US3031007A

US3031007A - Pipe flaring tool

Info

Publication number: US3031007A
Application number: US52499A
Authority: US
Inventors: Temple Robert; Ernest E Temple
Original assignee: Mine Safety Appliances Co
Current assignee: MSA Safety Inc
Priority date: 1960-08-29
Filing date: 1960-08-29
Publication date: 1962-04-24
Anticipated expiration: 1979-04-24

Description

April 24, 1952 R. TEMPLEv a1-AL 3,031,007

PIPE FLARING TooL Filed Aug. 29, 1960 2 sheds-sheet 1 W m d" E* LSU IUHUHHIHWIII IN V EN TORS. POBEPT TEMPLE, BYEP/VEJ T E. TEMPLE,

e v- ToP//E Ks,

April 24, 1962 R. TEMPLE ET AL 3,031,007

PIPE FLARING TOOL Filed Aug. 29, 1960 2 Sheets-Sheet 2 1N V EN TORS X ROBERT TEMPLE,

BYE/2NEsTE.7-EMPL5 E Q.` n ummm *n their H TTOEA/Enfs.

United Statee 3,031,007 PIPE FLARING T001.

Robert Temple, Swissvale, and Ernest E. Temple, Murrysville, Pa., assignors to Mine Safety Appiiances Company, a corporation of Pennsylvania Filed Aug. 29, 1961i, Ser. No. 52,4199 6 Jlaims. (Cl. 153-81) This invention relates to tools for flaring the ends of pipes, and more particularly to such tools that are actuated by explosive charges.

In a copending patent application, Serial No. 823,729, tiled June 29, 1959, now Patent No. 2,993,522, several pipe Haring tools are shown that are of the same type as disclosed in this application. After any of those tools has been used, the breechblock is removed and then a special rod is inserted in the rear end of the tool and screwed into a threaded hole in the rear end of the piston so that the piston can be pulled back into its retracted position ready for use again. Retracting the piston in that manner requires the presence and use of the separate retracting ro-d, which may be mislaid or not be present for some other reason.

It is among the objects of this invention to provide an explosively actuated pipe flaring tool, in which the piston can be retracted by a permanent part of the tool, in which the retracting part of the tool holds the piston in its rear position until considerable pressure builds up behind it, and in which sealing gaskets are not required.

The preferred embodiment of the invention is illustrated in the accompanying drawings, in which FIG. l is a plan view of our pipe daring tool;

FIG. 2 is a vertical longitudinal section;

FIG. 3 is a View of the front end of the tool showing the pipe-positioning pin in place;

FIGS. 4 and 5 are cross sections taken on the lines IV-IV and V-V, respectively, of FIG. l; and

FIG. 6 is a view similar to FIG. 2, but showing the tool after its cartridge has been fired.

Referring to FIGS. 1 to 5 of the drawings, a hollow housing 1 has an internally threaded cylindrical rear end, and a front end provided with an open-top pipe-receiving recess 2. Between its ends the housing is open at the top to permit insertion of a die 3 and a die retainer 4. The chamber that receives the die retainer has parallel opposite sides 6. The rear portion of the retainer is provided with a recess having opposed forwardly converging side walls 7 that are engaged by the forwardly converging sides of the die. The die is provided with a central pipe-receiving opening 8, the rear end of which is flared to the extent necessary to provide the desired are on a pipe 9. To permit the die to grip the pipe, as will be explained presently, and also to allow the die to be removed from the flared pipe, the die is made in two parts or segments which are spaced apart laterally along its center. As shown in FIG. 4, the two segments may be held adjacent each other by studs 11 slidably mounted iu bores 12.

The housing 1 is provided directly behind the die with a pair of diametrically opposite holes 13 for receiving a removable pin 14 that serves as a stop or locator for the end of the pipe. That is, the pipe is pushed back through the die until it engages the pin, to insure that the same length of every pipe will be ared. After the pipe has been positioned in this manner, the pin is removed before the tool is operated.

