CN104550400A

CN104550400A - Anti-slip tooth design applicable to high-hardness metal sectional material stretching and straightening

Info

Publication number: CN104550400A
Application number: CN201310521903.XA
Authority: CN
Inventors: 石国梁; 张奎; 李兴刚; 李永军; 马鸣龙; 袁家伟
Original assignee: Beijing General Research Institute for Non Ferrous Metals
Current assignee: Beijing General Research Institute for Non Ferrous Metals
Priority date: 2013-10-29
Filing date: 2013-10-29
Publication date: 2015-04-29

Abstract

The invention relates to an anti-slip tooth design applicable to high-hardness metal sectional material stretching and straightening. Anti-slip teeth arranged at a tong jaw of a stretching machine are straight teeth with isosceles-triangle-shaped cross sections, the extending direction of the teeth is vertical to the stretching direction, the height of the teeth is 2 to 5mm, the front bottom angle and the back bottom angle of the anti-slip teeth are 10 degrees to 80 degrees, and the width of a platform among the teeth is 0 to 50mm; or the anti-slip teeth of the tong jaw of the stretching machine are barb-shaped teeth, the extending direction of the teeth is vertical to the stretching direction, the height of the teeth is 2 to 5mm, the front bottom angle of the anti-slip teeth is 10 degrees to 80 degrees, the back bottom angle of the anti-slip teeth is 90 degrees to 170 degrees, and the width of the platform among the teeth is 0 to 50mm. When the anti-slip teeth designed by a method provided by the invention is adopted, the slippage between sectional materials and the tong jaw can be effectively avoided, so that the stretching can be smoothly carried out, and in the use process for high-hardness metal sectional material stretching and straightening, the biting depth of the teeth is proper, so that the fracture due to stress concentration is avoided, in addition, a proper gap is formed among the teeth, and the clamp head skin can be prevented from being easily peeled off.

Description

Be applicable to the anti-slop serrations design of high hard shape tension straingtening

Technical field

The present invention relates to a kind of anti-slop serrations design being applicable to high hard shape tension straingtening, in particular to the design of stretcher jaw anti-slop serrations, belong to the tension straingtening field of shape.

Background technology

Often there is the situation of shape distortion in the shape through pressure processing method manufacture, usually adopts pulling method to align in actual production.Meanwhile, inside is existed to the section bar of residual stress, prestretched can also eliminate residual stress effectively, thus avoids section bar, when follow-up machined, deformation occurs.

Prevent the skidding between stretcher jaw and section bar from being the prerequisite realizing stretching.Stretching-machine has two bare terminal ends, and during stretching, a bare terminal end maintains static, another bare terminal end loading tensile.Each bare terminal end has upper and lower two jaws, and bit is fixed on wedge block, and wedge block is movable on inclined ramp, the upper and lower folding of band movable clamp port.Before loading tensile, bare terminal end applies an initial snap-in force by hydraulic means to jaw, and this snap-in force is not too large, just allows section bar produce depression, or allows the anti-slop serrations on jaw nip section bar, realizes tentatively being engaged; After loading tensile, because the continuation of wedge block on inclined ramp is moved, thus make snap-in force continue to increase, reach the effect of stinging tighter and tighter.For medium-hard material, as aluminium alloy extrusions after great majority quenching, initial snap-in force is enough to allow section bar chuck position produce depression or allows anti-slop serrations nip chuck, thus not easily skid, and for high hardness material, magnesium alloy profiles as higher in content of rare earth, initial snap-in force cannot allow common anti-slop serrations nip jaw face, chuck more cannot be allowed to produce depression, therefore, often firm loading tensile, snap-in force not yet continues to increase, just skid between jaw and chuck, cause stretching to carry out.

The initial snap-in force of stretching-machine bare terminal end is difficult to regulate usually, and feasible method improves the profile of tooth of anti-slop serrations.Fig. 1 (a) and Fig. 1 (b) shows the anti-slop serrations usually adopted, wherein, Fig. 1 (a) is densely arranged stud, and Fig. 1 (b) is greater than the triangular-section straight-tooth of 5mm for tooth depth, and they can meet the stretching requirement of most of section bar, and high for hardness and that plasticity is poor section bar, this kind of profile of tooth is just inapplicable, or cannot nip, or nips too dark and cause broken end, or due to tooth overstocked and chuck epidermis is smoothed out with the fingers in large area, therefore must design new anti-slop serrations targetedly.

Summary of the invention

The present invention, according to the feature of high rigidity shape tension straingtening, provides a kind of jaw anti-slop serrations method for designing.

Technical scheme of the present invention is as follows:

A kind of anti-slop serrations design being applicable to high hard shape tension straingtening, stretcher jaw material is steel, and jaw anti-slop serrations adopts triangular-section straight-tooth, and the bearing of trend of tooth is perpendicular to draw direction.The design of anti-slop serrations needs four key parameters, that is: tooth depth h, front base angle θ ₁, rear base angle θ ₂, between cog berm width w, the physical meaning of parameters is shown in Fig. 2.

For the hard shape of height, preferred scheme has two:

1, isosceles triangle tooth: tooth depth h is 2 ~ 5mm, the front base angle θ of anti-slop serrations ₁be 10 ° ~ 80 °, rear base angle θ ₂be 10 ° ~ 80 °, between cog berm width w is 0 ~ 50mm.Common isosceles triangle straight-tooth design, tooth depth is all greater than 5mm, is not suitable for high hard shape.And found by research of the present invention, for the hard shape of height, tooth depth should be less than 5mm, just can reach the instructions for use of high hard shape.

