US2708471A

US2708471A - Pipe bending machine

Info

Publication number: US2708471A
Application number: US152252A
Authority: US
Inventors: Sam L Baliard
Original assignee: Individual
Current assignee: Individual
Priority date: 1950-03-27
Filing date: 1950-03-27
Publication date: 1955-05-17
Anticipated expiration: 1972-05-17

Description

May 17, 1955 s. L. BALLARD PIPE BENDING MACHINE 6 Sheets-Sheet 1 Filed March 27, 1950 V/V .V

INVENTORd .Sam L. Bal/ar BY fiAfi/vfi. M 9 fi yf M A orneys- May 17, 1955 s. L. 'BALLARD 2,708,471

PIPE BENDING MACHINE Filed March 27, 1950 6 Sheets-Sheet 2 INVENTOR. .Sam L. Ballard BY fuz br, )3, M

Attorney:

May 17, 1955 s. L. BALLARD PIPE ssmnmc MACHINE Filed March 27, 1950 6 Sheets-Sheet 3 INVENTOR. Sam L. Ballard BY 6. M

Al arneys May 17, 1955 s. BALLARD PIPE BENDING MACHINE 6 Sheets-Sheet 4 Filed March 27, 1950 Fig 9 INVENTOR. 8am L. Ballard BY R m/(Lu )3. W

Afforneys y 7, 1955 s. L. BALLARD 2,708,471

PIPE BENDING MACHINE 6 Sheets-Sheet 5 Filed March 27. 1950 INVENTOR. 50m 1.. Ballard A t torneys May 17, 1955 Filed March 27. 1950 s. L. BALLARD PIPE: BENDING MACHINE 6 Sheets-Sheet 6 This invention relates to a pipe bending machine adapted to bend pipe vertically upward; it also relates to a pipe bending machine adapted to bend pipe against a fixed die as a fulcrum by actuating a strongback to move the pipe into the fixed die and to apply a bending force to one end of the pipe while the pipe is held on the opposite side of the fixed die from said bending force by a holding shoe; and it also relates to the employment of cable and pulley means to move the strongback to bend the pipe.

It is an object of this invention to provide a pipe bending machine having a fixed die as a bending fulcrum to receive an upper portion of the pipe, a holding shoe spaced from the fixed die to receive a lower pipe portion, and a strongback suspended below the fixed die and underextending the fixed die opposite the holding shoe and adapted to move the pipe upwardly into the fixed die, and to have a bending force applied to the underextending portion to bend the pipe.

it is a further object of this invention to provide a pipe bending machine having a fixed die as a bending fulcrum, a holding shoe spaced from the fixed die, and a strongback positioned parallel to the fixed die and extending beyond the fixed die opposite the holding shoe, and cable means adapted to move the strongback to carry pipe therein against the fixed die, and to move the extending strongback portion to bend the pipe around the fixed die as a fulcrum while the shoe holds the pipe.

It is another object of this invention to provide a machine of this class in which the strongback is moved by a driven drum actuated cable loops extending on either side 'of the frame over bending pulleys on the frame and extending strongback end, fulcrum pulleys on the strongback and frame adjacent the inner die end, and snubbing pulleys on the frame and strongback end adjacent the outer die end; the loop being completed below the strongback between the snubbing pulleys.

it is still another object of this invention to provide a machine of this class in which the strongback is moved by a driven drum actuated cable loop extending on either side of the frame over bending pulleys on the frame and extending strongback end, and fulcrum pulleys on the frame and strongback end adjacent the die; the loop being completed below the strongback between the fulcrum pulleys it is still a further object of this invention to provide a machine of this class having a holding shoe which may be adjusted and locked to hold successive sections of bent pipe moved thereinto, and which shoe has means thereon to protect the pipe from being marred by the shoe while unlocked during adjustment.

It is yet a further object of this invention to provide atent a pipe bending machine of this class which is equipped with liners for the strongback and holding shoe to convert these elements to accommodate pipe of lesser than the maximum diameter for which the machine is designed, and which has rollers on either end of the strongback vertically adjustable to permit various diameter pipe to be loaded over the strongback when in lowered position, the inner roller complementing stop means on the other end of the strongback to position the lowered strongback.

It is still a further object of this invention to provide a pipe bending machine of this class having cable ends maintained to extend parallel from flange separated driven drum sections into contact with spacer pulley sheaves mounted on a spring connected bracket pivoted to the frame.

It is yet another object of this invention to provide a pipe bending machine of this class equipped with means thereon for handling the pipe to be bent, as by successively loading portions of pipe into the machine.

It is still a further object of this invention to provide a pipe bending machine of this class having a power means, as an engine thereon for actuating the cable winch, with a platform adjacent thereto from which an operator may control engine and winch.

It is also an object of this invention to provide a pipe bending machine of this class having a fixed die with bed radially curved upwardly and toward the pipe bending end of the machine, the radially extending side surfaces of the die adjacent the bed also being curved upwardly and toward the bending end to avoid contact with the strongback as the pipe is bent.

it is a further object of this invention to provide pipe bending machines of this class having the cable through the bending pulleys actuated by one driving means, as a winch, and having the cable through the fulcrum pulleys, or the combined fulcrum and snubbing pulleys actuated by a separately controlled driving means.

Other and further objects will be obvious when the specification is considered in connection with the drawings in which:

Fig. 1 is a side elevation of one modification of the machine taken along line 1-1 of Fig. 3.

Fig. 2 is a fragmentary, partially diagrammatic side elevation showing bending carried out by the machine of Fig. 1.

Fig. 3 is a plan view of a machine.

Fig. 4 is a sectional elevation taken along line 4-4 of Fig. 3.

Fig. 5 is a forward end view of a machine.

