CN211707741U

CN211707741U - Drawing die for pipes with rectangular cross sections and unequal wall thicknesses

Info

Publication number: CN211707741U
Application number: CN201922153122.5U
Authority: CN
Inventors: 钱小兵
Original assignee: Taizhou Zhicheng Cemented Carbide Mould Co ltd
Current assignee: Taizhou Zhicheng Cemented Carbide Mould Co ltd
Priority date: 2019-11-29
Filing date: 2019-12-05
Publication date: 2020-10-20
Anticipated expiration: 2029-12-05

Abstract

The utility model discloses a tensile mould of wall thickness tubular product that varies of rectangular cross section, including transition external mold, shaping external mold, the core head that moves about divide into transition end, extrusion end, shaping end. In the process of controlling the stretching of the pipe, the drawn pipe is in close contact with the transition outer die, the inner wall of the forming outer die and the moving core print, so that the inner surface and the outer surface of the drawn pipe are clean and consistent, and the parameter values of the upper wall thickness, the lower wall thickness, the left wall thickness and the right wall thickness of the pipe and the R values of four right-angled fillets on the inner wall of the pipe can be adjusted according to the parameter setting on the moving core print.

Description

Drawing die for pipes with rectangular cross sections and unequal wall thicknesses

Technical Field

The utility model relates to a mechanical tubes area trip core dish draws the field, especially relates to a tensile mould of wall thickness copper pipe that rectangle cross-section varies.

Background

In view of the fact that the rectangular copper pipe in China at present adopts two methods of straight pulling and air pulling (coil pulling). The straight pulling has the defects that the length of the copper pipe is limited to a certain extent (within 10 meters), the air pulling has the defects that the length problem is solved, but the size, the size and the wall thickness of an inner hole R cannot be controlled and stabilized, and the copper pipe with the same wall thickness as the air pulling can only be used for pulling the copper pipe with the same wall thickness and cannot be pulled with the copper pipe with the different wall thickness. The method provided by the patent of 'moving core ball stretching combined die (patent number: CN 201821036680.2)' effectively avoids the collapse and the concavity of the inner cavity of the copper pipe in the stretching process, ensures uniform transition deformation and consistent wall thickness and outer diameter change of the pipe, and theoretically realizes infinite length of the copper pipe stretched by the stretching combined die. However, the patent does not solve the processing problem of the pipe with the rectangular section with unequal wall thickness. (for example: two opposite sides of a rectangular copper tube have different wall thicknesses, the dimensions of the two opposite sides are respectively 1.8mm on one side and 1.0mm on the other side.)

In the refrigeration industry and the medical appliance industry at present, the requirements on the sizes of various copper pipes are higher and higher, and particularly in the medical appliance industry, the requirements on the copper pipes with different wall thicknesses are higher and higher, and the requirements on the size specifications are higher and higher.

The prior method for processing the copper pipe with the rectangular section and unequal wall thickness is usually formed by welding and combining two copper plates with different wall thicknesses. However, the above methods all stay in the state of manual operation, which not only wastes manpower resources seriously, but also can not ensure the precision and strength of the copper tube, and can not meet the requirements of the medical appliance industry for high quality and high performance. At present, most of domestic copper pipes are used by means of imports, so that the lack of high-quality and high-precision copper pipes with rectangular sections with unequal wall thicknesses is a common problem in the medical instrument industry in China.

SUMMERY OF THE UTILITY MODEL

The utility model discloses the technical problem who solves has overcome prior art's not enough, provides a wall thickness copper pipe drawing die that varies of rectangular cross section, in order to solve above-mentioned technical problem, the utility model discloses a technical scheme as follows: the utility model discloses a transition external mold, the shaping external mold, the core head moves about, the center of transition external mold is equipped with first trapezoidal form compression hole and the rectangle compression hole one of arc curved surface and is connected, the center of shaping external mold is equipped with second trapezoidal form compression hole and rectangle compression hole two-phase connection, second trapezoidal form compression hole inside is equipped with the core head that moves about, the core head that moves about divide into the transition end, the extrusion end, the shaping end, transition end and shaping end are the cuboid shape, middle extrusion end is the trapezoidal form, extrusion end trapezoidal form reduces to tensile direction gradually, the contained angle on two opposite sides in the second trapezoidal form compression hole of shaping external mold is 9-30, a pair of inclined plane contained angle that extrusion end trapezoidal form is greater than another pair of inclined plane contained angle, 4 edges that extrusion end trapezoidal form is the fillet.

Furthermore, the included angle of one pair of inclined planes of the extrusion end step platforms is 0.5-5 degrees larger than that of the other pair of inclined planes.

Furthermore, the fillet is conical, and the radius gradually decreases towards the stretching direction.

Further, the molding outer die is multiple.

The utility model has the advantages as follows:

1. the defects of the traditional straight pulling and the traditional coiling pulling are thoroughly overcome, and the requirements on various sizes of copper tube products with rectangular sections and unequal wall thicknesses are controlled by adjusting the angle matching of the outer die and the moving core head within a certain numerical range while the strength of the copper tube is ensured.

2. The copper pipe enterprise is helped to improve the working efficiency by about 80%.

3. The labor cost of the enterprise is reduced by 80-90%, and the profit of the copper pipe enterprise can be improved by 50-80%.

