A method for drawing and forming metal pipes

Abstract

The invention relates to a method for expanding and drawing a metal pipe, which includes: grinding the surface of the pipe, pickling with a mixed acid solution after the polishing, washing with water after pickling, and removing the remaining residue on the pipe. Mix acid, dry after washing; heat-treat one end of the pipe to be expanded, and then simply expand it in a hot state to make its diameter larger than the maximum diameter of the expanding mold, so that the expanding mold can enter the pipe smoothly Inside: Stretch oil into the pipe to form a protective oil film on the inner wall of the pipe to reduce the friction between the expanding die and the inner wall; put the pipe through the guide device and the sizing device on the machine tool.

Description

technical field

[0001] The invention relates to a forming method for diameter-expanding and drawing of metal pipes, which belongs to the field of plastic processing and forming. Background technique

[0002] Drawing processing is one of the important production methods of pipes and wires. It is a plastic forming method for forming parts by changing the cross section of pipes and wires. The products using the drawing process have good surface quality and precise dimensions, and can also improve the mechanical properties of the products, which has advantages that other plastic forming does not have.

[0003] Expanding drawing is a drawing method that draws a smaller diameter tube blank into a larger diameter tube blank. Expanding drawing is usually used to produce thin-walled tubing with smaller sections. In the traditional drawing process, the radius of the pipe becomes larger, the wall thickness is thinner, and the length is shortened. In the drawing process, it mainly exp...

Examples

Embodiment 1

[0032] The first step is to polish the surface of the stainless steel tube. After the grinding is completed, use the prepared mixed acid solution for pickling treatment. After pickling, wash with water to remove the residual mixed acid on the stainless steel tube. Dry after washing;

[0033] In the second step, one end of the stainless steel tube is heat-treated, and the diameter is simply expanded in a hot state, so that the diameter of the stainless steel tube is larger than the maximum diameter of the expanding die, so that the expanding die can smoothly enter the interior of the stainless steel tube;

[0034] The third step is to inject stretching oil into the stainless steel pipe;

[0035] The fourth step is to place the stainless steel pipe on the machine tool through the guide device and the sizing device;

[0036] The fifth step is to pass the core rod through the stainless steel tube. The front end of the core rod is equipped with a detachable expanding die, and the r...

Embodiment 2

[0046] The first step is to polish the surface of the GH4169 tube. After the grinding is completed, use the prepared mixed acid solution for pickling treatment. After pickling, wash with water to remove the residual mixed acid on the GH4169 tube. After washing, dry it;

[0047] In the second step, one end of the GH4169 tube is heat treated, and the diameter is simply expanded in a hot state, so that the diameter of the GH4169 tube is larger than the maximum diameter of the expanding die, so that the expanding die can smoothly enter the inside of the GH4169 tube;

[0048] The third step is to introduce stretching oil into the GH4169 pipe;

[0049] The fourth step is to place the GH4169 pipe on the machine tool through the guide device and the sizing device;

[0050] The fifth step is to pass the core rod through the GH4169 tube. The front end of the core rod is equipped with a detachable expansion die, and the rear end of the core rod is connected to the drawing machine;

[00...

technical field

[0001] The invention relates to a forming method for diameter-expanding and drawing of metal pipes, which belongs to the field of plastic processing and forming. Background technique

[0002] Drawing processing is one of the important production methods of pipes and wires. It is a plastic forming method for forming parts by changing the cross section of pipes and wires. The products using the drawing process have good surface quality and precise dimensions, and can also improve the mechanical properties of the products, which has advantages that other plastic forming does not have.

[0003] Expanding drawing is a drawing method that draws a smaller diameter tube blank into a larger diameter tube blank. Expanding drawing is usually used to produce thin-walled tubing with smaller sections. In the traditional drawing process, the radius of the pipe becomes larger, the wall thickness is thinner, and the length is shortened. In the drawing process, it mainly exp...

Examples

Embodiment 1

[0032] The first step is to polish the surface of the stainless steel tube. After the grinding is completed, use the prepared mixed acid solution for pickling treatment. After pickling, wash with water to remove the residual mixed acid on the stainless steel tube. Dry after washing;

[0033] In the second step, one end of the stainless steel tube is heat-treated, and the diameter is simply expanded in a hot state, so that the diameter of the stainless steel tube is larger than the maximum diameter of the expanding die, so that the expanding die can smoothly enter the interior of the stainless steel tube;

[0034] The third step is to inject stretching oil into the stainless steel pipe;

[0035] The fourth step is to place the stainless steel pipe on the machine tool through the guide device and the sizing device;

[0036] The fifth step is to pass the core rod through the stainless steel tube. The front end of the core rod is equipped with a detachable expanding die, and the r...

Embodiment 2

[0046] The first step is to polish the surface of the GH4169 tube. After the grinding is completed, use the prepared mixed acid solution for pickling treatment. After pickling, wash with water to remove the residual mixed acid on the GH4169 tube. After washing, dry it;

[0047] In the second step, one end of the GH4169 tube is heat treated, and the diameter is simply expanded in a hot state, so that the diameter of the GH4169 tube is larger than the maximum diameter of the expanding die, so that the expanding die can smoothly enter the inside of the GH4169 tube;

[0048] The third step is to introduce stretching oil into the GH4169 pipe;

[0049] The fourth step is to place the GH4169 pipe on the machine tool through the guide device and the sizing device;

[0050] The fifth step is to pass the core rod through the GH4169 tube. The front end of the core rod is equipped with a detachable expansion die, and the rear end of the core rod is connected to the drawing machine;

[00...

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