CN102836891A

CN102836891A - Technique for drawing and expanding metal tubes by cold drawing

Info

Publication number: CN102836891A
Application number: CN2011101673185A
Authority: CN
Inventors: 高玉树
Original assignee: Individual
Current assignee: Individual
Priority date: 2011-06-21
Filing date: 2011-06-21
Publication date: 2012-12-26

Abstract

The invention provides a technique for drawing and expanding metal tubes by cold drawing, comprising the following steps: sawing one end of a metal tube to be expanded to form 1-4 openings in the axial direction of the tube, letting the other end pass through a core bar, when the tube openings are exposed from the core bar, inserting the tube openings into a core print, fastening the core print, then crashing the metal tube into the end of the fixed core print to let the core print enter the root of the saw cut, clipping about 2/3 of the opening parts to a drawing clamp to draw, when sizing and expanding with an outer mold, making heads for the opening end and penetrating the outer mold to draw; when coil drawing, directly clipping the tapered core print to the root of the saw cut of the tube then making head and conducting coil drawing, and drawing by sizing and expanding with the core or outer mold for several times to obtain a required expanded diameter tube. According to the invention, large-scale production that small metal tubes change into large metal tubes is realized, and the technique disclosed herein is an efficient and low-cost technology of utilizing small tube blanks, small tubes to produce large tubes in processing tubes for enterprises.

Description

The process of cold-drawn stretching expanding metal tube

Technical field

The invention provides a kind of process of cold-drawn stretching expanding metal tube; Its technological process is: metal pipe material one end that will treat expanding along 1～4 (1～2 the best) direct-axis of all sawings of pipe to opening; With tubing not opening one end pierce into core bar; The tubing openend pierces into core print (threaded in this way core print directly is anchored on the core bar end and gets final product), fastening core print after exposing the core bar fastening end; The both hands metal tube of holding with a firm grip hits the first end of fixed core then; Make core bar, core print enter into the root of cuts or more inwards, directly open end about 2/3 parts are clipped on the drawing pincers and carry out drawing, must opening be passed with a system machine or artificial system head like band external mold sizing expanding and be clipped in drawing behind the external mold and clamp and carry out drawing; Directly the tapered core head-clamp is drawn at tubing cuts root back head hub disk during the drawing of plate drawing machine kind equipment, it is constant to obtain required pipe internal diameter after passing through the several belt carcass or adding the drawing of external mold sizing controlling dimension expanding, the wall thickness attenuation; Or external diameter is constant, the wall thickness attenuation; Or external diameter increases, the tubing of the size of wall thickness attenuation.The technology that the present invention adopted; Realized that the metal pipe material tubule becomes the large-scale production of bassoon; Be that enterprise reduces the efficient process that overstocks and make full use of little pipe, the big tubing of tubule material production in tubing processing; Be a kind of simple, efficient, low power consuming, processing technology cheaply, solved the shock processing method that tubule becomes bassoon fully.It is the once far-reaching change of tubing cold-drawn processing technology.

Background technology

The metal pipe material cold drawing is widely used a kind of technology in the fine finishining of metal current tubing, is the first-selection that the seamless metal pipe undergauge subtracts the wall finishing step, is the production technology that current domestic and international production metal pipe material uses at most; This technology all is to use the undergauge at metal pipe material to subtract wall or undergauge increases aspect the wall; Describe though subtract the technology that moulding is arranged on the wall drawing process in hole enlargement, it is few in actual production, using, and this mainly is to receive processing technology complicated; Be difficult to apply in the production; Due to more can not accomplishing scale production, this process has realized the hole enlargement production of the simplification of metal pipe material on the basis that utilizes original drawing equipment and mould; Satisfy the part producing requirement, solved the difficult problem that little tubing becomes big tubing.Popularization that this is technological and application greatly reduce the raw material tubing stock of enterprise, and there has been the brief feasible way of producing big tubing in the enterprise that makes part can not produce big pipe.

