CN100391728C - Standing mold pressing die for bars in hard alloy, and manufacturing method - Google Patents

Standing mold pressing die for bars in hard alloy, and manufacturing method Download PDF

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CN100391728C
CN100391728C CNB2006100861330A CN200610086133A CN100391728C CN 100391728 C CN100391728 C CN 100391728C CN B2006100861330 A CNB2006100861330 A CN B2006100861330A CN 200610086133 A CN200610086133 A CN 200610086133A CN 100391728 C CN100391728 C CN 100391728C
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core rod
demoulding
split core
mould
die sleeve
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CN1915654A (en
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杨汉民
龚向军
刘鹏飞
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Suzhou Xinrui Alloy Tool Co.,Ltd.
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SUZHOU JIANGZUAN XINRUI HARD ALLOY CO Ltd
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Abstract

A vertical die set for manufacturing hard alloy rod by die pressing is composed of upper and lower punch heads, die sleeve with demoulding conicity and split die core which demoulding conicity. Its manufacture includes such steps as making the demoulding conicity of die sleeve and die core, grinding the inner surface of die sleeve, longitudinally cutting die core to divide it into several blocks, splicing them, dot welding on end face, grinding the external and internal surfaces of die core, and removing the weld scar.

Description

The mould of vertical mould hard alloy bar and manufacture method thereof
Technical field
The present invention relates to a kind of mould of mold pressing hard alloy bar, relate in particular to a kind of mould and manufacture method thereof of vertical mould hard alloy bar.
Background technology
At present, produce hard alloy bar and mainly adopt modes such as extruding, mold pressing and isostatic cool pressing.And press moulding mode can only be used to suppress ratio of height to diameter less than 5 bar blank, makes axially long, radially little larger ratio of height to diameter bar blank static pressure or extrusion forming technology such as employing usually.
Bar is produced in extrusion modling, and its length is unrestricted, but the bar blank need add the forming agent more than 20%.A large amount of forming agents is difficult for removing, and easily goods is polluted, and at the inner hole that produces of alloy, to bringing certain influence in service life of alloy.And the forming agent skewness in the extruded bars blank, defectives such as cobalt lake appear in alloy inside behind the sintering, thereby reduce the service life of alloy; Usually extrusion equipment and technology cost are quite high.
Isostatic cool pressing is that powder is contained in the jacket, adopts the three-dimensional mode that loads, and makes the powder uniform-compression, then pressed compact is taken out in the cold isostatic press cavity, removes jacket, can obtain pressed compact.In order to obtain the blank of qualified shape, also need adopt special lathe that its surface irregularity place is carried out turning and handle.Adopt isostatic cool pressing compacting bar, the production efficiency of blank is not high.
Horizontal molding die as shown in Figure 1, has radian towards an actor's rendering of an operatic tune up and down, and the powder pine of different parts is adorned ratio, the compression ratio great disparity is bigger, and blank cracks at radian and rib junction easily, and product percent of pass is lower, can't realize suitability for industrialized production.And blank must remove two ribs through turning processing, has increased the anti-grinder preface of turning operation and soft paste waste material, and production cost is higher, also causes powder loss and pollution easily.
Common vertical mould mould is made up of the former that dashes up and down and have a carbide alloy core rod, as shown in Figure 2.The powder-product ratio of height to diameter is big more, and the loss of pressed compact pressing pressure is big more, if adopt unidirectional compacting, the density contrast at position is apart from bigger about the pressed compact; If adopt two-way compacting, the middle part density of blank is lower than two ends.When the mobile pressed compact demoulding, because the density contrast of pressed compact different parts is apart from bigger, when deviating from former, the elastic after effect of different parts is different, causes pressed compact to come off successively, final pressed compact compacting failure.
Summary of the invention
The mould and the manufacture method thereof that the purpose of this invention is to provide a kind of vertical mould hard alloy bar, be intended to effectively solve compacting bar blank and be easy to generate problems such as crackle and fracture, the postorder machining of cancellation blank improves the production work efficiency, reduces production costs; This mould can be widely used in making the bar blank of larger ratio of height to diameter.
Purpose of the present invention is achieved through the following technical solutions:
The mould of vertical mould hard alloy bar, comprise former and last low punch, it is characterized in that: described former is made up of die sleeve that has demoulding tapering and the split core rod that has demoulding tapering, and the demoulding cone angle of split core rod external diameter is consistent with the demoulding cone angle of die sleeve internal diameter.
Further, the mould of above-mentioned vertical mould hard alloy bar, described demoulding cone angle are 0.5 °~3 °; Described split core rod can longitudinally be decomposed into 2~6; The fit system of described split core rod and die sleeve is a matched in clearance; The material of described split core rod is carbide alloy or tool steel, and the material of die sleeve is the 45# steel.
Again further, the manufacture method of vertical mould hard alloy bar timber die is characterized in that comprising following operation---
1. external diameter and the demoulding cone angle to internal diameter, demoulding cone angle and the split core rod of die sleeve carries out roughing;
2. with both ends of the surface about die sleeve and the split core rod prepackage back plain grinding;
3. finish grind the inner surface of die sleeve;
4. with split core rod cutting whole into sections longitudinally;
5. with after each piecemeal amalgamation of split core rod in upper and lower end face place spot-welded on;
6. finish grind split core rod external diameter, the demoulding cone angle of its demoulding cone angle and die sleeve internal diameter is matched;
7. finish grind honing split pattern in-core footpath;
8. trim, and at the bottom of each piecemeal of split core rod mark mark.
The outstanding substantive distinguishing features and the obvious improvement of technical solution of the present invention is mainly reflected in:
1. the present invention will have the die sleeve and the split core rod composition former that has demoulding tapering of demoulding tapering, changed the demoulding principle of traditional vertical mold pressing, adopt static stripping means, after the powder compacting core rod and bar blank integral body are deviate from, then core rod is taken apart, blank takes out in core rod, effectively avoids blank that relative displacement takes place in former, thereby eliminates the crackle or the fracture of blank;
2. shortened stripping stroke, obviously reduced demould time and demoulding danger, alleviated working strength of workers, the not only convenient but also safety of the demoulding;
