Method and apparatus for making bent pipe

Pipe bending apparatus comprising

• a fixed support,
• a movable support rotatably mounted upon said fixed support,
• means for rotating said movable support to control plane of bend,
• a bending head carried on said movable support, said bending head comprising
• bend and clamp dies mounted for rotation about a bend axis,
• a pressure die mounted adjacent said bend die for pressing the pipe toward said bend die, and
• means for supplying pipe to said bending head, said supplying means comprising, pipe feeding means mounted to said fixed support for continuously grasping said pipe and advancing it toward said bend and clamp dies.

Pipe bending apparatus comprising

• a fixed support,
• a movable support rotatably mounted upon said fixed support,
• means for rotating said movable support to control plane of bend,
• a bending head carried on said movable support, said bending head comprising
• bend and clamp dies mounted for rotation about a bend axis,
• a pressure die mounted adjacent said bend die for pressing the pipe toward said bend die, and
• means for supplying pipe to said bending head, said supplying means comprising, pipe feeding means mounted to said fixed support for advancing pipe toward said bend and clamp dies, said pipe feeding means comprising a plurality of pipe gripping rollers on said fixed support for driving pipe through said feeding means as the pipe is bent.

The method of making bent pipe comprising the steps of

• providing a run of pipe at a supply station,
• withdrawing pipe from said supply station and feeding it to a bending station remote from said supply station,
• employing a plane of bend drive, a distance between bends drive, and a degree of bend drive to position and bend a forward portion of said pipe at said bending station, and
• varying the rates of said drives to decrease change in the length of pipe between said stations.

The method of making bent pipe comprising the steps of

• supplying a continuous length of pipe at a supply station,
• bending a forward portion of said continuous length of pipe at a bending station remote from said supply station,
• guiding the pipe in a pipe storage path from said supply station to said bending station, and
• controlling one of said supply and bending stations to compensate for differences between the rate of bending at said bending station and the rate of pipe supply from said supply station, including the step of feeding pipe to said bending station, said step of controlling comprising synchronously changing the rates of said bending and of said feeding in a sense to decrease changes in the length of said path.

The method of making bent pipe comprising the steps of

• supplying a continuous length of pipe at a supply station,
• bending a forward portion of said continuous length of pipe at a bending station remote from said supply station,
• guiding the pipe in a pipe storage path from said supply station to said bending station, and
• controlling one of said supply and bending stations to compensate for differences between the rate of bending at said bending station and the rate of pipe supply from said supply station, said step of bending including rotating at least a portion of said bending station relative to the pipe in said storage path to control the plane of bend.

Pipe bending apparatus comprising

• a fixed support,
• a machine bed rotatably mounted upon said support,
• a swinging bend arm assembly rotatably mounted upon said bed,
• means for rotating said swinging bend arm assembly,
• said swinging bend arm assembly comprising
• a rotatable arm structure,
• a bend die mounted on said structure,
• a clamp die movably mounted on said structure for motion to and from said bend die to clamp
• a pipe therebetween, and
• means for moving said clamp die,
• a stationary arm assembly carried on said machine bed adjacent said swinging bend arm assembly, said stationary arm assembly comprising
• a pressure bolster mounted for motion toward and away from said bend die,
• a pressure cylinder for driving said bolster,
• a slide movably mounted to said bolster for motion toward and away from said bend die in
• a direction transverse to the motion of said bolster,
• pipe feeding means mounted to said support for advancing pipe toward said bend and clamp dies,
• means for operating said pipe feeding means to control distance between bends, and
• means for rotating said machine bed relative to said feeding means to control plane of bend.

Pipe forming apparatus comprising

• means for continuously bending flat stock into tubular form,
• means for continuously welding said tubular form pipe,
• a terminal station remote from said means for welding,
• means for guiding pipe from said welding means along a non-linear path to said remote terminal station,
• said path having a variable length to accommodate differences in rates of pipe movement at different points along said pipe, said terminal station including means for momentarily stopping motion of pipe at said station, and means for cutting said pipe while said motion is stopped.

