Method and device for bending pipe

Patent metadata

Field	Value
Publication number	US-10953448-B2
Application number	US-201615566479-A
Country	US
Kind code	B2
Filing date	Apr 25, 2016
Priority date	Jun 12, 2015
Publication date	Mar 23, 2021
Grant date	Mar 23, 2021

Abstract

A method for bending a pipe by, while sandwiching one portion of the pipe by a gripping device, sandwiching the other portion of the pipe between a pair of bending rolls and by causing the other bending roll to relatively revolve about one bending roll out of the pair of bending rolls, wherein the bending rolls are held by a common movable frame body, the relative revolution is realized by synchronous movement in which rotating movement for rotating the frame body and lateral movement for moving the frame body in a direction (Y-axis direction) perpendicular to a longitudinal direction (X-axis direction) of the pipe are synchronized with each other, and the movement in the Y-axis direction of the frame body is performed such that a position in the Y-axis direction of a center axis of the one bending roll is held and a position in the X-axis direction of a rotating center point of the rotating movement remains same.

First claim

The invention claimed is:

1. A method for bending a pipe, the method comprising:
sandwiching a first portion of the pipe by a gripping device,
sandwiching a second portion of the pipe at a rotating center point of a frame body, the frame body including first and second bending rolls, each of the first and the second bending rolls having a center axis fastened to the frame body and a rim with a groove, the second portion of the pipe being sandwiched between the first and second bending rolls at a contact point corresponding to the rotating center point of the frame body, and
bending the pipe by a synchronous movement including rotating the frame body about the rotating center point of the frame body while concurrently moving the frame body in a lateral direction (Y-axis direction) which is perpendicular to a longitudinal direction (X-axis direction) of the pipe, thereby causing the second bending roll to rotate about the center axis of the first bending roll,
wherein before the bending, the rotating center point of the frame body and the center axis of the first bending roll each have an initial X-axis position in the X-axis direction and an initial Y-axis position in the Y-axis direction, and
wherein the bending by the synchronous movement is performed without moving the initial Y-axis position of the center axis of the first bending roll and without moving the initial X-axis position of the rotating center point of the frame body.

2. The method for bending the pipe according to claim 1 , wherein after the bending step of bending the pipe,
adjusting a rotating angle by opening one or both of the first bending roll and the second bending roll of the pair of bending rolls, and
setting the frame body at a position of a desired rotating angle for rotating the frame body and laterally moving the frame body in the Y-axis direction differently from that used in the bending step.

3. The method for bending the pipe according to claim 2 , further comprising a feeding step of feeding the pipe by a desired length after the bending step,
wherein the bending step and the feeding step are repeatedly performed in a desired order.

4. The method for bending the pipe according to claim 2 , wherein the gripping device includes a rotating device that rotates the pipe about an axis of the pipe, and the method further comprises a step of using the rotating device to rotate the pipe about the axis thereof, wherein the adjusting the rotating angle step comprises adjusting a position in the Y-axis direction of the frame body and rotating the frame body, such that a direction of a line connecting center axes of both of the bending rolls to each other is oriented in the Y-axis direction, wherein the bending step, the adjusting the rotating angle step and the step of using the rotating device are repeatedly performed in a desired order.

5. A method for bending a pipe, the method-comprising:
sandwiching a first portion of the pipe by a gripping device,
sandwiching a second portion of the pipe between a pair of bending rolls mounted on a frame body at a rotating center point of the frame body, the second portion of the pipe including a contact point corresponding to the rotating center point of the frame body, the pair of bending rolls including a first bending roll and a second bending roll, each bending roll having a center axis and a rim with a groove, and
bending the pipe by a synchronous movement including rotating the frame body about the rotating center point of the frame body while moving the frame body in a lateral direction (Y-axis direction) which is perpendicular to a longitudinal direction (X-axis direction) of the pipe, thereby causing the second bending roll to revolve about and relative to the first bending roll,
wherein before the bending, the rotating center point of the frame body and the center axis of the first bending roll each have an initial X-axis position in the X-axis direction and an initial Y-axis position in the Y-axis direction,
wherein the bending by the synchronous movement is performed without moving the initial Y-axis position of the center axis of the first bending roll and without moving the initial X-axis position of the rotating center point of the frame body, and
wherein the gripping device includes a feeding device, and the method includes:
feeding the pipe by a length equal to ΔL using the feeding device,
wherein Δ L =[ R (θ−sin θ)]= Rθ−R sin θ, and

R sin θ is a length obtained by multiplying a radius R of the first bending roll by a sine value sin θ of a rotating angle θ (circular method) of the frame body, and
Rθ is a length obtained by multiplying the rotating angle θ by the radius R in the synchronous movement of the frame body.

6. An apparatus for bending pipe, comprising:
a gripping device configured to sandwich one portion of a pipe to be bent;
a frame body including a pair of bending rolls including first and second bending rolls, the first and second bending rolls each having a center axis fastened to the frame body and a groove extending in a circumferential direction around each bending roll, the pair of bending rolls being configured to sandwich another portion of the pipe to be bent between the first and second bending rolls at a rotating center point of the frame body;
a frame body moving device attached to the frame body and configured to move the frame body in a direction (Y-axis direction) that is perpendicular to a longitudinal direction (X-axis direction) of the pipe to be bent;
a frame body rotating device attached to the frame body and configured to rotate the frame body with respect to the frame body moving device; and
the frame body in combination with the frame body moving device and the frame body rotating device being configured to bend the pipe to be bent by causing the second bending roll to revolve relative to the first bending roll and about the first bending roll,
wherein the frame body moving device includes a controller configured to control the frame body rotating device and the frame body moving device so that the second bending roll fastened to the frame body revolves around the center axis of the first bending roll and bends the pipe to be bent in the circumferential direction around the first bending roll,
wherein the rotating center point of the frame body and the center axis of the first bending roll each have an initial X-axis position in the X-axis direction and an initial Y-axis position in the Y-axis direction, and
wherein the controller is configured to rotate and simultaneously to laterally move the frame body in the Y-axis direction without changing the initial X-axis position of the rotating center point of the frame body and without changing the initial Y-axis position of the center axis of the first bending roll.

7. The apparatus for bending pipe according to claim 6 , wherein
the gripping device includes a feeding device and a rotating device that rotates the pipe to be bent about an axis thereof, and
the controller is configured to control a feeding amount of the pipe to be bent by the feeding device and to control a rotating amount of the rotating device.

Assignees

• Sanoh Ind Co Ltd

Inventors

• Lan Guang Ping

Classifications

• B21D7/16

  Auxiliary equipment, e.g. for heating or cooling of bends · CPC title

• B21D7/024 Primary

  by a swinging forming member · CPC title

• B21D7/12

  with program control · CPC title

• B21D7/14

  combined with measuring of bends or lengths · CPC title