A pressing head die for square thin-walled pipes

Abstract

A punch die for square thin-walled pipes comprises an upper die, a lower die, and a guide plate. The upper die comprises an upper die plate, the lower end of which is provided with at least one set of spaced square cores and boss cores, with square grooves formed between the square cores and boss cores. The lower die comprises a lower die plate, the upper end of which is provided with at least one set of spaced square grooves and inverted concave grooves, with square protrusions formed between the square grooves and inverted concave grooves. The square core and boss core of the upper die plate are respectively inserted into the square groove and inverted concave groove of the lower die plate, and the square protrusion of the lower die plate is inserted into the square groove of the upper die plate. The lower die plate is connected to one end of the guide plate. The pipe end processed by the die of the present invention has a regular shape, is easy to pass through the die, is easy to clamp, and is smoothly drawn, effectively improving the drawing quality of the square pipe.

Description

Technical Field

[0001] The invention belongs to the technical field of pipe processing, and in particular relates to a pressing head die for square thin-walled pipes. Background Art

[0002] Square thin-walled tubes have the advantages of light weight, high rigidity, low cost and good energy absorption effect, and are widely used in rail transportation, energy, chemical industry, aerospace and other fields. Before drawing, the square thin-walled tube needs to be shrunken at the end of the tube billet so that the end of the tube billet can smoothly pass through the drawing die hole and obtain the tube diameter and wall thickness that meet the requirements of the tube process. At present, the commonly used square tube shrinking processes include rolling, rotary swaging and special tube shrinking equipment. The end of the thin-walled tube billet is plastically deformed by a rolling machine or a rotary swaging machine, and the cross-section of the end of the formed tube is approximately circular. This method has problems such as large equipment investment, large floor space, and noise pollution. In addition, the cross-section of the final tube end is approximately circular, and the traction clamp is unstable during drawing; special tube shrinking equipment requires additional equipment investment. Summary of the Invention

[0003] In view of the above-mentioned deficiencies in the prior art, the present invention provides a pressing head die for square thin-walled pipes.

[0004] The present invention is achieved through the following technical solutions.

[0005] A pressing head die for square thin-walled pipes, characterized in that the die comprises: an upper die (1), a lower die (2) and a guide plate (3); the upper die (1) comprises an upper die plate, the lower end of the upper die plate is provided with at least one group of spaced square cores (4) and boss cores (5), a square groove is formed between the square cores (4) and the boss cores (5); the lower die (2) comprises a lower die plate, the upper end of the lower die plate is provided with at least one group of spaced square grooves (6) and inverted concave grooves (7), a square protrusion (8) is formed between the square grooves (6) and the inverted concave grooves (7); the square cores (4) and boss cores (5) of the upper die plate are respectively inserted into the square grooves (6) and inverted concave grooves (7) of the lower die plate, and the square protrusion (8) of the lower die plate is inserted into the square groove of the upper die plate; the lower die plate is connected to one end of the guide plate (3).

[0006] Furthermore, the guide plate (3) comprises a square plate, the square plate is provided with a plurality of rows of positioning pin holes (9) or a plurality of parallel square grooves, positioning pins are inserted into the positioning pin holes (9), a feeding channel (10) is formed between every two rows of positioning pin holes, and the plurality of feeding channels (10) are respectively connected to the square groove (6) and the inverted concave groove (7) of the lower template; or the plurality of square grooves on the square plate are respectively connected to the square groove (6) and the inverted concave groove (7) of the lower template.

[0007] Furthermore, an elastic pad (11) is provided between the upper end of the square protrusion (8) of the lower template and the square groove of the upper template.

[0008] Furthermore, the raised portion of the boss-shaped core (5) is in the shape of an inverted trapezoid or has an arc-shaped side.

[0009] Furthermore, the raised portion of the inverted concave groove (7) is in the shape of an inverted trapezoid or the side thereof is in the shape of an arc.