Fig. 6 is a diagram of the bending apparatus of the machine of Fig. 1.

Fig. 7' is a diagram of an optional bending apparatus.

Fig. 8 is a sectional elevation taken along line 88 of Fig. 9.

Fig. 9 is a sectional elevation through a lined die, shoe, or strongback.

Fig. 10 is a side elevation from the opposite side of the machine shown in Fig. 1.

Fig. 11 is a diagrammatic view showing still another optional form of bending. apparatus.

Fig. 12 is a view, similar to Fig. 1, showing the application of the liners to the fixed die,.strongback and holding shoe.

Fig. 13 is a diagrammatic view of another cable, pulley and winch arrangement. I

As shown in Fig. 1, the frame 2 of a pipe bending machine 1 has the lower beams 3 thereof connected by means of the axle 4 to a supporting traction means, as the caterpillar 5 near the rear end 6 of the frame. The skids 7 are connected to support the forward end 8 of the frame and a power traction means may be connected to the skid ring 9 to move the machine from place to place.

The uprights 11, slanted columns 12, and cross-braces 14 support the frame top beams 10 above the beams 3, and as shown in Fig. 3,

cross-beams

15, 16, and 17 crossconnect the beams 10 while suitable corresponding members therebelow cross-connect the beams 3.

The power means, as a suitable internal combustion engine 18, is mounted on the frame top 20, and connected by the drive belt 21 to drive the winch 22. The winch 22 has two

drum sections

23 and 24 separated by the flanges 25, 26, and 27, and outwardly of the journal 28 for the shaft 29, it has a smaller diameter drum section 30 terminating outwardly in the end flange 31.

The cable end 32 is connected to the drum section 23 adjacent the flange 25 and the cable end 33 is connected to the drum section 24 adjacent the flange 2 6. From each drum the cable 35 extends over a pulley or pulley block 36 on the frame end 8 to the pulley 39 on the strongback 40 to a pulley 41 on the strongback to a pulley 42 thereabove on the frame 2 back to the pulley 41 and from thence to the pulley 43 on the strongback and up to the pulley 44 on the frame thereabove, and finally the cable extends under the strongback 48 to complete the loop 45 between the pulleys 44 on opposite sides of the frame 2.

The die or radially curved shoe 46 is removably fixed :1

to the frame below the frame top 20 by means of the cap screws 47 which pass through the

flange feet

48 and 49 of the

cross-beams

15 and 16 respectively. The bed 50 of the die is formed to receive substantially the upper semi-periphery of a pipe portion bent longitudinally to conform to the radius of curvature of the bend.

On the rear portion 6 of the frame 2, the eccentric shaft 51, as shown most clearly in Fig. 4, is journalled in the longitudinally extending journal members 52 between the lower cross-beams 53 and in the journal bracket 54.

This eccentric shaft 51 has the eccentric members 55 rigidly connected thereto to turn in the rings 56 which are rigidly connected to the holding shoe 60.

On one side of the shoe a ring 57 is provided and connected to the frame to extend around the shaft 51.

59 and 61 so that the point 63 may be partially inserted into the spaced radial holes 64 in the ring rim 65. A compression spring 66 is connected at 67 into the rod 62 and extends around the rod to bear against the lug 59 and to normally urge the rod 62 into the ring 57. The handle 68 on the rod 62 is provided for lifting the from one hole 64 so that it may be spaced in another hole.

As demonstrated most clearly in Fig. 2, the shoe 60 has lugs 71 and 72 extending on either side thereof with the top sides 69 and 69' of these lugs being substantially parallel extensions of a lowest point of the bed of the shoe 60. Also, as shown in Fig. 2, the shoe is substantially straight and substantially shorter in length than the fixed die 46. The spring 73 is connected to the frame 2 at 74, as shown in Fig. 4,

and to the inner end 75 of the shoe at 76 near the top thereof as shown in Fig. 3 and Fig. 4.

The rotation of the winch shaft 29 in a clockwise direction, as viewed from the right hand end] of the shaft in Fig. 3 winds up the cable ends 32 and 33 on the

drum sections

23 and 24 respectively. As shown in Fig. 2, after the cable has been actuated to raise the strongback 40 so as to lift the pipe 80 into contact with the die 46, further winding up of the cable bends the pipe into the curvature of the die.

In order to insure that the cable winds up evenly, the pulleys 81 and 82 are provided and mounted on the bracket 83 with disc faces to extend in a horizontal plane; the bracket arm 84 being pivoted at 85 on the crossbeam 17 at the frame end 8. The cable 35 extends from the drum sections most points of the pulley sheaves, the cable end portions extending parallel to each other a distance apart equal to the distanace between the cable connections adjacent the flanges 25 and 26. This spacing tends to insure that the cable winds up evenly on the drum sections.

rod -i.

horizontal plane through the 23 and 24 into contact with the innerthe lugs 71 and 72 on the bed thereunder. sides 113 and 114 of the

lugs

111 and 112 Additionally, the spring 86 is connected to the bracket arm 84 at 87 and to the side of the frame at 88 to normally pull the pulleys in the opposite direction from the direction in which the cable winds up on the drum. This further insures that the cable does not jump about on the drum sections when the winch is first started up.

In operation pipe may be loaded into the machine from either end, but is usually loaded in from the forward end 8. To aid in positioning the pipe axially of the frame 2, the line 98 on the drum section 30 is led over the guide pulley 91 on the top portion of the frame end 8 and extended around the pipe end and connected by means of the hook 92. The winch 22 is then rotated to wind up the cable on the drum section 30 to draw the pipe 80 toward the machine 1.

