JPS60141329A - Method of wall-thickness increasing work - Google Patents

Abstract

PURPOSE:To increase and drcrease locally the outer and inner diameters of a blank material into prescribed dimensions by changing the relative speeds of clamps located at both sides of a locally heating device and a drawing die, through which the blank material such as a rod material or a pipe material passes. CONSTITUTION:A rod material or a pipe material 2, which passes through a locally heating device 1 and a drawing die 9, is clamped at its both sides by clamping devices 5, 8. The diameter of a locally heated material 2 is increased into a large prescribed diameter by drawing the material 2 with the aid of the die 9, by making the stretch-advancing speed v1 of the clamp 8 driven by a cylinder 7 higher than the pushing-in speed v2 of the clamp 5 driven by a cylinder 4. The pipe material 2 can also be formed into a pipe having prescribed outer diameter and prescribed small inner diameter by setting properly the speed difference between v1 and v2 and the diameter of die 9.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for increasing the wall thickness of a rod-shaped or tubular workpiece, and allows the outer shape of the workpiece to be freely changed after processing.

Conventional thickening processing equipment for rod-shaped or tubular workpieces is
The configuration is as shown in FIG. Reference numeral 1 denotes a local heating device as a heating means having a heating source such as a high frequency heating coil or a gas burner, and a pipe 2, which is a long workpiece, is inserted into the central toilet. The part facing 1 is locally heated. This local heating device 1
A cooling device 3 is provided adjacent to the. Similarly, the cooling device 3 has a ring shape through which the tube 2 is inserted into the central cavity.
A large number of coolant jet ports 3a are provided on the inner circumferential surface of the pipe 2, facing the pipe 2.
is drilled through which coolant is injected into the tube 2. Further, the local heating device 1 and the cooling device 3 are both supported so as to be movable in the axial direction of the tube 2 at the same speed. Furthermore, a pressurizing device 4 having a hydraulic or screw feed type driving source is provided between the local heating device 1 and the cooling device 3.
A clamping device 5 and a fixing device jt6 are provided, and one side of the tube 2 inserted into the central cavity of the local heating device 1 and the cooling device jt, 3 is fixed with the fixing device 6, and the other side is fixed. is gripped by a clamping device 5, and the tube 2 is pressed in the axial direction by a pressure device 4 via a sifting lamp device 5 toward a fixing device 6.

In this processing method, the local heating device 1 is activated, and the cooling device 3 is also activated at the same time to spread coolant so that the heating does not affect other parts, so that the temperature of the heated part of the tube 2 is balanced. After this condition is reached, the pressure device 4 is activated to press the tube 2 at a constant shrugging speed, and the tube 2 is thickened in the heating section. To do this continuously, the local heating device 1 is moved in the axial direction of the tube 2 at a speed V, and the cooling device jf
3 at the same speed V to cool the processed part.

However, since this method increases the diameter by an amount of 0w2, it is impossible to increase the wall thickness toward the inner diameter while leaving the outer diameter unchanged. Also, when processing pipes and rods to increase their thickness,
Nor was it possible to freely select the outer shape.

The present invention has been made in view of the above-mentioned circumstances, and its purpose is to enable the external shape of workpieces to be freely changed after processing in a method for increasing the thickness of workpieces such as H and rods. purpose.

The structure of the present invention that achieves the above object is a method for increasing the thickness of a rod-shaped or tubular workpiece by heating the circumference of the workpiece with a heating means and moving the heating section in the longitudinal direction of the workpiece. The present invention is characterized in that a forming tool is provided at the rear of the means, and the processed portion after the thickness increasing process is processed by the forming tool.

Hereinafter, the wall thickness increasing processing method according to the present invention will be explained in detail based on an embodiment shown in the drawings.

The apparatus used to carry out the method of the present invention has a general construction similar to that of the conventional apparatus, as shown in FIGS. 2-3.

1 is a local heating device, 4 is a thickness increasing pressure device, 5 is its clamping device, and furthermore, a drive source such as a hydraulic type or a screw feeder is installed on the extension of the thickness increasing pressure device 4. A pressure device 7 for drawing is provided, and a clamp device 8 is provided at the tip of the telescoping rod to grip the tube 2, which is the workpiece.
Immediately after the local heating device 1, a forming tool 9 such as a die or a roller for straightening the outer diameter is provided.

Next, the operation of increasing the thickness of a pipe using the above-mentioned apparatus will be explained.

First, the pipe 2 is gripped by the clamping device 8 for drawing and the clamping device 5 for thickening, and the pressure device 7 for drawing and the pressurizing device 4 for thickening are operated in the same direction, and 'i''2 is set at the speed V1. Next, the local heating device 1 is activated to heat the moving tube 2, and after the temperature of the heated part reaches a steady state,
What is the speed of the pressurizing device 4 for thickening? Increase to 2. Due to this action, the locally heated portion of the tube 2 is shrunk at a shrugging speed of (22-m), and its thickness and diameter are increased.

The shrunken locally heated portion of the tube 2 advances at a speed, enters the forming tool 9, and is processed into the outer shape of the squeegee while exiting. By doing this operation continuously, you can get relief.

As shown in FIG. 3, it is possible to increase the diameter and thickness of the tube 2 (increasing the thickness toward the inner diameter side is also possible) at any position and length of the tube 2. After processing the required length, use the local heating device fl
, and change the speed of the thickening pressurizing device 4? Lower the IK and finish the machining work. The forming tool 9 is not limited to one having a circular cross section, but may also be of an irregular shape to produce an irregularly shaped tube or the like. Further, the workpiece may be a rod-shaped solid material, which is processed in the same manner as described above.

As described above in detail based on the embodiments.

According to the wall thickness increasing processing method according to the present invention, by providing a forming tool, it is possible to obtain an arbitrary external shape, and when processing a pipe, it is possible to increase the wall thickness on the inside. . Furthermore, the above-mentioned processing is possible at any position and length of a rod-shaped or tubular workpiece.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a conventional wall thickness increasing processing apparatus, and FIGS. 2 and 3 are process diagrams of an embodiment of the wall thickness increasing processing method according to the present invention. In the drawings, 1 is a local heating device, 2 is a tube, 3 is a cooling device, and 4 is a thickening pressurizing device. 5 is a clamping device for thickening, 7 is a pressure device for drawing, 8 is a clamping device for drawing, and 9 is a forming tool. Continued from page 1 0 Inventor: Tomoki Kawanami, Nagasaki Heavy Artillery, Nagasaki Heavy Artillery, Uramachi 0 Inventor: Masayuki Moriyama, Nagasaki Heavy Artillery, Uramomachi

Claims (1)

[Claims] In a method of increasing the thickness of a rod-shaped or tubular workpiece by heating it with a rotary heating means and moving the heating part in the longitudinal direction of the workpiece, a forming tool is provided immediately after the heating means, A processing method for increasing wall thickness, characterized in that the processed portion after the processing for increasing wall thickness is processed by the forming tool.