Summary of the invention

Present expanding processing metal tubing has two kinds of technologies: the hole enlargement of first plunging: on hydraulic press, diameter being pressed into tubing inside greater than the plug or the core print of the internal diameter of pipe or semifinished tube, is that pipe internal diameter enlarges, and wall thickness, length reduce; It two is stretching hole enlargements: with stretching-machine the core print of diameter pipe internal diameter is pulled through pipe inside, pipe internal diameter is enlarged, wall thickness, length reduce.First kind is suitable for the hole enlargement of short size semihard pipe; Second method is owing to want each drawing core bar and core print, and fixedly pipe is difficult, and can not realize the drawing of calibrating strap external mold.The invention of this technology is through end sawing opening; Simplified the hole enlargement process, made that the hole enlargement production of metal pipe material is the same as the common tubing of drawing; The process of just Duo together tubing punching repeatedly and having loaded and unloaded core print than traditional undergauge drawing process is that present hole enlargement metal tube is produced on the largest scaleization, optimum production method.

The object of the invention; Be to provide a kind of process of cold-drawn stretching expanding metal tube, solved the practical application technical problem of tubule change bassoon, this process technology is simple; Lumber recovery is high; Need not acquire new equipment, core print, external mold only are to use common drawing core print external mold to get final product, and the pipe performance of production is stable, quality is high.

The objective of the invention is to realize like this; With the metal pipe material of treating expanding one end sawing opening vertically; The other end imports core bar into; Openend exposes behind the core bar fixedly core print, and operator's both hands metal tube of holding with a firm grip hits the first end of fixed core, makes the core print that fixes enter into tubing opening root or more inside; Begin sky on being clipped in openend about 2/3 part before the drawing and draw, must opening being passed with a system machine or artificial system head of external mold sizing is clipped in drawing behind the external mold and clamps and carry out drawing if desired; Directly the tapered core head-clamp is drawn at tubing opening root back head hub disk during the drawing of plate drawing machine kind equipment, it is constant to obtain required pipe internal diameter after passing through the several belt carcass or adding the drawing of external mold sizing controlling dimension expanding, the wall thickness attenuation; Or external diameter is constant, the wall thickness attenuation; Or external diameter increases, the tubing of the size of wall thickness attenuation.

End sawing opening length varies in size according to tubing and gets 100mm～500mm, and the state before the each expanding of tubing is semihard, medium-soft or soft attitude, but the ratio of the low more expanding external diameter of tubing percentage elongation is more little; The used core print of expanding is that the taper core print is used in common drawing; The drawing pincers can not be added to core print and core bar position during drawing.

This process is passed through end axis to the sawing opening; Simplified the hole enlargement process, made that the hole enlargement production of metal pipe material is the same as the common tubing of drawing; The process of just Duo together repeatedly tubing punching bar and having loaded and unloaded core print than traditional undergauge drawing process is that present hole enlargement metal tube is produced on the largest scaleization, optimum production method.

The specific embodiment

Through embodiment the present invention is described further below.

Embodiment 1. produces Φ 80x3 copper tube.The soft attitude red copper pipe of Φ 70x3.5 is opened 1 opening about 150mm length with the toothless saw cutter at one section tube head vertically; Pipe inside penetrates Φ 20 core bars that also are unkitted core print with pipe after pouring into a little Lubrication Solution for Drawing; Opening does not penetrate for one section; After treating that openend exposes the core bar fastening end, the fixing core print of Φ 68.5 in the core bar fastening end, the long taper surface part of core print is towards core bar; The copper pipe of firmly wrenching makes core bar, core print enter into the root of cuts or more inwards, the cuts pipe end is clipped in the copper tube that carries out obtaining after the drawing Φ 75x3.35 specification on the drawing pincers.After the position sawing that added before this copper tube drawing fallen, open the opening of 1 150mm about long one section of tubing vertically again, the copper tube that pipe inside pours into after a little Lubrication Solution for Drawing Φ 75x3.35 penetrates Φ 20 core bars that also are unkitted core print; Opening does not penetrate for one section; After treating that openend exposes the core bar fastening end, the fixing core print of Φ 64 in the core bar fastening end, the long taper surface part of core print is towards core bar; The copper pipe of firmly wrenching makes core bar, core print enter into the root of cuts or more inwards; With passing the external mold that fixes Φ 80 behind the artificial system head of cuts pipe end, be clipped on the drawing pincers, the copper pipe outside continues to add proper lubrication liquid and carries out obtaining Φ 80x3 copper tube after the drawing; The sawing end obtains satisfactory copper tube after the straightening.