Screwed into the rear end of housing 1 is the enlarged front end of a long tubular holder 16 for sleeve means 17 slidably mounted in the front portion of the holder. Separation of the holder and housing normally is prevented by a locking stud 1S screwed into the wall of the housing and projectingV into its rear end behind the en- Sl? Patented pr. 2d, 1962 larged front end of the holder. Preferably, the sleeve means takes the form of an integral sleeve. Although the chamfered inner end of the sleeve may normally engage the holder, it is preferred to space them apart slightly and to enlarge the inner diameter of the holder, near its front end, and the adjoining portion of the sleeve so that engaging radial shoulders 19 and 20 are formed, by which the sleeve can be moved ahead when the holder is screwed farther into the housing. When that happens, the sleeve will move die 3 forward against the converging walls of the die retainer 4, which will force the two segments of the die toward each other to grip the pipe between them. Then the positioning pin 14 can be removed from the housing. The front end of the sleeve is provided with a pair of notches 22 that receive the pin while it extends through the housing. rI'hey are maintained in alignment with housing holes 13, even when the tubular holder is turned in the housing, by a positioning stud 23 screwed into the wall Vof the housing and extending into a longitudinal slot 24 in the front end of the sleeve.

It is a feature of this invention that the internal diameter of the rear portion of tubular holder 16 behind sleeve 17 is reduced and slidably receives a barrel 26. The front end of the barrel is enlarged and is provided with a rearwardly facing tapered shoulder 27 that normally engages a forwardly flaring seat 28 in the holder. The rear end of the barrel is threaded and extends out of the holder. Screwed onto the barrel far enough so that it is always inside the holder, is a collar 29. At diametrically opposite points, this collar is provided with threaded radial openings, in which the inner ends of straight handles 31 are screwed. These handles extend out through slots 32 extending lengthwise of the tubular holder. The handles permit the barrel to be slid forward and back in the holder, but they keep it from rotating so that a breechblock 33 can be screwed onto its projecting end and up against the rear end of the holder to pull barrel shoulder Z7 back against its seat 2S. Mounted in the breechblock is a tiring pin 34 that can be driven forward by a hammer or the like to detonate a cartridge 36 disposed in a cartridge chamber 37 formed by the rear end of the barrel.

Slidably mounted in sleeve 17 is a piston 40. In front 0f the piston there is pipe-flaring means spaced from the die. This means may be a separate element or, as shown, a forwardly tapered head 41 forming the front end of the piston itself. The taper of head 41 is the same as the flaring rear end of die opening 3. T o provide a good seal between the piston and sleeve, the piston may be provided with a circumferential groove, in which an O- ring 42 is mounted. To normally hold the piston in its rear or retracted position in the sleeve, it is provided with a forwardly extending tapered axial bore 43 that receives and frictionally engages a forwardly tapered projection 44 on the front end of the barrel. There is only a slight taper to the engaging surfaces of the projection and bore so that they can be wedged tightly together by forcing the projection into the bore when the barrel is pushed forward in the holder. The front end of the barrel itself is provided with a plurality of passages 45 that connect the inside of it with a space behind the piston and the sleeve.

When the tool has been loaded and a pipe has been properly positioned in it, with the sleeve pressed up against the die, all as shown in FlGS. 1 and 2, the rear end of firing pin 3d is struck in order to detonate the cartridge. The resulting gases expand through passages 45 in the front end of barrel 26 and drive both the piston 40 and sleeve 17 forward. Since the sleeve already is in engagement with the die but flaring head 41 is spaced from the die, the first thing that will occur is that the die will be driven`forward slightly by the sleeve and thereby caused to grip the pipe so securely that it will not be driven forward through the die when struck an instant later by the flaring head. Consequently, the rear end ofthe pipe will be expanded or flared into the rear end of the die opening as shown in FIG. 6.

The tight tit between the piston and the barrel projection requires considerable gas pressure to be built up behind the piston before it will move forward. This insures high velocity of the piston when it leaves the barrel projection. The same gas pressure forces the barrel backward tightly against its seat 28 and thereby forms a good seal without the use of a sealing gasket.