After the pipe 80 has been placed on the roller 93, it is guided into the frame over the strongback 40 with the strongback bed 94 lowered, as shown in Fig. 1, below the lowermost point 95 of the pipe periphery. To insure that the pipe enters the strongback 40 the guide plates 96 are provided on either side of the strongback end 97. The line 98 is successively disconnected from the pipe 80 and moved outwardly thereon to be re-connected from time to time to assist the operation of loading the pipe into the machine. If, for any reason it might be desirable to load pi e from the end 6 instead of the end 8, an arrangement similar to the guide pulley 91 might be installed at some point on the end 6 outward of the winch 22, or optionally a separately driven winch might be installed on the end 8.

When the pipe has been loaded in over the strongback 48 it makes contact with the vertically adjustable roller 98 at the oppostie end of the strongback from the roller 93. As shown in Fig. 12, the roller 98 is adjustable vertically by a hand wheel 98. In passing it is pointed out that this roller 98 also acts as a positoining stop for the strongback when in lowered position to complement the lug 99 of triangular cross-section fixed beneath the strongback which locates the strongback between the locating plates 101 on the forward part 8 of the frame 2.

After the pipe 80 contacts the roller 98 it may be slid farther on through the machine and into the shoe 60. As the spring 73 tilts the shoe 60 downwardly and inwardly when it is in unlocked position, the lower inner edge 75 of the shoe bed is below the entering end of the pipe, so the pipe passes into the shoe 60 without marring and delaying end to end contact between the pipe and shoe.

When finally loaded and extending outwardly from the shoe 68, the pipe is seen in the position shown by dotted lines in Fig. 1. However, in this regard it should be considered that the liner 102, shown installed in the shoe 6% in Fig. 1, would be omitted to receive the pipe 80 so that the pipe, of the largest diameter for which the machine has been designed, will rest within the bed 103 of substantially semi-peripheral contour of the largest pipe diameter.

The liners 192 are designed for installation in the basic beds of the strongback 4t), die 46 and holding shoe 60,

. as shown in Fig. 12, to convert these elements to receive pipe of smaller diameters. These liners have location pins or dowels 109 thereon to fit corresponding holes 110 in the liners. As shown in Fig. 1 each liner for the shoe 6!) has the

lugs

111 and 112 thereon to correspond with The top extend substantially parallel to the horizontal plane through the lowest point of the liner 182. The liner lugs 111 and 112 have the bars 161 welded on either side thereof to extend below and align these lugs with the shoe lugs 71 and 72.

With the pipe loaded, the operator on the platform 104 initiates the bending operation, the platform being located so that the operator can reach the engine clutch 105, the gear shift 1136, the winch hand clutch 107, and the winch foot brake 198, as well as any other engine or winch controls and brakes, not shown.

It can be presumed for ordinary bending by vertical machines of this class, that broadly six essential elements are required, namely, a frame, a fixed radial die supported from the frame top with bed downwardly, a holding shoe spaced longitudinally of the frame from the fixed die with bed upwardly, a strongback suspendable with bed upwardly sufficiently beneath the fixed die to permit pipe to be loaded between the fixed die and holding shoe and underextending the fixed die in a direction therefrom opposite the holding shoe, a means to lift the strongback with pipe therein upwardly to bring the pipe into contact with the fixed die, and a means to pull up wardly near the outer end of the strongback to bend the pipe into the curved bed of the fixed die while the first means holds up the opposite end portion of the strongback to maintain the pipe therein against the fixed die bed while the holding shoe anchors the pipe portion therein against downward motion as the pipe is bent.

However, when a pipe bending machine is considered which must bend a wide variety of ranges in both wall thickness, pipe material and temper, and diameter, it often happens that a machine designed to bend thick walled pipe has to be modified to bend thin walled pipe. Also, when it is considered that in certain usages of pipe,

as in buried pipe lines which are processed externally against corrosion and other factors, and which are subjected internally to excessive fluid pressures, pipe must be employed which is free of bulges and wrinkles, it can be seen that a delicate control must be provided to bend thin walled pipe without bulging or wrinkling its surface.

In the type of machine shown in Figs. 1, 2. and 6, the bending means employed consists of the

pulleys

36 and 39 which may be termed the pulling or bending block; the

pulleys

41 and 42, which may be termed the squeezing" or fulcrum block; and the

pulleys

44 and 43 which may be termed the snubbing or wrinkle control block. More generically, the combination of

pulleys

41, 42, 44, and 43 may be termed the squeezing or fulcrum block.

When the winch 22 is first rotated, the

pulleys

41, 42, 44, and 43 remain in the vertical plane positions of Fig. 1 as the strongback is lifted upwardly to bring the pipe into contact with the die 46 at the end of its periphery. After this contact is established the strongback begins to bend the pipe into the fixed die and the point of greatest application of the bending moment moves successively upward and to the right along the bed 50 of the die, as shown in Figs. 1 and 2.

When contact between die and pipe has first been established and bending begins, the increased tension on the cable 35 tautens the cable throughout its length and left as the distance between

pulleys

44 and 43 increases faster than the distance between

pulleys

42 and 41 decreases.

The bending force increases as the strongback approaches the end of its upward travel to the right, since, in any one gear, the R. P. M. of the winch remains constant, and consequently the bending moment remains constant. As a result, the bending force increases as the bending radius or arm decreases. At this point the upwardly curved radially extending sides 165 of the fixed die 46 should be noticed, as this feature prevents interference with the strongback. As the point of application of the bending moment moves constantly to the right, as shown in Fig. 2, and toward the pulley 39 on the underextending end of the strongback, the downward pivoting of the pulley 43 with the strongback end 116 opens out the distance between

pulleys

44 and 43. This increased cable length is drawn from the right of pulley 43, as explained hereinabove, and in opposition to the pull to the right which the winch exerts to bend the pipe.