Embodiment 2. produces the common aluminum pipe of Φ 30x1.With the soft half-hard state red copper pipe of Φ 28x1.2 with the toothless saw cutter at one end tube head open the opening of 1 100mm about long vertically; Tube interior penetrates Φ 15 core bars that also are unkitted core print with pipe after pouring into a little Lubrication Solution for Drawing, and opening does not penetrate for one section, treat that openend exposes the core bar fastening end after; The fixing core print of Φ 28 in the core bar fastening end; The long taper surface of core print part is towards core bar, and the aluminum pipe of firmly wrenching makes core bar, core print enter into the root of cuts or more inwards, with passing the external mold that fixes Φ 30 behind the cuts pipe end system head mechanism head; Be clipped in afterwards on the drawing pincers; The copper pipe outside continues to add the aluminum pipe that proper lubrication liquid carries out obtaining after the drawing Φ 30x1, and the sawing end obtains satisfactory aluminum pipe after the straightening.

Claims

1. the process of a cold-drawn stretching expanding metal tube; It is characterized in that common metal pipe or tubing one end along pipe all sawings 1～4 direct-axis to opening; The tubing other end is pierced into core bar; The tubing openend pierces into core print (threaded in this way core print directly is anchored on the core bar end and gets final product), fastening core print after exposing the core bar fastening end; The both hands metal tube of holding with a firm grip hits the first end of fixed core then; Make core bar, core print enter into the root of cuts or more inwards, directly open end about 2/3 parts are clipped on the drawing pincers and carry out drawing, must opening be passed with a system machine or artificial system head like band external mold sizing expanding and be clipped in drawing behind the external mold and clamp and carry out drawing; Directly the tapered core head-clamp is drawn at tubing cuts root back head hub disk during the drawing of plate drawing machine kind equipment, it is constant to obtain required pipe internal diameter after passing through the several belt carcass or adding the drawing of external mold sizing controlling dimension expanding, the wall thickness attenuation; Or external diameter is constant, the wall thickness attenuation; Or external diameter increases, the tubing of wall thickness attenuation.

2. according to the process of the said cold stretch expanding of claim 1 metal tube, the machinery equipment that it is characterized in that the expanding metal tube is that vertical pulling drawbench such as all kinds of chain types and hydraulic pressure and all kinds of dish draw drawbench.

3. according to the process of the said cold stretch expanding of claim 1 metal tube, the tubing that it is characterized in that the expanding metal tube is the metal tube of all kinds of materials.

4. according to the process of the said cold stretch expanding of claim 1 metal tube, it is characterized in that treating that the axially open of tubing sawing of the metal tube of expanding is 1～4, the best is 1～2.

5. according to the process of the said cold stretch expanding of claim 1 metal tube, it is characterized in that treating that the axially open of tubing end sawing of the metal tube of expanding is that 100mm～500mm is long.

6. according to the process of the said cold stretch expanding of claim 1 metal tube, it is characterized in that treating that the pipe internal diameter of the metal tube of expanding is Φ 6mm～Φ 200mm.

7. according to the process of the said cold stretch expanding of claim 1 metal tube, it is characterized in that the internal diameter that used core print is equal to or greater than needs expanding tubing.

8. according to the process of the said cold stretch expanding of claim 1 metal tube, it is characterized in that tubing cold stretch expanding after internal diameter constant, the wall thickness attenuation; Or external diameter is constant, the wall thickness attenuation; Or external diameter increases, the wall thickness attenuation.

9. according to the process of the said cold stretch expanding of claim 1 metal tube, it is characterized in that its state of metal pipe material before each expanding is semihard, medium-soft or soft attitude.