CN101543874A - Die forging method based on screw press - Google Patents
Die forging method based on screw press Download PDFInfo
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- CN101543874A CN101543874A CN200910137388A CN200910137388A CN101543874A CN 101543874 A CN101543874 A CN 101543874A CN 200910137388 A CN200910137388 A CN 200910137388A CN 200910137388 A CN200910137388 A CN 200910137388A CN 101543874 A CN101543874 A CN 101543874A
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Abstract
The present invention discloses a die forging method based on screw press, wherein the die forging method comprises the following steps: 1. placing a closed die on a second station of screw press, fixedly installing the upper die of closed die on a slider and fixedly installing the lower die of closed die on a worktable; obtaining a required maximum hitting power according to the character of stock, temperature, friction coefficient between the stock and the die, and the shape and size of forged piece, and adjusting the hitting energy of screw press; 2. baiting; 3. heating the stock; 4. placing the heated stock to a first station of screw press for pre-pressing; 5. placing the stock obtained after pre-pressing to the second station of screw press for final-pressing; and 6. lifting the slider of screw press for ejecting the forged piece by the lower ejector rod. The method of the invention fully exerts the advantages of closed die forging technique and has the advantages of higher usage factor of material and no requirement for edge cutting procedure after forging forming. Obviously, the manufacturing cost of product is greatly saved and the processing efficiency is greatly increased.
Description
Technical field
The present invention relates to the die forging method of technical field of forging, be specifically related to a kind of die forging method based on fly press.
Background technology
Fly press has obtained widely using in metal working process, and its adopts screw rod, nut as transmission mechanism, changes the forward and reverse gyration of flywheel into slide block pump.During work, dynamical system drives flywheel and quickens rotation with stored energy, promotes slide block by screw rod, nut simultaneously and moves downward, and it does not have fixing bottom dead centre.When the slide block contact workpiece, flywheel is forced to be decelerated to fully and stops, and the rotation function of storage changes impact energy into, hits workpiece by slide block and produces plastic deformation.
Have not the fixedly characteristics of bottom dead centre based on fly press, employed die forging method is open die forging, impressing forging technology on the existing fly press,, with respect to perpendicular to force direction, has horizontal overlap around the forging die joint that is; Blank is reserved with bigger overlap allowance in this process, like this, hit in the process of blank in forging and pressing, flow into by the surplus metal in the flash gutters of open die, guarantee that the bottom dead centre of fly press satisfies the dimensional requirement of forging to absorb unnecessary energy; Thereby the security reliability that meets contour forging technique.
But above-mentioned process is used and is existed many defectives: one, and forging exists bigger overlap, the operation of need cutting edge; Its two, upper and lower closed-die forging easily produces the mismatch phenomenon, need to reserve bigger allowance; Its three, die life is lower; Its four, stock utilization is lower, the loss of overlap metal is bigger, usually overlap accounts for more than 20% of forge weight, sometimes up to more than 100%.Obviously, employed die forging method carries out forging processing on the existing fly press of application, exists the problem that processing cost is higher and production efficiency is low excessively.
As everyone knows, die forging is divided into two kinds of open die forging, impressing forging and closed die forgings, both comparatively speaking, closed die forging does not form horizontal overlap, also claim no-flash die forging, thereby can obtain the forging that geometry, dimensional accuracy and surface quality approach product parts to greatest extent, and then improve stock utilization.Yet, since during closed die forging the stock metal in the impression of sealing, be shaped and the blank surplus less, thereby need control the impulse stroke of patrix accurately.At present, be limited to the not fixing characteristics of bottom dead centre of fly press, in the production practices of die forging, can't with the closed die forging process application in fly press.
In view of this, demand urgently looking for another way and develop a kind of die forging method based on fly press, with the closed die forging process application in fly press, with the high advantage of stock utilization that makes full use of closed die forging technology.
Summary of the invention
At above-mentioned defective, the technical problem that the present invention solves is, provide a kind of with the die forging method of closed die forging process application in fly press, with the high advantage of stock utilization that makes full use of closed die forging technology, effectively solve the above-mentioned defective that employed die forging method exists on the existing fly press.
