CN107931550B

CN107931550B - Graphite die for drawing copper and copper alloy pipes

Info

Publication number: CN107931550B
Application number: CN201711254073.3A
Authority: CN
Inventors: 杜小秋; 王光辉; 阮学松; 郭锋
Original assignee: Zhejiang Tongcheng Alloy Copper Pipe Co ltd
Current assignee: Zhejiang Tongcheng Alloy Copper Pipe Co ltd
Priority date: 2017-12-03
Filing date: 2017-12-03
Publication date: 2022-03-22
Anticipated expiration: 2037-12-03
Also published as: CN107931550A

Abstract

The invention relates to a graphite mould for drawing copper and copper alloy pipes, wherein a mould core is arranged inside an outer mould, and one side of the mould core is fixed by a plurality of pins; the other side of the mold core is divided into 3 sections with the diameters of 48-52 mm, 40-45 mm and 37-41 mm, and the three sections are connected with each other to form a conical structure. The outer mold, the mold core and the pins are all prepared by extrusion molding of high-purity graphite. In the invention, the original mold core taper is changed, the mold core with the traditional mold with the total length of 400mm is divided into 3 sections, the diameters of the mold core are respectively 48-52 mm, 40-45 mm and 37-41 mm, a conical state is formed, the vortex shape is controlled to be minimum, the hand feeling is small, the black line in the tube blank is eliminated after the subsequent rolling-stretching, and the effect is obvious.

Description

Graphite die for drawing copper and copper alloy pipes

Technical Field

The invention relates to a graphite die for drawing copper and copper alloy pipes, belonging to the technical field of copper and copper alloy.

Background

In the production of copper and copper alloy pipes, the copper liquid needs to be drawn and stretched so as to produce a proper pipe blank. In actual use, the inner wall of a copper ingot pulled by the traditional graphite die generates spiral lines, and the hand feeling is strong. The finished pipe blank produced by the working procedures of rolling, stretching and the like turns the spiral grains (stretching) with hand feeling into obvious 'black lines' defects. The black line exists on the inner wall of the tube blank, the attractiveness is affected, and the quality hidden danger (such as flaring cracking, tube breakage in a pressure test and the like) exists on the next production process (such as pipe necking, flaring, tube bending and the like).

Disclosure of Invention

The invention aims to provide a graphite die for drawing copper and copper alloy pipes, so as to better improve the drawing treatment effect of the copper and copper alloy pipes.

In order to achieve the above object, the present invention has the following technical means.

A graphite mould for drawing copper and copper alloy pipes is characterized in that a mould core is arranged inside an outer mould, and one side of the mould core is fixed by a plurality of pins; the other side of the mold core is divided into 3 sections with the diameters of 48-52 mm, 40-45 mm and 37-41 mm, and the three sections are connected with each other to form a conical structure.

Furthermore, the outer die, the die core and the pin are all prepared by extrusion molding of high-purity graphite.

The graphite mold is used in a casting working section and is mainly used for continuously casting phi 92 x 25mm copper ingots, and the copper ingots are formed and pulled through the graphite mold and other accessories by a pulling servo motor at a pulling speed of 170-380 mm per minute. When the graphite mold is used, the graphite mold is arranged on a crystallizer panel through a cooling copper sleeve, is tightly matched with four-hole bricks of a casting furnace and is locked through a locking screw arranged on a furnace body of the casting furnace; and when the temperature of the copper water in the casting furnace reaches the traction requirement, starting a traction machine for traction, wherein the copper water flows in through 4 phi 8 small holes distributed on the graphite mold to generate vortex, and the copper ingot is pulled out through one-time water cooling molding.

The invention has the beneficial effects that: in the invention, the original mold core taper is changed, the mold core with the traditional mold with the total length of 400mm is divided into 3 sections, the diameters of the mold core are respectively 48-52 mm, 40-45 mm and 37-41 mm, a conical state is formed, the vortex shape is controlled to be minimum, the hand feeling is small, the black line in the tube blank is eliminated after the subsequent rolling-stretching, and the effect is obvious.

Drawings

FIG. 1 is a schematic structural view of a graphite mold used in the examples of the present invention.

FIG. 2 is a schematic sectional view of a graphite mold A-A used in the examples of the present invention.

Fig. 3 is a schematic view of the structure of the pin in the graphite mold used in the example of the present invention.

Detailed Description

The following description of specific embodiments of the present invention is provided in connection with examples to facilitate a better understanding of the present invention.

Examples

As shown in fig. 1, 2 and 3, the graphite die for drawing the copper and alloy pipes is characterized in that a die core 1 is arranged in an outer die 3, and one side of the die core 1 is fixed by a plurality of pins 2; the other side of the mold core 1 is divided into 3 sections with the diameters of 48-52 mm, 40-45 mm and 37-41 mm, and the three sections are connected with each other to form a conical structure.

Furthermore, the outer die 3, the die core 1 and the pin 2 are all prepared by extrusion molding of high-purity graphite.

In actual use, the inner wall of a copper ingot pulled by the traditional graphite die generates spiral lines, and the hand feeling is strong. The finished pipe blank produced by the working procedures of rolling, stretching and the like turns the spiral grains (stretching) with hand feeling into obvious 'black lines' defects. The black line exists on the inner wall of the tube blank, the attractiveness is affected, and the quality hidden danger (such as flaring cracking, tube breakage in a pressure test and the like) exists on the next production process (such as pipe necking, flaring, tube bending and the like).

In the invention, the original mold core taper is changed, the mold core with the traditional mold with the total length of 400mm is divided into 3 sections, the diameters of the mold core are respectively 48-52 mm, 40-45 mm and 37-41 mm, a conical state is formed, the vortex shape is controlled to be minimum, the hand feeling is small, the black line in the tube blank is eliminated after the subsequent rolling-stretching, and the effect is obvious.

While the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention.

Claims

1. A graphite mould for drawing copper and copper alloy pipes is characterized in that a mould core is arranged inside an outer mould, and one side of the mould core is fixed by a plurality of pins; the method is characterized in that: the other side of the mold core is divided into 3 sections with the diameters of 48-52 mm, 40-45 mm and 37-41 mm respectively, and the three sections are connected with each other to form a conical structure; the outer mold, the mold core and the pin are all prepared by extrusion molding of high-purity graphite; the graphite mold is used in a casting working section and is used for continuously casting a phi 92 x 25mm copper ingot, and the copper ingot is subjected to molding traction through the graphite mold and other accessories and a traction servo motor according to the drawing speed regulated at 170-380 mm per minute; when the graphite mold is used, the graphite mold is arranged on a crystallizer panel through a cooling copper sleeve, is tightly matched with four-hole bricks of a casting furnace and is locked through a locking screw arranged on a furnace body of the casting furnace; and when the temperature of the copper water in the casting furnace reaches the traction requirement, starting a traction machine for traction, wherein the copper water flows in through 4 small holes with the diameter of 8mm distributed on the graphite mold to generate vortex, and the copper ingot is pulled out through one-time water cooling molding.