3. the blank that adopts mould of the present invention to suppress, its Density Distribution is more even, and need not soft processing, blank behind sintering, the inner no cobalt of alloy lake, residual carbon, defectives such as flawless;
4. this mould can be widely used in making the bar blank of larger ratio of height to diameter, production efficiency height, good product quality.
Description of drawings
Below in conjunction with accompanying drawing technical solution of the present invention is described further:
Fig. 1: the cutaway view of the horizontal molding die of background technology;
Fig. 2: the cutaway view of background technology vertical mould mould;
Fig. 3: the cutaway view of mould of the present invention;
Fig. 4: the vertical view of mould of the present invention;
Fig. 5: the cutaway view when mould of the present invention is suppressed;
Fig. 6: the cutaway view during mold releasability of the present invention.
The implication of each Reference numeral sees the following form among the figure.
Reference numeral Implication Reference numeral Implication Reference numeral Implication
1 Upper punch 2 Former 3 Low punch
Reference numeral Implication Reference numeral Implication Reference numeral Implication
4 Die sleeve 5 The split core rod 51 First fen core rod
52 Second fen core rod 53 The 3rd fen core rod 6 The bar blank
The specific embodiment
For problems such as the crackle that effectively solves compacting bar blank and fractures, the postorder machining of cancellation blank improves the production work efficiency, reduces production costs, and the invention provides a kind of mould and manufacture method and application of vertical mould hard alloy bar.
As shown in Figure 3, Figure 4, the mould of vertical mould hard alloy bar of the present invention, comprise upper punch 1 and low punch 3, form former by die sleeve 4 that has demoulding tapering and the split core rod 5 that has demoulding tapering, the demoulding cone angle of the demoulding cone angle of split core rod 5 external diameters and die sleeve 4 internal diameters matches.Split core rod 5 can longitudinally be decomposed into first fen core rod 51, second minute core rod 52 and the 3rd fen core rod 53, when being used for slug press, can be in one to be put die sleeve 4 into each impartial piecemeal core rod amalgamation, and die sleeve 4 adopts gap fiting modes with split core rod 5; The material of split core rod is carbide alloy or tool steel, and the material of die sleeve is the 45# steel.
In the technical solution of the present invention, preferred demoulding cone angle is 0.5 °~3 °.Demoulding cone angle α commonly used represents, means the cone angle of die sleeve or the pairing circular cone of core rod.Sometimes also represent C=(D-d)/H=2 * tg (α/2) in this area with demoulding tapering C.For core rod, wherein: the big footpath (external diameter) of D finger print core, the path (external diameter) of d finger print core, the height of H finger print core.Corresponding with above-mentioned demoulding cone angle scope, the scope of demoulding tapering is 1: 125~1: 20.
Concrete operation of making vertical mould hard alloy bar timber die is: 1. external diameter and the demoulding cone angle to internal diameter, demoulding cone angle and the split core rod 5 of die sleeve 4 carries out roughing; 2. with both ends of the surface about die sleeve 4 and the split core rod 5 prepackage back plain grindings; 3. finish grind the inner surface of die sleeve 4, make inner surface reach good roughness; 4. adopt line cutting that split core rod 5 longitudinally is divided into first fen core rod 51, second minute core rod 52 and the 3rd fen core rod 53; 5. with after first fen core rod 51, second fen core rod 52 and core rod 53 amalgamations in the 3rd fen in place, upper and lower end face spot-welded on; 6. finish grind split core rod external diameter, the demoulding tapering of its demoulding tapering and die sleeve internal diameter is matched, and guarantee surface roughness; 7. finish grind honing split pattern in-core footpath; 8. trim, and, according to the mark sequence number each piecemeal core rod 51,52,53 is combined in one and puts in the die sleeve 4 at first fen core rod 51, second minute core rod 52 and the 3rd fen core rod 53 bottoms mark mark.
Mould of the present invention can be used on the handpress produces the hard alloy bar blank, as shown in Figure 5, it should be noted that when producing the larger ratio of height to diameter hard alloy bar, in the die cavity powder can with die wall generation relative displacement, have the pressure loss.If adopt unidirectional compacting, the powder power that is squeezed in bottom is little, and then Di Bu green density is lower; Adopt two-way compacting, then the density of middle part is lower than two ends; For in the middle of shortening as far as possible with the density contrast of two-end part, repeatedly adorn powder and repeatedly compacting and the suitable height of adjustment lower limit pad simultaneously.Forming agent is controlled at 2.0~2.5% scopes, and forming agent is evenly distributed in soft paste.
It should be noted that, prior art, the main cause that adopts the vertical mould mode can not suppress the larger ratio of height to diameter product is: the pressurized pressure loss of pressed compact causes the green density of pressed compact different parts inhomogeneous, the compact strength of different parts does not wait, during the demoulding, cause pressed compact to drop successively after the pressed compact generation elasticity, can't produce the product of larger ratio of height to diameter at all.Technical solution of the present invention has changed the demoulding principle of traditional vertical mold pressing, avoided the compacting defective of vertical mould, and adopt static stripping means, that is: powder is after removable split pattern in-core compacting, split core rod 5 and bar blank 6 integral body are deviate from, then split core rod 5 is taken apart and be decomposed into first fen core rod 51, second minute core rod 52 and the 3rd fen core rod 53, blank takes out in core rod; Effectively avoid blank that relative displacement takes place in former, thereby eliminated the crackle and the fracture of blank.Mold releasability of the present invention, as shown in Figure 6, concrete knockout course is: demoulding pad on pad below the die sleeve 4, on core rod, place knockout pin, apply very little ejection pressure, because there is demoulding tapering in split core rod 5 with die sleeve 4, bar soft paste 6 is put in minute core rod 51,52,53 and the successful demoulding in company with it by bag; Therefore, need only adopt the high demoulding pad of about 5mm and the knockout pin of equal height, not need to adopt the demoulding pad and the knockout pin that exceed former length, shorten stripping stroke, obviously reduce demould time and demoulding danger, alleviate working strength of workers.
Adopt mould of the present invention to produce
Figure C20061008613300071
10.8mm * 100mm,
Figure C20061008613300072
20.0mm * 120mm, 15.0mm the bar blank of larger ratio of height to diameter such as * 120mm.Blank pressed density distribution uniform, and need not soft processing, blank behind sintering, the inner no cobalt of alloy lake, residual carbon, defectives such as apparent flawless.The not only convenient but also safety of modern design of the present invention, the demoulding, production efficiency height, this mould are widely used in making the bar blank of 0.5~10 larger ratio of height to diameter, good product quality.
More than by specific embodiment technical solution of the present invention has been done to further specify, the example that provides only is an exemplary applications, can not be interpreted as a kind of restriction to claim protection domain of the present invention.