Then, since the strongback is not completely rigid,

but has a certain flexibility therein, the pull of the winch, which resists the spread between

pulleys

44 and 43, tends to wrap the slightly flexible strongback against the pipe to the left of the theoretical point of application of the bending moment, thereby spreading the area of bending, and protecting the thin walled pipe from the wrinkling which otherwise often occurs due to the application of an excessive moment in a very localized area.

As succesive lengths or portions of pipe are bent, the pipe is handled by the line 90, or by any other conventional handling means, as from an A-frame on the top 20 of the frame 2, or by a tractor on the ground in front of the machine 1, and is moved rearwardly through the frame 2 and shoe 60. When this is done, the shoe 60 is unlocked until the next adjustment is completed.

During the positioning of the pipe in the shoe, and when it is unlocked, the pipe may tend to bind at some point in the bed of the shoe, with the result that the shoe may tilt and tend to bring either one or the other edge of the shoe into biting contact with the pipe. The lugs 71 and 72 on the shoe 60 are provided to avoid this as the

top sides

69 and 69 of these lugs pivot upwardly, dependent on the direction of tilt, to contact the under side of the pipe. In cases where the shoe is lined, the

lugs

111 and 112 on the liner 102 serve the same purpose, as the top sides 113 and 114 will contact the pipe, dependent upon the tilt.

When the pipe has been shifted, an operator lifts the handle 68 of the rod 62 against the pressure of the spring 66 and places the rod point 63 in the rim hole 64 corresponding to the higher tilted position of the shoe 60. The pipe is then in position for the next portion in the die to be bent.

The bracket of the caterpillar 5 is trunnioned at 121 .t on the axle 4, and has the trunnion pins 122 at either end upon which the wheels 123 are mounted to rotate. The caterpillar track 124 is belted about the wheels 123 to supply the rear traction contact. Other traction devices, as wheels, may be employed in place of the caterpillar.

This invention is not limited to a machine having the cable and pulley arrangements hereinabove described, but any other arrangement operable on the holding shocfixed die-movable strongback principle is considered, as that shown in Fig. 7. In such an arrangement the winch 22 on the frame 2 has the cable 35 thereon which ex-: tends on each side of the frame, over a pulley 36 on the frame top 20 to a pulley 39 on the strongback 40, to a pulley 131 on the strongback below the fixed die 46, up to the pulley 132 on the frame adjacent the fixed die 46, back to the pulley 131, up again to the pulley 132, and under the strongback 40 to complete the loop of the cable between the pulleys 132.

This arrangement is most applicable to'machines for bending thick walled pipe, as such is not likely to wrinkle or buckle when an excessive bending moment maybe applied at a very localized point. In such arrangement the pulley 132 is best located on the fixed die at some point relatively intermediate the

pulleys

44 and 42 as shown in Figs. 1 and 2.-

As shown in Fig. 11, the arrangement of Fig. 7 may be connected to be actuated by two separately controlled

winches

22 and 135. In this case the winch .22 has the cable 35 extending therefrom over the pulley 132 on the frame adjacent the fixed die 46 and preferably centrally thereof, downwardly to the pulley 131 on the strongback 4t}, upwardly again to the pulley 132, and downwardly under the strongback 40 to complete the loop between the pulleys 132.

The winch 135 has the cable 136 extending therefrom to the pulley 36 on the frame end 8, then downwardly to the pulley 39 on the strongback 40, upwardly to the pulley 36, and then downwardly under the strongback 441 to complete the loop between the pulleys 36. When two winches on the bending end is greater between pulleys than on the squeezing or fulcrum end. It is also obvious that the independently operated winches should be synchronized, at least by co-operation between the two operators of the winches.

The arrangement of Fig. 6 can also be connected to be driven by two separately controlled

winches

22 and 135 as shown in Fig. 13. In such case the winch 22 has cables extending therefrom on either side of the frame to the squeezing or fulcrum pulley 42 on the frame adjacent the forward part of the die 46, and from this pulley the 1 course of Fig. 6 between the pulleys 42, iii, 43, and is followed. The cable path from the forward winch is the same as hereinabove described for the arrangement of Fig. 11.

Throughout the description, the path of the cable be tween pulleys has been broadly discussed without giving consideration to the reeving of the pulley sheaves. Obviously, this invention is not limited to any specific number of cables, it being pointed out only that preferably a greater number of cables should be required between the

pulleys

36 and 39 at the point the pulling force of the winch is applied to the bending arm of the strongback. For instance, in the arrangement of Fig. 6 there are, on each side, five cables between the pulling or bending pul leys, four cables between the fulcrum pulleys, and four cables between the snubbing pulleys.

This invention broadly considers a vertical pipe bending machine in which a downwardly facing fixed die acts as a fulcrum, an upwardly facing shoe holds the pipe at one end of the frame, and an upwardly facing strongback is moved to place the pipe in the fixed die and then is moved upwardly, near the frame end opposite the holding shoe, to bend the pipe.

This invention also broadly considers a pipe bending machine in which a strongback is rocked against pipe in a longitudinally curved fixed die to apply a bending moment against the pipe along a constantly changing point of bending application as the bending arm shortens toward the end of the bend.

This invention also broadly considers a pipe bending machine in which winch operated cables and pulleys, or similar means, may be employed to bend the pipe so that the point of bending moment application moves by infinitesimal lengths along the pipe to be bent.

It is herein pointed out that the locking ring for the holding shoe is subject to variation in construction. For instance, whereas the ring 57 is shown fixed to the frame this ring optionally might be fixed to the side of the holding shoe and equally satisfactory results obtained. In

such case the only difference in operation would rest in :ii

the fact that the ring would be substantially concentric with the center of the eccentric 55 rather than concentric with the axis of the shaft 51.

