially inward extending rear bumper 113 and front bumper 114. The bumpers are commonly secured to rear and front shoe faces 115 and 116 respectively by means of encircling bumper plate 117 tied in position by wire wrap 118. As shown in FIG. 6, rear bumper 113 extends inwardly of the shoe wall thereat to be received within provided annular coupling recess 119. Outriggers 124, centrally secured to each link at the inboard end of the press and each displaced at approximately right angles to the adjacent outriggers, extend inwardly to a terminal edge 125 slightly displaced from the peripheral coupling surface 126 thereat. In this arrangement the outriggers provide both a visual indication to an operator of substantial coaxial press orientation with respect to the coupling and to prevent signficant angular dislocation or misalignment of the press on the coupling when swaging begins. Each outrigger 124 includes a pair of slots 127 permitting adjustable pre-setting by means of bolts 128. A pair of stop plates 134 at the opposite outboard press end beyond the coupling likewise extend radially inward to near engaging pipe surface 135 further aiding to prevent press misalignment on the coupling when initiating the swaging cycle.

For operating the press, the assembly of FIG. 2 is first brought on a job site at which a coupling member 10 containing a gasket 13 is to be joined to pipe sections 11 and/or 12. Handle 34 and pin 32 are removed enabling the press to be thrown open in the manner of FIG. 3 whereupon the press can be placed in surrounding relation to the coupling and pipe section previously set in joint forming relation. The press is then closed until latch 43 receives ball detent 55 after which handle 34 and pin 32 are reinserted locking the press into its operative relation. After axially indexing the press by means of rear bumpers 113, outriggers 124 and stop plates 134 the swaging operation is ready to begin.

Swaging is initiated by an operator hand pumping ram handle 20 to generate fluid pressure for exerting against each piston 90. As the pressure level builds up all shoes 102 concomitantly begin to move radially inward until engaging the coupling periphery contained generally between the bumpers 113 and 114. Continued pumping further increases the applied pressure which on reaching the yield point of the coupling wall begins concentric swaging deformation thereof uniformly inward toward the pipe. As the coupling constricts, gasket 13 is uniformly compressed into a pressure tight relation between the pipe periphery and the inner surface of the coupling. When sufficient swaging has occurred, the joint formation is completed. While the pressure magnitude required to effect swaging varies with coupling material properties in turn affected by its diameter, it has been found with a piston to shoe area ratio as described above, approximately 7,000 psig is required for nominal 2 inch pipe size. This can be readily sensed by an operator visually watching gauge 22 until 7,000 psig appears thereon upon which knob 21 is opened to release the generated pressure by permitting return of fluid to ram 16. Following release of pressure the pistons and shoes enjoy a spring return after which the press is removed by again withdrawing pin 16. The operator is then ready to proceed to the next joint location and repeat the operating cycle.

By the above description there is disclosed a novel hand-portable press for swaging of coupling joints enabling more universal press application under field conditions previously regarded as unsuitable for forming of such joints. The press is highly reliable and extremely fast enabling a complete joint formation on the order of about an average 4 minutes per joint. Because of articulating swivel movement afforded in the shoe to piston mount, the need for a heavy side frame to resist side thrust is eliminated and the frame need only be adequate to resist radial thrust. Since the forming dies are not fixedly secured to their associated piston face, any binding of the latter which could otherwise occur from unequal loading is clearly avoided while permitting use of relatively short pistons which can be easily centered. Should the press not be initially squared with the coupling, articulating movement of the shoe will still ensure uniform constriction against the coupling. While in a preferred embodiment, the press has been described as having inboard and outboard ends which are different in construction as not to permit interchangeable orientation relative to the coupling, it is obvious that such interchangeable orientation could be provided by having similar construction details at both ends thereof.

Since many changes could be made in the above construction and many apparently widely different embodiments of this invention could be made without departing from the scope thereof, it is intended that all matter contained in the drawings and specifications shall be interpreted as illustrative and not in a limiting sense.

Claims

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A hand-portable swaging press for swagable pipe couplings comprising in combination:

a. a support frame generally forming an enclosure in which to encircle a pipe coupling and pipe to be coupled;

b. fluid inlet means in said frame for receiving pressurized hydraulic fluid;

c. a plurality of hydraulically operable pistons angularly displaced symmetrically about said frame in fluid communication with said fluid inlet means, said pistons each being hydraulically movable concomitantly between a first position maintained in the absence of pressurized hydraulic fluid received at said inlet means to a second position projecting relatively inward of said formed enclosure in response to pressurized hydraulic fluid received at said inlet means;

d. a die shoe on the inward end of each of said pistons, each of said shoes having a die-swaging face of arcuate formation and being maintained at a location displaced from a swagable portion of pipe coupling in said enclosure when said piston is in said first position and swageably engaging against the coupling portion when said piston is caused to move to said second position; and

e. means mounting the die shoes to their respective pistons in a manner providing for relative articulated movement therebetween.

2. A swaging press according to claim 1 including a manually operable hydraulic hand pump having its outlet connected to said fluid means.

3. A swaging press according to claim 1 in which said frame is comprised of a plurality of elongated links interconnectable at their ends.

4. A swaging press according to claim 1 in which each piston of said plurality has a hydraulically responsive area substantially greater than the effective area of die swaging face of the die mounted thereon.

5. A swaging press according to claim 4 in which the ratio of said responsive piston area to said die face area is at least 11/2 to 1.

6. A swaging press according to claim 1 in which said mounting means comprises a ball and socket joint with one of said shoe and piston having an at least partially spherical projection and the other having an at least partially spherical recess for receivably engaging said projection.

7. A swaging press according to claim 6 including biasing means maintaining engagement between each of said shoe and piston and generally urging said shoe to a predetermined alignment therebetween.

8. A swaging press according to claim 6 in which at least one shoe of said plurality includes index means extending radially inward thereof to engage a reference recess surface on a coupling periphery for generally locating said shoes axially relative to the swagable portion of a received coupling.

9. A swaging press according to claim 7 in which at least one shoe of said plurality includes index means extending radially inward thereof to engage a reference recess surface on a coupling periphery for generally locating said shoes axially relative to the swagable portion of a received coupling.

10. A swaging press according to claim 9 in which each of said shoes includes said index means.

11. A swaging press according to claim 9 including a plurality of outriggers angularly displaced about one end of said frame and each projecting inwardly of said formed enclosure to a termination radially adjacent a coupling or pipe periphery thereat for generally effecting an axial coalignment with a received coupling and pipe thereat.