Apparatus for making bent pipe comprising

• a source of flat stock,
• means for withdrawing stock from said source,
• means for forming the withdrawn stock into a continuous length of pipe,
• a pipe bending head,
• means for feeding said continuous length of pipe from said forming means to said pipe bending head,
• means for operating said bending head to bend said pipe,
• means for storing a variable length of said pipe between said pipe forming means and said pipe feeding means, and
• means for varying the rate of feed of said feeding means after said bending head has started to bend said pipe.

Apparatus for making bent pipe comprising

• a source of flat stock,
• means for withdrawing stock from said source,
• means for forming the withdrawn stock into a continuous length of pipe,
• a pipe bending head,
• means for feeding said continuous length of pipe from said forming means to said pipe bending head,
• means for operating said bending head to bend said pipe,
• means for storing a variable length of said pipe between said pipe forming means and said pipe feeding means, and
• said bend head including a rotatably mounted head die, clamp die means cooperating therewith to clamp a pipe therebetween and means for rotating said dies to bend pipe around said bend die, and said pipe feeding means including means for grasping the pipe and advancing the pipe toward said bend die, and further including means for controlling said pipe feeding means to advance said pipe at a selectively variable rate whereby the pipe may be bent without stretching by operating the pipe feeding means at a rate equal to the rate at which the pipe moves around the bend die, and whereby the pipe may be bent and simultaneously stretched by operating the feeding means to advance the pipe at a rate less than the rate at which the pipe moves around the bend die.

Pipe bending apparatus comprising

• a fixed support,
• a movable support rotatably mounted upon said fixed support,
• means for rotating said movable support to control plane of bend,
• a bending head carried on said movable support, said bending head comprising
• bend and clamp dies mounted for rotation about a bend axis,
• a pressure die mounted adjacent said bend die for pressing the pipe toward said bend die, and
• means for supplying pipe to said bending head, said supplying means comprising, pipe feeding means mounted to said fixed support for advancing pipe toward said bend and clamp dies, and
• means for controlling the relative rates of said pipe feeding means and said bend and clamp die rotating means to control tension in the pipe as it is bent.

Pipe bending apparatus comprising

• a fixed support,
• a movable support rotatably mounted upon said fixed support,
• means for rotating said movable support to control plane of bend,
• a bending head carried on said movable support, said bending head comprising
• bend and clamp dies mounted for rotation about a bend axis,
• a pressure die mounted adjacent said bend die for pressing the pipe toward said bend die, and
• means for supplying pipe to said bending head, said supplying means comprising, pipe feeding means mounted to said fixed support for advancing pipe toward said bend and clamp dies, and
• means for controlling the relative rates of said pipe feeding means and said bend and clamp die rotating means so as to draw said pipe after bending has begun.

The method of making bent pipe comprising the steps of

• providing a run of pipe at a supply station,
• withdrawing pipe from said supply station and feeding it to a bending station remote from said supply station,
• bending a forward portion of said pipe at said bending station,
• varying the relative rates of said bending and withdrawing to decrease change in the length of pipe between said stations,
• filling said pipe with a solidifiable material, and
• solidifying said material within the pipe before the pipe is bent.

The method of making bent pipe comprising the steps of

• providing a run of pipe at a supply station,
• withdrawing pipe from said supply station and feeding it to a bending station remote from said supply station,
• bending a forward portion of said pipe at said bending station,
• varying the relative rates of said bending and withdrawing to decrease change in the length of pipe between said stations,
• said step of providing pipe comprising forming a long length of pipe and storing such pipe at said supply station,
• said steps of forming and storing comprising joining a plurality of pipe sections in end to end relation to form said long length, and coiling said long length upon a supply drum,
• filling at least a portion of the pipe on said supply drum with a solidifiable material, and
• solidifying said material within said pipe before the pipe is bent.

Apparatus for bending pipe comprising

• a bending station including a bending head for bending pipe,
• a feeding station including means thereon for feeding pipe to said bending head at the bending station,
• means for operating the bending head to bend the pipe and simultaneously pull pipe from the feeding station, and
• means for controlling the relative rates of feeding the pipe from the feeding station and bending the pipe to control the pull exerted by the bending upon the pipe.