In this specification it has been stated here and above that the strongback and holding shoe are equipped to :1

have liners installed therein. No mention has been made of installing liners in the fixed die as in practice it has been found more convenient to provide and install a fixed die 46 for each diameter of pipe to be bent rather than to line a basic fixed die of largest diameter each time a smaller diameter of pipe is being bent. However, this practice is optional and the provision of liners in a basic die might be advantageous under certain conditions.

What is claimed is:

l. A pipe bending machine comprising, a frame including a fixed die on its upper part with the under side thereof curved transversely to receive substantially the upper semi-periphery of a pipe to be bent and curved longitudinally to receive a bent length of the pipe, a holding shoe on said frame below and at one end of said die and curved transversely to receive substantially the lower semi-pheriphery of the pipe and hold the same in engagement with said die, a substantially straight strongback curved transversely to receive substantially the lower semi-periphery of the pipe and underextending said fixed die in a direction away from said holding shoe, pulley means on opposite sides and near the ends of said strongback and correponding pulley means on said frame above said strongback, cable means interlaced through said pulley means, and power means for tensioning said cable means to move said strongback upwardly to bring the pipe into contact with and to bend the pipe around said fixed die.

2. A pipe bending machine comprising, a frame including a fixed die on its upper part with the under side thereof curved transversely to receive substantially the upper semi-periphery of a pipe to be bent and curved longitudinally to receive a bent length of the pipe, a holding shoe on said frame below and at one end of said die and curved transversely to receive substantially the lower semi-periphery of the pipe and hold the same in engagement with said die, a substantially straight strongback curved transversely to receive substantially the lower semi-periphery of the pipe and underextending said fixed die in a direction away from said holding shoe; and means adapted to move said strongback into bending contact with the pipe including cable actuating apparatus interconnecting said frame and the end of said strongback adjacent said die and adapted to hold the pipe loaded strongback to maintain the pipe against said fixed die as a bending fulcrum, and separately controlled cable actuating means interconnecting said frame and the opposite end of said strongback and adapted to move it to bend the pipe around said die,

3. A pipe bending machine comprising, a frame including a fixed die on its upper part with the under side thereof curved transversely to receive substantially the upper semi-periphery of a pipe to be bent and curved longitudinally to receive a bent length of the pipe, a holding shoe on said frame below and at one end of said die and curved transversely to receive substantially the lower semi-periphery of the pipe and hold the same in engagement with said die, and a substantially straight strongback curved transversely to receive substantially the lower semi-periphery of the pipe and suspended at one end portion below said fixed die by cable means extending on either side of said frame from a driven drum means on said frame over a first pulley on said frame to a second pulley on said strongback therebelow to a third pulley on said strongback to a fourth pulley on said frame thereabove back to said third pulley back to said fourth pulley, the loop of said cable being completed under said strongback between said fourth pulleys, said other strongback end portion being suspended to underextend said fixed die by cable means extending on either side of said frame from a separately controlled driven drum means on said frame to a fifth pulley on said frame to a sixth pulley on said strongback end portion therebelow back to said fifth pulley, the loop of the last named cable means being completed under said other strongback end portion between said fifth pulleys.

4. A pipe bending machine comprising, a frame including a fixed die on its upper part with the under side thereof curved transversely to receive substantially the upper semi-periphery of a pipe to be bent and curved longitudinally to receive a bent length of the pipe, a holding shoe on said frame below and at one end of said die and curved transversely to receive substantially the lower semi-periphery of the pipe and hold the same in engagement with said die, and a substantially straight strongback curved transversely to receive substantially the lower semi-periphery of the pipe and suspended at one end portion below said fixed die by cable means extending on either side of said frame from a driven drum means on said frame over a first pulley on said frame to a second pulley on said strongbaclr therebelow back to said first pulley, the loop of said cable means being completed under said strongbacl; between said first pulleys, said other strongbacl; end portion being suspended to under-- extend said fixed die by cable means extending on either side of said frame from a separately controlled driven drum means on said frame to a third pulley on said frame to a fourth pulley on said strongback end portion therebelow back to said third pulley, the loop of the last named cable means being completed under said other strongback end portion between said third pulleys.

5. A pipe bending machine comprising, a frame including a fixed die on its upper part with the under side thereof curved transversely to receive substantially the upper semi-periphery of a pipe to be bent and curved longitudinally to receive a bent length of the pipe, a holding shoe on said frame below and at one end of said die and curved transversely to receive substantially the lower semi-periphery of the pipe and hold the same in engagement with said die, and a substantially straight strongback curved transversely to receive substantially the lower semi-periphery of the pipe and suspended to underextend said fixed die in a direction away from said holding shoe by cable means extending successively on each side of said fixed die from driven drum means on said frame to a first pulley thereon to a second pulley therebelow on the end of said strongback away from said holding shoe to a third pulley on said strongback to a fourth pulley thereabove on said frame back to said third pulley back to said fourth pulley, said cable means extending under said strongback between said fourth pulleys, the winding of said cable means on said drum means moving said strongback upwardly to bring the pipe into contact with and to bend the pipe around said fixed die.