Die forging method based on fly press provided by the invention, undertaken by following step:
One, closed molds is placed second station of fly press, its patrix is fixedly installed on the slide block, and its counterdie is fixedly installed on the workbench; Geomery according to coefficient of friction between character, temperature, blank and the mould of stock and forging obtains needed maximum hitting power, and sets up the blow energy of fly press;
Two, blanking;
Three, blank is carried out heat treated;
Four, the blank after will heating places first station of fly press to carry out pre-pier to handle;
Five, the blank that obtains behind the pre-pier is placed second station of fly press carry out whole pier processing;
Six, the slide block of fly press is up, ejects forging by lower push rod.
Preferably, in the step 1, adopt finite element system simulation softward DEFORM-3D to obtain needed maximum hitting power.
Preferably, in the step 2, adopt the blanking of sawing mode, the dimensional tolerance of blank is 2mm, and the shear-face angle tolerance of blank is 3 °.
Preferably, in the step 3, adopt Medium Frequency Induction Heating Furnace to carry out heat treated.
Preferably, step 4 is identical with needed maximum hitting power in the step 5.
Preferably, being once in step 4 and the step 5, strike is shaped.
Preferably, after finish-forging was shaped, the fit clearance between the upper and lower mould was less than 0.3mm.
Preferably, in the step 5, the finish-forging curring time is 0.05s～0.1s.
Preferably, in the step 6, push rod specifically is set to three, and three push rods are circumferentially uniform along the center of counterdie.
Preferably, to lead the cooperation pattern draft of lock be 2～3 ° to the upper and lower mould of closed molds.
Die forging method based on fly press provided by the invention has adopted closed die forging technology, set up the blow energy of fly press in advance at different forging, make that the blow energy of fly press is identical with the needed work of deformation of forging forming, after operation is finished, the lower dead point position of fly press meets the patrix of closed molds and the gap requirement between the counterdie, therefore, this method when guaranteeing the requirement of finished product forging quality, reliably with the closed die forging process application in fly press.Based on this, this method has been given full play to the advantage of closed die forging technology, the operation of need not cutting edge behind the higher and forging and molding of stock utilization, obviously, the manufacturing cost and the working (machining) efficiency of having saved product greatly.
In this method, the needed work of deformation of forging forming, promptly the needed maximum hitting power of forging forming can be determined according to the geomery of coefficient of friction between character, temperature, blank and the mould of stock and forging.In the preferred version of die forging method of the present invention, adopt finite element system simulation softward DEFORM-3D to determine needed maximum hitting power, at first, in DEFORM-3D, set up and forge preprocessed file, import blank model, the upper and lower mould model of STL form; Then, temperature, the material of blank model is set, relevant parameters such as the temperature of upper and lower mould, movement velocity; At last, generate analog result, obtain the needed hitting power of forging forming.Obviously, adopt DEFORM-3D software to obtain result of calculation to have precisely, advantage efficiently, and can adjust the blank model at any time to select the most optimum technological parameter.Particularly for complicated parts, mould, it precisely, advantage is particularly outstanding efficiently.
Description of drawings
Fig. 1 is the front view of forging one among the embodiment one;
Fig. 2 is the side view of forging one among the embodiment one;
Fig. 3 is the overall structure schematic diagram of used closed molds among the embodiment one;
Fig. 4 is the vertical view of Fig. 3;
Fig. 5 is the front view of forging two among the embodiment two;
Fig. 6 is the front view of forging three among the embodiment three;
Fig. 7 is the front view of forging four among the embodiment four.
The specific embodiment
The present invention is with the die forging method of closed die forging process application in fly press, with the high advantage of stock utilization that makes full use of closed die forging technology.Concrete steps are as follows:
One, closed molds is placed second station of fly press, its patrix is fixedly installed on the slide block, and its counterdie is fixedly installed on the workbench; Geomery according to coefficient of friction between character, temperature, blank and the mould of stock and forging obtains needed maximum hitting power, and the blow energy of setting fly press, so that the lower dead point position of fly press meets the patrix of closed molds and the gap requirement between the counterdie.
Self precision of positioning accuracy between the upper and lower mould and equipment has direct relation, thereby has effectively avoided the matched moulds mismatch.Wherein, required maximum hitting power can be determined according to the computational methods of conventional forging process, also can use finite element system simulation softward DEFORM-3D and obtain needed maximum hitting power.