[0010] Furthermore, the relationship between the distance H(x1) between the lower end of the boss-shaped core (5) of the upper mold plate and the inner bottom of the inverted concave groove (7) of the lower mold plate and the length L(a) of the longer side of the pressing head after the square thin-walled tube is finally formed is: H(x1)=0.80~0.95L(a).

[0011] Furthermore, the groove width M(x2) of the square groove (6) of the lower template is 1.05-1.2H(x1).

[0012] Furthermore, the relationship between the distance H(x2) between the lower end of the square core (4) of the upper template and the inner bottom of the square groove (6) of the lower template and the length L(b) of the shorter side of the pressing head after the square thin-walled tube is finally formed is: H(x2)=0.95~1.0L(b).

[0013] The beneficial technical effects of the present invention include providing a press die for square thin-walled pipes with a simple structure and low manufacturing cost. The processed pipe ends have regular shapes, are easy to pass through the die, easy to clamp, and draw smoothly, effectively improving the drawing quality of square pipes. Furthermore, the present invention can solve the problems of large investment and large floor space required by current square thin-walled pipe necking equipment or devices, effectively improving the on-site operating environment, facilitating production and manufacturing, and achieving market demand. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural schematic diagram of the present invention.

[0015] Figure 2 It is a top view of the present invention.

[0016] Figure 3 for Figure 2 AA section view.

[0017] Figure 4 for Figure 2 BB cross-sectional view. DETAILED DESCRIPTION

[0018] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0019] like Figure 1-4As shown, a pressing head mold for square thin-walled pipes includes: an upper mold 1, a lower mold 2 and a guide plate 3; the upper mold 1 includes an upper mold plate, and the lower end of the upper mold plate is provided with at least one group of spaced square cores 4 and boss cores 5, the raised part of the boss core 5 faces downward, and a square groove is formed between the square core 4 and the boss core 5; the lower mold 2 includes a lower mold plate, and the upper end of the lower mold plate is provided with at least one group of spaced square grooves 6 and inverted concave grooves 7, and a square protrusion 8 is formed between the square groove 6 and the inverted concave groove 7; the square core 4 and the boss core 5 of the upper mold plate are respectively inserted into the square groove 6 and the inverted concave groove 7 of the lower mold plate, and the square protrusion 8 of the lower mold plate is inserted into the square groove of the upper mold plate; the lower mold plate is connected to one end of the guide plate 3, which can be a threaded connection or a pressure plate fixation, and the guide plate 3 is used to cooperate with feeding.

[0020] Furthermore, the guide plate 3 includes a square plate, which is provided with multiple rows of positioning pin holes 9 (each row of positioning pin holes can be 2) or multiple parallel square grooves, the positioning pin holes 9 are cylindrical positioning pin holes or conical positioning pin holes, and positioning pins are inserted in the positioning pin holes 9. A feeding channel 10 is formed between every two rows of positioning pin holes, and multiple feeding channels 10 are respectively connected to the square groove 6 and the inverted concave groove 7 of the lower template; or the multiple square grooves on the square plate are respectively connected to the square groove 6 and the inverted concave groove 7 of the lower template.

[0021] An elastic pad 11 is provided between the upper end of the square protrusion 8 of the lower template and the square groove of the upper template.

[0022] The raised portion of the boss-shaped core 5 is an inverted trapezoidal shape or has curved sides, while the raised portion of the inverted concave groove 7 is also an inverted trapezoidal shape or has curved sides. This ensures an arc-shaped transition between the compressed and uncompressed areas of the tube, effectively preventing significant deformation or breakage of the tube and extending the service life of the mold. The raised portion can also have a curved surface structure.

[0023] The relationship between the distance H(x1) between the lower end of the boss-shaped core 5 of the upper template and the bottom of the inverted concave groove 7 of the lower template and the length L(a) of the longer side of the pressing head after the square thin-walled tube is finally formed is: H(x1) = 0.80~0.95L(a); ensuring that the size of the square tube after the first step of processing meets the process requirements and at the same time improving the service life of the mold.