6. A pipe bending machine comprising, a frame including a fixed die mounted thereon with the under side thereof curved transversely to receive substantially the upper semi-periphery of a pipe to be bent and curved longitudinally to receive a bent length of the pipe, a holding shoe mounted on said frame below and at one end of said die and curved transversely to receive substantially the lower semi-periphery of the pipe and hold the same in engagement with said die, a substantially straight strongback curved transversely to receive substantially the lower semi-periphery of the pipe, means adapted to move said strongback upwardly into bending contact with the pipe to bring it into contact with and to bend the pipe around said fixed die, liner means installable in said fixed die, strongback, and holding shoe as adaptations to accommodate the pipe to be bent when such pipe is of smaller diameter than the maximum diameter pipe for which the machine is designed, and roller means on said frame between said holding shoe and said strongback and adapted for vertical adjustment to permit pipe to be loaded into said machine over the lowered position of said strongback and to accommodate various sizes of said liner means.

7. A pipe bending machine comprising, a frame including a fixed die on its upper part with the under side thereof curved transversely to receive substantially the upper semi-periphery of a pipe to be bent and curved longitudinally to receive a bent length of the pipe, a holding shoe on said frame below and at one end of said die and curved transversely to receive substantially the lower semi-periphery of the pipe and hold the same in engagement with said die, a substantially straight strongback curved transversely to receive substantially the lower semi-periphery of the pipe and suspended to underextend said fixed die in a direction away from said holding shoe by cable means interlaced through pulley means on each side of said frame and on each side and near each end of said strongback and connected to driven drum means adapted to pull on the ends of said cable means to move said strongback upwardly to bring the pipe into contact with and to bend the pipe around said fixed die, said pulley means on said frame including pulleys on opposite sides thereof above pulleys near the end of said strongback away from said holding shoe, a pair of spaced apart pulleys with disc faces horizontally supported centrally of said frame adjacent said drum means by bracket means pivoted horizontally on said frame, said drum means including flange separated sections on which the cable means ends can wind and unwind, the spacing between the inner points of said pulleys being the same as the spacing between said cable means ends as they are wound on the respective flange separated sections of said drum means, said ends extending from said sections parallel and into contact with the inner points of said pulleys and then outwardly to said pulleys on said frame.

8. A pipe bending machine comprising, a frame including a fixed die on its upper part with the under side thereof curved transversely to receive substantially the upper semi-periphery of a pipe to be bent and curved longitudinally to receive a bent length of the pipe, a holding shoe on said frame below and at one end of said die and curved transversely to receive substantially the lower semi-periphery of the pipe and hold the same in engagement with said die, and a substantially straight strongback curved transversely to receive substantially the lower semi-periphery of the pipe and suspended to underextend said fixed die in a direction away from said holding shoe by cable means interlaced through pulley means on each side of said frame and on each side and near each vend of said strongback and connected to driven drum means adapted to pull on said cable means to move said strongback upwardly to bring the pipe into contact with and to bend the pipe around said fixed die, said drum means including a pair of flange separated drum sections for receiving the ends of said cable means.

9. A pipe bending machine comprising, a frame including a fixed die on its upper part with the under side thereof curved transversely to receive substantially the upper semi-periphery of a pipe to be bent and curved longitudinally to receive a bent length of the pipe, 21 holding shoe on said frame below and at one end of said die and curved transversely to receive substantially the lower semi-periphery of the pipe and hold the same in engagement with said die, a substantially straight strongback curved transversely to receive substantially the lower semi-periphery of the pipe and underextending said fixed die in a direction away from said holding shoe, cable means interlaced through pulley means on said frame and on opposite sides and near the ends of said strongback and connected to driven drum means adapted to pull on said cable means to move said strongback upwardly to bring the pipe into contact with and to bend the pipe around said fixed die, said driven drum means including a drum section rotatable to wind up a line extending over guide pulley means on the strongback underextended end of said frame and adapted for connection to the pipe to pull it toward said machine.

10. In a pipe bending machine, the combination of, a

' frame having a fixed die thereon, a strongback suspended to underextend said fixed die and adapted to be moved upwardly to bend pipe in said fixed die, means for moving said strongback upwardly to bring the pipe. into contact with and to bend the pipe about said die, a holding shoe mounted on rotatable eccentric means spaced from the end of said strongback underlying said die, said shoe being substantially straight and shorter in length than said fixed die and curved transversely to receive substantially the lower semi-periphery of the pipe to be bent, locking means on said frame adapted to lock said eccentric means to hold said shoe in different positions as successive bent portions of the pipe are moved into the shoe, and lugs extending longitudinally from either end of said shoe with their top sides constituting continuations of the lowermost pipe receiving surface of said shoe.

11. In a pipe bending machine, the combination, of a frame having a fixed die thereon, a strongbacksuspended to underextend said fixed die and adapted to be moved upwardly to bend pipe in said fixed die, means for moving said strongback upwardly to bring the pipe into contact with and to bend the pipe about said die, a holding shoe mounted on rotatable eccentric means spaced from the end of said strongback underlying said die, said shoe being substantially straight and shorter in length than said fixed die and curved transversely to receive substantially the lower semi-periphery of the pipe to be bent, means for holding said eccentric means in adjusted position, spring means on said frame adjacent the inner end of said shoe and connected thereto to tilt said shoe downwardly and inwardly so as to avoid contact between pipe end and shoe end as a pipe is first moved into said shoe to be bent, and vertically adjustable roller means on said frame outwardly of said strongbacl; ends to receive said lower pipe surface to be guided into said shoe.

12. In a pipe bending machine, the combination of, a frame having a fixed die thereon, a strongback suspended to underextend and to have relative longitudinal movement with respect to said fixed die and adapted to be moved upwardly to bend pipe in said fixed die, means for moving said strongback upwardly to bring the pipe into contact with and to bend the pipe about said die, a holding shoe mounted on rotatable eccentric means spaced from the end of said strongback underlying said die, said shoe being substantially straight and shorter in length than said fixed die and curved transversely to receive substantially the lower semi periphery of the pipe bent, means for holding said eccentric means in adjusted position, and spacing stop means on said frame and said strongback to position said strongback in lowered position on said frame with the end thereof adjacent said holding shoe underneath said die and the other end spaced longitudinally therefrom.