Claims (6)

1. the mould of vertical mould hard alloy bar, comprise former and last low punch, it is characterized in that: described former is made up of die sleeve that has demoulding tapering and the split core rod that has demoulding tapering, and the demoulding cone angle of split core rod external diameter is consistent with the demoulding cone angle of die sleeve internal diameter.
2. the mould of vertical mould hard alloy bar according to claim 1 is characterized in that: described demoulding cone angle is 0.5 °~3 °.
3. the mould of vertical mould hard alloy bar according to claim 1 is characterized in that: described split core rod can longitudinally be decomposed into 2~6.
4. the mould of vertical mould hard alloy bar according to claim 1 is characterized in that: the fit system of described split core rod and die sleeve is a matched in clearance.
5. the mould of vertical mould hard alloy bar according to claim 1 is characterized in that: the material of described split core rod is carbide alloy or tool steel, and the material of die sleeve is the 45# steel.
6. the manufacture method of vertical mould hard alloy bar timber die is characterized in that comprising following operation:
1. external diameter and the demoulding cone angle to internal diameter, demoulding cone angle and the split core rod of die sleeve carries out roughing;
2. with both ends of the surface about die sleeve and the split core rod prepackage back plain grinding;
3. finish grind the inner surface of die sleeve;
4. with split core rod cutting whole into sections longitudinally;
5. with after each piecemeal amalgamation of split core rod in upper and lower end face place spot-welded on;
6. finish grind split core rod external diameter, the demoulding cone angle of its demoulding cone angle and die sleeve internal diameter is matched;
7. finish grind honing split pattern in-core footpath;
8. trim, and at the bottom of each piecemeal of split core rod mark mark.
CNB2006100861330A 2006-09-01 2006-09-01 Standing mold pressing die for bars in hard alloy, and manufacturing method Active CN100391728C (en)

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CN101972925B (en) * 2010-10-21 2013-02-13 浙江东钨实业有限公司 Method for processing molding die used in hard alloy production
CN103192230B (en) * 2013-04-22 2015-09-09 中铁科工集团有限公司 Deep hole processing method and the slip casting block prepared
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JPH1157843A (en) * 1997-08-26 1999-03-02 Tokyo Seiko Co Ltd Wire drawing die and grinding method therefor
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