[0024] The width of the square groove 6 of the lower template is M(x2) = 1.05-1.2H(x1). This ensures that after the square tube is processed in the first step, it can be smoothly processed in the second step after being turned 90 degrees, so that the final square tube size meets the process requirements.

[0025] The relationship between the distance H(x2) between the lower end of the square core 4 of the upper mold plate and the inner bottom of the square groove 6 of the lower mold plate and the length L(b) of the shorter side of the punch after the final forming of the square thin-walled tube is: H(x2) = 0.95-1.0L(b). This ensures that the dimensions of the square tube after the second step of processing meet the process requirements.

[0026] When using the ram die, a square thin-walled tubing is placed between the two rows of locating pin holes 9 or within the square grooves of the guide plate 3. The tubing is then inserted into the inverted concave groove 7 of the lower die plate. As the upper die 1 moves downward, the first ram process is performed on the end of the thin-walled tubing. After the upper die 1 completes its downward movement, it immediately moves upward, removes the tubing processed in the first step, flips it 90°, and places it between the other two rows of locating pin holes 9 or within the square grooves of the guide plate 9. The tubing is then inserted into the square groove 6 of the lower die plate. As the upper die 1 moves downward again, the second ram process is performed on the end of the tubing. After the upper die 1 completes its downward movement, it immediately moves upward, removes the tubing processed in the second step, and finally, the tubing is formed into the final ram-formed tubing.

[0027] The above description is only a preferred embodiment of the present invention and does not limit the invention. It should be noted that for those skilled in the art, under the technical enlightenment provided by the present invention, other equivalent improvements can be made, all of which can achieve the purpose of the present invention and should be considered as the scope of protection of the present invention.

Claims

1. A press head die for square thin-walled pipes, characterized in that: The mold comprises: an upper mold (1), a lower mold (2) and a guide plate (3); the upper mold (1) comprises an upper mold plate, the lower end of the upper mold plate is provided with at least one group of spaced square cores (4) and boss cores (5), the convex portion of the boss core (5) is inverted trapezoidal or has an arcuate side, and a square groove is formed between the square core (4) and the boss core (5); the lower mold (2) comprises a lower mold plate, the upper end of the lower mold plate is provided with at least one group of spaced square grooves (6) and inverted concave grooves (7), the convex portion of the inverted concave grooves (7) is inverted trapezoidal or has an arcuate side, and a square protrusion (8) is formed between the square grooves (6) and the inverted concave grooves (7); the square core (4) and boss core (5) of the upper mold plate are respectively inserted into the square grooves (6) and In the inverted concave groove (7), the square protrusion (8) of the lower template is inserted into the square groove of the upper template; the lower template is connected to one end of the guide plate (3); the relationship between the distance H (x1) between the lower end of the boss core (5) of the upper template and the inner bottom of the inverted concave groove (7) of the lower template and the length L (a) of the longer side of the pressure head after the square thin-walled tube is finally formed is: H (x1) = 0.80 ~ 0.95L (a); the groove width M (x2) of the square groove (6) of the lower template is 1.05-1.2H (x1); the relationship between the distance H (x2) between the lower end of the square core (4) of the upper template and the inner bottom of the square groove (6) of the lower template and the length L (b) of the shorter side of the pressure head after the square thin-walled tube is finally formed is: H (x2) = 0.95 ~ 1.0L (b).

2. The mold according to claim 1, characterized in that The guide plate (3) comprises a square plate, and the square plate is provided with multiple rows of positioning pin holes (9) or multiple parallel square grooves, positioning pins are inserted into the positioning pin holes (9), and a feeding channel (10) is formed between every two rows of positioning pin holes, and the multiple feeding channels (10) are respectively connected to the square groove (6) and the inverted concave groove (7) of the lower template; or the multiple square grooves on the square plate are respectively connected to the square groove (6) and the inverted concave groove (7) of the lower template.

3. The mold according to claim 1, characterized in that An elastic pad (11) is provided between the upper end of the square protrusion (8) of the lower template and the square groove of the upper template.

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