13. In a pipe bending machine, the combination of, a

frame having a fixed curved die thereon, a strongbaclr suspended to underextend said fixed die toward the front of the machine and adapted to be moved upwardly to bend pipe in said fixed die, a holding shoe mounted on the rear end of said machine and adapted to receive substantially the lower semi-periphery of the pipe to be bent, pulley v means on said frame on either side of said die and corresponding pulley means on either side and near each end of said strongback, a winch on said frame, and a cable with ends connected to said winch and extending through said pulley means on either side of said die and through said pulley means on either side of said strongback and forming a loop thereunder, and engine means on said frame connected to drive said winch to tension both ends of said cable and lift said strongback and said pipe against said die and to move said underextended strongback end upwardly to bend said pipe around said die.

14. In a pipe bending machine, the combination of, a frame having a fixed curved die thereon, a strongback suspended to underextend said fixed die toward the front of the machine and adapted to be moved upwardly to bend pipe in said fixed die, a holding shoe mounted on the rear end of said machine and adapted to receive substantially the lower semi-periphery of the pipe to be bent, pulley means on said frame on either side of said die and corresponding pulley means on either side and near each end of said strongback, a winch on said frame, a cable with ends connected to said winch and extending through said pulley means on either side of said die and through said pulley means on either side of said strongback and forming a loop thereunder, engine means on said frame connected to drive said winch to tension both ends of said cable and lift said strongback and said pipe against said die and to move said underextended strongback end upwardly to bring the pipe into contact with and to bend said pipe around said die, and platform means on said frame from which an operator can control said engine and said winch.

l5. A pipe bending machine comprising, a frame including a fixed die on its upper part with the under side thereof curved transversely to receive substantially the 12 upper semi-periphery of a pipe to be bent and curved longitudinally to receive a bent length of the pipe, a holding shoe on said frame below and at one end of said die and curved transversely to receive substantially the lower semi-periphery of the pipe and hold the same in engagement with said die, a substantially straight strongback curved transversely to receive substantially the lower semi-periphery of the pipe and suspended to underextend said fixed die in a direction away from said holding shoe by cable means interlaced through pulley means on each side of said frame and on each side and near each end of said strongback and connected to driven drum means adapted to pull on the ends of said cable means to move said strongback upwardly to bring the pipe into contact with and to bend the pipe around said fixed die, said pulley means on said frame including pulleys on opposite sides thereof above pulleys near the end of said strongback away from said holding shoe, a pair of spaced apart pulleys with disc faces horizontally supported centrally of said frame adjacent said drum means by bracket means pivoted horizontally on said frame, said drum means including flange separated sections on which the cable means ends can wind and unwind, the spacing between the inner points of said pulleys being the same as the spacing between said cable means ends as they are wound on the respective flange separated sections of said drum means, said ends extending from said sections parallel and into contact with the inner points of said pulleys and then outwardly to said pulleys on said frame, and spring means connected at one end to said frame opposite the direction of cable winding on said sections and at the other end to said bracket.

16. A pipe bending machine comprising, a frame including a fixed die curved transversely to receive substantially the upper semi-periphery of a pipe to be bent and curved longitudinally to receive a bent length of the pipe, a holding shoe mounted on said frame below and at one end of said die and curved transversely to receive substantially the lower semi-periphery of the pipe and hold the same in engagement with said die, a substantially straight strongback curved transversely to receive substantially said lower semi-periphery of the pipe and spaced from said holding shoe, and means adapted to move said strongback into bending contact with the pipe with said die serving as the bending fulcrum; said means including pulley means on opposite sides of said die, corresponding pulley means on opposite sides and near the ends of said strongback, cable means reeved over said pulley means, and means for tensioning said cable means to move said strongback upwardly to bring the pipe into contact with and to bend the pipe around said die.

17. A pipe bending machine comprising, a frame including a fixed die on its upper part with the under side thereof curved transversely to receive substantially the upper semi-periphery of a pipe to be bent and curved longitudinally to receive a bent length of the pipe, a holding shoe on said frame below and at one end of said die and curved transversely to receive substantially the lower semi-periphery of the pipe and hold the same in engagement with said die, and a substantially straight strongback curved transversely to receive substantially the lower semi-periphery of the pipe and suspended to underextend said fixed die in a direction away from said holding shoe by cable means extending successively on each side of said fixed die from driven drum means on said frame to a first pulley thereon to a second pulley therebelow on the end of said strongback away from said holding shoe to a third pulley on said strongback to a fourth pulley thereabove on said frame back to said third pulley to a fifth pulley on said strongback to a sixth pulley thereabove on said frame, said cable means extending under said strongback between said sixth pulleys, the winding of said cable means on said drum means moving 13 said strongback upwardly to bring the pipe into contact with and to bend the pipe around said die.

18. A pipe bending machine comprising, a frame including a fixed die on its upper part with the under side thereof curved transversely to receive substantially the upper semi-periphery of a pipe to be bent and curved longitudinally to receive a bent length of the pipe, a holding shoe on said frame below and at one end of said die and curved transversely to receive substantially the lower semi-periphery of the pipe and hold the same in engagement with said die, a substantially straight strongback curved transversely to receive substantially the lower semi-periphery of the pipe and underextending said fixed die in a direction away from said holding shoe, and means for moving said strongback into contact with the pipe and for bending the pipe around the die including cable apparatus reacting between said frame and the end portions of said strongback and tensioning means therefor for moving the latter upwardly and around said die.