Drawings

FIG. 1 is a front view of the transition outer mold of the present invention;

FIG. 2 is a sectional view of the transition outer mold of the present invention;

FIG. 3 is a front view of the forming outer mold of the present invention;

FIG. 4 is a sectional view of the outer mold of the present invention;

FIG. 5 is a front view of the floating core head of the present invention;

FIG. 6 is a left side view of the floating core head of the present invention

FIG. 7 is a top view of the floating core head of the present invention

FIG. 8 is a partial enlarged view of the floating core of the present invention;

FIG. 9 is a schematic diagram of the drawing die for copper tubes with different wall thicknesses and rectangular cross sections according to the present invention;

reference numbers in the figures: 1-transition external mold; 2-forming an external mold; 3-a traveling core print; 4-copper pipe; 11-a first trapezoidal compression hole of an arc-shaped curved surface; 12-a rectangular compression hole I; 21-a second trapezoidal compression hole, 22-a second rectangular compression hole; 31-transition end; 32-extrusion end; 33-forming end; 34-round corner.

Detailed Description

To facilitate understanding and practice of the invention by those of ordinary skill in the art, the invention is described in further detail below with reference to the accompanying drawings and detailed description, for example: customers require to process rectangular special pipes with different wall thicknesses, wherein the length of a copper pipe is 200 meters, the inner hole R0.5mm, the outer circle R1.5mm, the left wall thickness and the right wall thickness are 1.8mm, and the upper wall thickness and the lower wall thickness are 1.0mm, and the embodiment adopts 4 procedures of forming the outer mold 2.

As shown in figures 1-8, the first process adopts a copper pipe 4 with the wall thickness of 1.4mm to control the basic forming of the copper pipe by coiling and drawing through a transition external die 1, so that the copper pipe becomes a pipe with an approximate rectangular section.

As shown in fig. 9, in the second process, the copper tube 4 with an approximately rectangular cross section is adopted, and the size and the wall thickness of the tube with the rectangular cross section are adjusted by coiling and drawing the forming outer die 2 and the moving core head 3, the included angle between two opposite sides of the second trapezoidal compression hole 21 of the forming outer die 2 is 9-30 degrees, the included angle between the upper side and the lower side of the trapezoidal shape of the extrusion end 32 of the moving core head 3 is 9-28 degrees, and the included angle between the left side and the right side is 12-30 degrees. The wall thickness of the copper tube 4 is 1.4mm, the wall thickness of the copper tube 4 is adjusted up, down, left and right through the size and angle of the moving core head and the radius R value of 4 edge fillets 34 of the extrusion end 32 step table, the wall thickness of the copper tube 4 is reduced to 1.35m, and the wall thickness of the copper tube 4 is increased by 0.04mm-0.06 mm.

And in the third procedure, the same method as in the second procedure is repeatedly adopted, the left and right wall thickness of the copper pipe 4 is increased by 0.05mm-0.08mm, and the upper and lower wall thickness of the copper pipe 4 is reduced to 1.2 m.

The fourth procedure adopts the same method of the third procedure repeatedly, the left and right wall thickness of the copper tube 4 is increased to 1.65mm, and the upper and lower wall thickness of the copper tube 4 is reduced to 1.1 mm.

The fifth procedure adopts the same method of the fourth procedure repeatedly, the left and right wall thickness of the copper tube 4 is increased to 1.78-1.82mm, and the upper and lower wall thickness of the copper tube 4 is reduced to 1.0-1.05 mm.

The more the number of repetitions, the higher the precision of the product and the greater the strength.

The moving core print 3 is made of hard alloy die steel.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of improvements and decorations can be made without departing from the concept of the present invention, and these improvements and decorations should also be considered as the protection scope of the present invention.

Claims

1. A drawing die for a pipe with a rectangular cross section and unequal wall thickness comprises a transition outer die (1), a forming outer die (2) and a moving core head (3), wherein a first trapezoidal compression hole (11) with an arc-shaped curved surface is formed in the center of the transition outer die (1) and is connected with a first rectangular compression hole (12), a second trapezoidal compression hole (21) is formed in the center of the forming outer die (2) and is connected with a second rectangular compression hole (22), the moving core head (3) is arranged inside the second trapezoidal compression hole (21), the moving core head (3) is divided into a transition end (31), an extrusion end (32) and a forming end (33), the transition end (31) and the forming end (33) are cuboid, the middle extrusion end (32) is trapezoidal, and the trapezoidal shape of the extrusion end (32) is gradually reduced towards the drawing direction,

the method is characterized in that: the included angle of two opposite sides of a second trapezoidal table-shaped compression hole (21) of the forming outer die (2) is 9-30 degrees, the included angle of one pair of inclined planes of the ladder table of the extrusion end (32) is larger than that of the other pair of inclined planes, and 4 edges of the ladder table of the extrusion end (32) are fillets (34).

2. The drawing die for the pipe with the rectangular section and the unequal wall thickness as claimed in claim 1, is characterized in that: the included angle of one pair of inclined planes of the extrusion end (32) step is 0.5-5 degrees larger than that of the other pair of inclined planes.

3. The drawing die for the pipe with the rectangular section and the unequal wall thickness as claimed in claim 1, is characterized in that: the fillet (34) is conical and gradually reduces in radius in the drawing direction.

4. A drawing die for pipes with different wall thicknesses and rectangular sections as claimed in any one of claims 1 to 3, wherein: the molding outer die (2) is multiple.