2, " hangnail " shape tooth: tooth depth h is 2 ~ 5mm, the front base angle θ of anti-slop serrations ₁be 10 ° ~ 80 °, rear base angle θ ₂be 90 ° ~ 170 °, between cog berm width w is 0 ~ 50mm.

In above-mentioned two schemes, between cog berm width w can select 1 ~ 50mm, more preferably 2 ~ 50mm.

After anti-slop serrations processes, Quenching Treatment to be carried out to the jaw top layer at anti-slop serrations place, to promote its hardness and wearability.Meanwhile, the metal fragment between anti-slop serrations should be disposed in time, because debris accumulation can stick with paste anti-slop serrations too much, thus cause skidding.

The anti-slop serrations adopting the inventive method to design effectively can avoid the skidding between section bar and jaw, and stretching is carried out smoothly.Anti-slop serrations of the present invention design when shape tension straingtening hard for height, the degree of depth appropriateness of nipping of tooth, thus the broken end avoiding stress to concentrate causing, and between cog leaves appropriate gap, can prevent chuck epidermis from being smoothed out with the fingers easily.

Accompanying drawing explanation

Fig. 1 (a) and Fig. 1 (b) is the anti-slop serrations usually adopted, and wherein, Fig. 1 (a) is densely arranged stud, and Fig. 1 (b) is triangular-section straight-tooth.

Fig. 2 is four key parameters that design anti-slop serrations is used.

Fig. 3 is for for the anti-slop serrations cross sectional shape designed by high strength rare earth magnesium alloy sheet material.

Fig. 4 is for for the anti-slop serrations cross sectional shape designed by high strength rare earth magnesium alloy square rod.

Detailed description of the invention

Embodiment 1:

When carrying out tension straingtening to superhigh intensity magnesium-rare earth extrusion plate, stud formula anti-slop serrations (Fig. 1 (a)) can not be avoided skidding, and broken end can be caused in common triangular-section straight-tooth (Fig. 1 (b)), has thus redesigned anti-slop serrations.The sheet material of aligning is needed to be of a size of 300mm × 25mm × 10000mm.The tooth profile parameter designed is as follows: tooth depth h=2mm, front base angle θ ₁=rear base angle θ ₂=20 °, between cog berm width w=5mm, profile of tooth cross section as shown in Figure 3.After anti-slop serrations processes, quenched in the jaw top layer at anti-slop serrations place, to promote its hardness and wearability.Meanwhile, dispose the metal fragment between anti-slop serrations in time, avoid debris accumulation can stick with paste anti-slop serrations too much, thus cause skidding.

Practice shows, the anti-slop serrations shown in Fig. 3 effectively can avoid the skidding between jaw and section bar, and the success rate of stretching significantly promotes.The chuck observed after stretching can find: the anti-slop serrations degree of depth of nipping is moderate, and the vestige that epidermis is smoothed out with the fingers by anti-slop serrations does not occur.

Embodiment 2:

Specification be the high strength rare earth magnesium alloy square-section square rod of 210mm × 95mm × 14000mm when tension straingtening, common anti-slop serrations can not effectively avoid skid and broken end, so redesigned anti-slop serrations.Designed tooth profile parameter is as follows: tooth depth h=5mm, front base angle θ ₁=30 °, rear base angle θ ₂=100 °, between cog berm width w=0, profile of tooth cross section as shown in Figure 4.After anti-slop serrations processes, quenched in the jaw top layer at anti-slop serrations place, to promote its hardness and wearability.Meanwhile, dispose the metal fragment between anti-slop serrations in time, avoid debris accumulation can stick with paste anti-slop serrations too much, thus cause skidding.

Through practice, the anti-slop serrations shown in Fig. 4 can effectively be avoided skidding and broken end.

Claims

1. one kind is applicable to the anti-slop serrations design of high hard shape tension straingtening, stretcher jaw material is steel, it is characterized in that: the anti-slop serrations of described stretcher jaw is isoceles triangle tee section straight-tooth, the bearing of trend of tooth is perpendicular to draw direction, tooth depth is 2 ~ 5mm, the front base angle of anti-slop serrations and rear base angle are 10 ° ~ 80 °, and between cog berm width is 0 ~ 50mm.

2. one kind is applicable to the anti-slop serrations design of high hard shape tension straingtening, stretcher jaw material is steel, it is characterized in that: the anti-slop serrations of described stretcher jaw is barb-shaped tooth, the bearing of trend of tooth is perpendicular to draw direction, tooth depth is 2 ~ 5mm, the front base angle of anti-slop serrations is 10 ° ~ 80 °, and rear base angle is 90 ° ~ 170 °, and between cog berm width is 0 ~ 50mm.

3. be applicable to the anti-slop serrations design of high hard shape tension straingtening as claimed in claim 1 or 2, it is characterized in that: described between cog berm width is 1 ~ 50mm.

4. be applicable to the anti-slop serrations design of high hard shape tension straingtening as claimed in claim 3, it is characterized in that: described between cog berm width is 2 ~ 50mm.

5. be applicable to the anti-slop serrations design of high hard shape tension straingtening as claimed in claim 4, it is characterized in that: Quenching Treatment is carried out to the jaw top layer at anti-slop serrations place.