Two, blanking.
Three, blank is carried out heat treated.The selection of firing equipment is identical with existing contour forging technique in this step.Preferably, adopt Medium Frequency Induction Heating Furnace, reducing the imitation frosted glass loss, and the uniformity of blank temperature can guarantee die forging the time.
Four, the blank after will heating places first station of fly press to carry out pre-pier to handle; On the theory, pre-pier is handled and also can be carried out on Forgingother equipment.But in order to improve forging production efficiency, pre-pier of this method and whole pier operation are carried out on same equipment.
Five, the blank that obtains behind the pre-pier is placed second station of fly press carry out whole pier processing; Preferably, whole pier is identical with the pre-needed hitting power of pier operation, like this, once sets up the blow energy of equipment, can carry out blocking, finish-forging operation successively, once hits to be shaped further to enhance productivity.
Six, the slide block of fly press is up, ejects forging by lower push rod.
Specify below in conjunction with different embodiment.
Embodiment 1:
See also Fig. 1 and Fig. 2, wherein, Fig. 1 is the front view of forging one in the present embodiment; Fig. 2 is the side view of forging one in the present embodiment.
As shown in the figure, forging one is the disc-like product, and material is No. 40 steel, and diameter is 235mm, highly is 70mm.
See also Fig. 3, this figure is the closed molds of forging one in the present embodiment.The cooperation pattern draft that the upper and lower mould of closed molds is led lock is 2～3 °.
Present embodiment carries out on the 25000KN high power screw press.In the technological design, with the blanking of φ 100mm round steel, cutting stock weight is 7.7kg; Obtaining maximum hitting power based on the analog result of DEFORM-3D software is 21000kN.In fact, the determining and can calculate according to the computational methods of conventional forging process of maximum hitting power in this example do not repeat them here.
The concrete technological parameter of present embodiment is as follows:
1) the raw material cylindrical need not processed, and does not need surface treatment, and blanking tolerance is 2mm, and sawing allows in 3 ° of the deflections, is embodied in that tolerance is 0.36 on the forging, meets the size tolerance requirements of part;
2) adopt Medium Frequency Induction Heating Furnace; Be 11min heat time heating time, and this moment, blank temperature was 1200 ℃;
3) blocking operation, the slide block range of fly press is 600mm, blank is upset into round pie; After hitting end, motor makes the flywheel counter-rotating, drives slide block and rises, and gets back to the home position;
4) finish-forging operation, the slide block range of fly press is 500mm, touches in the forging forming process at patrix and jumping-up cake, and the patrix stroke is 17mm, and molding time is 0.05～0.1s; After finish-forging was shaped, the fit clearance between patrix 1 and the counterdie 2 was 0.2mm.
The liftout tank of 25000KN high power screw press has high pressure and two pumping sources of low pressure, and high-pressure pump can provide enough ejecting forces, and big can the making of low-lift pump flow ejects the very high speed of generation, guarantees that forging goes out mold process finishing rapidly and efficiently.Referring to Fig. 4, this figure is the vertical view of Fig. 3.Present embodiment adopts three push rods 3 with the liftout tank interlock so that eject in the process stressed evenly, forging obliquity effects depanning efficient when avoiding depanning.
Compared with prior art, this method molding time is short, thereby the mold temperature variation is little, and fatigue life is long.In addition, upper and lower mould is by bolt and voussoir and is positioned on the template of equipment, and the positioning accuracy between the forging process upper and lower mould can reach 0.2 millimeter, satisfies the production requirement of this product.
Embodiment 2:
See also Fig. 5, this figure is the front view of forging two in the present embodiment.
As shown in the figure, forging two is the disc-like product, and material is No. 40 steel, and diameter is 235mm, highly is 70mm.The cooperation pattern draft that the upper and lower mould of closed molds is led lock is 2～3 °.
Present embodiment carries out on the 25000KN high power screw press.In the technological design, with the blanking of φ 100mm round steel, cutting stock weight is 7.1kg; Obtaining maximum hitting power based on the analog result of DEFORM-3D software is 21000kN.Equally, in this example maximum hitting power determine also can calculate according to the computational methods of conventional forging process.