19. A pipe bending machine comprising, a frame including a fixed die on its upper part with the under side thereof curved transversely to receive substantially the upper semi-periphery of a pipe to be bent and curved longitudinally to receive a bent length of the pipe, a holding shoe on said frame below and at one end of said die and curved transversely to receive substantially the lower semi-periphery of the pipe and hold the same in engagement with said die, and a substantially straight strongback curved transversely to receive substantially the lower semi-periphery of the pipe and suspended to underextend said fixed die in a direction away from said holding shoe by cable means interlaced through pulley means on each side of said frame and on each side and near each end of said strongback and connected to driven drum means adapted to pull on said cable means to move said strongback upwardly to bring the pipe into contact with and to bend the pipe around said die.

20. A pipe bending machine comprising, a frame, a die mounted on said frame having its under side curved transversely to receive the upper side of a pipe to be bent and curved longitudinally about an axis above and remote from said frame to receive a bent length of the pipe, holding means on said frame at one end of and below said die and disposed on the under side of the pipe to hold the same in engagement with said die, a substantially straight for moving said strongback into contact with the pipe and .i

for bending the pipe around the die including cable means on said frame and said one end of said strongback for lifting the latter to bring the pipe into contact with said die and to hold the same thereagainst while the pipe is being bent around said die, additional cable means r on said frame and said other end of said strongback to swing the latter around said die and bend the pipe, and means for tensioning said cable means to operate as aforesaid.

21. A pipe bending machine comprising, a frame, a die mounted on the upper part of said frame having its under side curved transversely to receive the upper side of a pipe to be bent and curved longitudinally about an axis above and remote from said frame to receive a bent length of the pipe, holding means on said frame at one end of and below said die and disposed on the under side of the pipe to hold the same in engagement with said die, a substantially straight strongback curved transversely on its upper side to receive the under side of the pipe and disposed with one end coextensive with and underlying said die and the other end extending away from said holding means, pulley means on opposite sides of said strongback at said one end and corresponding pulley means on said frame on opposite sides of said die, additional pulley means on opposite sides of said strongback and corresponding pulley means on said frame, cable means interlaced through said pulley means, and means for tensioning said cable means to move said strongback upwardly toward and around said die to bring and hold the pipe into contact with said die and to bend the pipe about said die and said remote axis.

22. A pipe bending machine for use along a pipeline right of way where a minimum of space is available for handling large diameter pipe comprising, an elongated frame, a die mounted on the upper part of said frame having its under side curved transversely to receive the upper side of a pipe to be bent and curved longitudinally about an axis above and remote from said frame to receive a bent length of pipe, holding means on said frame below and at one end of said die for engaging the under side of the pipe and holding it in engagement with said die, a substantially straight strongback curved transversely to receive the under side of the pipe and underextending said die in a direction away from said holding means, pulley means on opposite sides and near the ends of said strongback and corresponding pulley means thereabove on said frame on opposite sides of said die, cable means interlaced through said pulley means, and means for tensioning said cable means to move said strongback upwardly toward and around said die to bring the pipe into contact with said die and to bend the pipe upwardly about said die and said remote axis.

23. A pipe bending machine comprising, a frame, a die mounted on said frame having one side curved transversely to receive one side of a pipe to be bent and curved longitudinally about an axis remote from said frame to receive a bent length of the pipe, holding means on said frame at one end of said die and disposed on the opposite side of the pipe to hold the same in engagement with said die, a substantially straight strongback curved transversely to receive the opposite side of the pipe and disposed with one end coextensive with said die and the other end extending away from said holding means, and means for moving said strongback into contact with the pipe and to bring the pipe into contact with and for bending the pipe around the die including force applying means connected between the respective opposite sides of said die and strongback to reduce spreading of said sides apart on application of force sufiicient to bend the pipe.

24. A pipe bending machine for use along a pipeline right of way where a minimum of space is available for handling large diameter pipe comprising, an elongated frame, a die mounted on the upper part of said frame having its under side curved transversely to receive the upper side of a pipe to be bent and curved longitudinally about an axis above and remote from said frame to receive a bent length of pipe, holding means on said frame below and at one end of said die for engaging the under side of the pipe and holding it in engagement with said die, a substantially straight strongback curved transversely to receive the under side of the pipe and underextend ing said die in a direction away from said holding means, force applying means reacting between the respective opposite sides of said die and strongback to reduce spreading of said sides apart on application of force sufiicient to maintain said strongback in engagement with the pipe and the pipe in engagement with said die, and force applying means connected to the strongback at a location remote from said holding means to swing said strongback around said die and bend the pipe.

25. In a pipe bender, a support, a curved bending die anchored on the support and having a bend forming face portion, a rockably mounted holding shoe adjacent one end of the die for holding a pipe in engagement therewith, a separate independently mounted stiff straight bending shoe having a part extending toward the holding shoe past the central point of the face of and directly opposing the die and overlying the bend forming face portion and a part projecting beyond the bend forming face portion in a direction away from said holding shoe, said 15 bending shoe being free to move toward and from the die and to roll without slippage along the die, power means comprising two force applying means having spaced independent swinging connections to the bending shoe and spaced independent swinging connection to the support, said force applying means each comprising pulley means mounted on each side of the bending shoe and on each side of said support and cable means connecting the pulley means at the sides of said elements, one of said force applying means being disposed in spaced relation to the holding shoe and in the vicinity of the bending shoe so as to urge a part of the bending shoe directly toward the die to tightly embrace a pipe held therebetween and the other said force applying means being disposed beyond the die on the opposite side from the holding shoe to roll the bending shoe along the die while it is held in said pipe embracing relation with the die, and actuating means connected to said cable means operable to cause said force applying means to act conjointly on the bending shoe.

References Cited in the file of this patent UNITED STATES PATENTS