Before the ared pipe is removed from the tool, the breechblock is removed and then the handles 31 on the barrel are gripped and the barrel is pushed forward to wedge its projection 44 into the tapered bore 43 in the piston. The barrel then is pulled back to its rear position, with the piston moving with it. The tubular holder 16 then is retracted somewhat in housing 1 to permit the pipe and die and die retainer to be removed through the top of the housing. After a new pipe has been inserted in the die and pressed up against positioning pin i4, which has been inserted in the meantime, the tubular holder is screwed tightly into the housing to cause the die to grip the pipe. Then pin 14 is removed, a new cartridge is inserted in chamber 37, and the breechblock is screwed onto the rear end of the barrel. The tool is now ready to tire and flare the end of the pipe.

By connecting pin 14 to the breeckblock by means of a lanyard 47 that is short enough, it can be made impossible to screw the breechblock onto the rear end of the barrel until after the positioning pin has been pulled out of the housing. Consequently, there is no danger of inadvertently tiring the tool while the pin is still in place. The lanyard may be permanently fastened to the tool by running it through a hole 4% through the head of locking stud 18. This also prevents the stud from accidentally coming out of the housing.

According to the provisions of the patent statutes, we have explained the principle of our invention and have illustrated and described what we now consider to represent its best embodiment. However, we desire to have it understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.

We claim:

l. A pipe tiaring tool comprising a die provided with a central pipe-receiving opening aring at its rear end, the die having outer surfaces converging toward its opposite end, sleeve means having a front end engageable being separated into spaced segments slidable forward against said retaining member surfaces, a tubular holder slidably receiving the sleeve means, means connecting said holder with the retaining member for longitudinal adjustment of the holder toward and away from the retaining member, a barrel slidably mounted in said holder behind the sleeve means and having a cartridge chamber at its rear end, removable means at the rear end of the barrel normally holding it in a rear position, said holder when adjusted toward the retaining member being formed to push said sleeve means forward against said die to cause the die to grip the end of a pipe in the die opening, pipe aring means behind the die and normally spaced therefrom, a piston in said sleeve means behind said Haring means, the barrel having an opening connecting said cartridge chamber with the rear ends of the sleeve means and piston, means for firing a cartridge in said chamber to drive the sleeve means and piston forward to move said liaring means into pipe flaring position in the tiared end of the die opening, the front end of the barrel and the rear end of said piston having frictionally engageable surfaces, and means connected with the barrel for manually moving it forward in the tubular holder after removal 0f said removable means, whereby to force said friction surfaces into engagement with each other to permit the piston to be pulled back in the sleeve means.

2. A pipe flaring tool as recited in claim 1, in which the barrel is provided with a rearwardly facing shoulder and said holder has a seat normally engaged by said shoulder.

3. A pipe flaring tool as recited in claim 1, in which said frictionally engageable surfaces are formed by a forwardly tapered projection on the front end of the barrel and a forwardly tapered bore in the rear end of said piston receiving said projection.

4. A pipe iiaring tool as recited in claim l, in which the barrel is provided with a rearwardly facing shoulder and said holder has a seat normally engaged by said shoulder, and said removable means is screwed onto the rear end of the barrel and against the rear end of the tubular holder and holds said shoulder against said seat.

5. A pipe aring tool as recited in claim 1, in which the side of the tubular holder is provided with a longitudinal slot, and said means for moving the barrel forward extends through said slot.

6. A pipe liaring tool as recited in claim 5, in which said removable means is screwed onto the rear end of the barrel and against the rear end of the tubular holder.

References Cited in the file of this patent UNITED STATES PATENTS 2,276,259 Temple Mar. 10, 1942 V2,464,510 Hull Mar. 15, 1949 2,861,623 Frank Nov. 25, 1958 FOREIGN PATENTS 543,506 Great Britain Feb. 27, 1942