The concrete technological parameter of present embodiment is as follows:
1) the raw material cylindrical need not processed, and does not need surface treatment, and blanking tolerance is 2mm, and sawing allows in 3 ° of the deflections, is embodied in that tolerance is 0.34 on the forging, meets the size tolerance requirements of part;
2) adopt Medium Frequency Induction Heating Furnace; Be 11min heat time heating time, and this moment, blank temperature was 1200 ℃;
3) blocking operation, the slide block range of fly press is 590mm, blank is upset into round pie; After hitting end, motor makes the flywheel counter-rotating, drives slide block and rises, and gets back to the home position;
4) finish-forging operation, the slide block range of fly press is 490mm, touches in the forging forming process at patrix and jumping-up cake, and the patrix stroke is 14mm, and molding time is 0.05～0.1s; After finish-forging was shaped, the fit clearance between the upper and lower mould was 0.1mm.
Embodiment 3:
See also Fig. 6, this figure is the front view of forging three in the present embodiment.
As shown in the figure, forging three is the disc-like product, and material is aluminium manganese brass (HMn52-2-5), and density is 8.5g/cm
3, diameter is 240mm, highly is 85mm.The cooperation pattern draft that the upper and lower mould of closed molds is led lock is 2～3 °.
Present embodiment carries out on the 25000KN high power screw press.In the technological design, with the blanking of φ 130mm raw material, cutting stock weight is 18kg; Obtaining maximum hitting power based on the analog result of DEFORM-3D software is 23000kN.Equally, in this example maximum hitting power determine also can calculate according to the computational methods of conventional forging process.
The concrete technological parameter of present embodiment is as follows:
1) the raw material cylindrical need not processed, and does not need surface treatment, and blanking tolerance is 2mm, and sawing allows in 3 ° of the deflections, is embodied in that tolerance is 0.31 on the forging, meets the size tolerance requirements of part;
2) adopt Medium Frequency Induction Heating Furnace; Be 11min heat time heating time, and this moment, blank temperature was 700 ℃;
3) blocking operation, the slide block range of fly press is 550mm, blank is upset into round pie; After hitting end, motor makes the flywheel counter-rotating, drives slide block and rises, and gets back to the home position;
4) finish-forging operation, the slide block range of fly press is 450mm, touches in the forging forming process at patrix and jumping-up cake, and the patrix stroke is 30mm, and molding time is 0.05～0.1s; After finish-forging was shaped, the fit clearance between the upper and lower mould was 0.2mm.
Embodiment 4:
See also Fig. 7, this figure is the front view of forging four in the present embodiment.
As shown in the figure, forging four is the disc-like product, and material is aluminium alloy (L1), and density is 2.7g/cm
3, diameter is 300mm, highly is 65mm.The cooperation pattern draft that the upper and lower mould of closed molds is led lock is 2～3 °.
Present embodiment carries out on the 25000KN high power screw press.In the technological design, with the blanking of φ 150mm raw material, cutting stock weight is 7.5kg; Obtaining maximum hitting power based on the analog result of DEFORM-3D software is 25000kN.Equally, in this example maximum hitting power determine also can calculate according to the computational methods of conventional forging process.
The concrete technological parameter of present embodiment is as follows:
1) the raw material cylindrical need not processed, and does not need surface treatment, and blanking tolerance is 2mm, and sawing allows in 3 ° of the deflections, is embodied in that tolerance is 0.27 on the forging, meets the size tolerance requirements of part;
2) adopt Medium Frequency Induction Heating Furnace; Be 11min heat time heating time, and this moment, blank temperature was 450 ℃;
3) blocking operation, the slide block range of fly press is 545mm, blank is upset into round pie; After hitting end, motor makes the flywheel counter-rotating, drives slide block and rises, and gets back to the home position;
4) finish-forging operation, the slide block range of fly press is 445mm, touches in the forging forming process at patrix and jumping-up cake, and the patrix stroke is 25mm, and molding time is 0.05～0.1s; After finish-forging was shaped, the fit clearance between the upper and lower mould was 0.2mm.
To sum up, the die forging method based on fly press of the present invention has been given full play to the advantage of closed die forging technology, the operation of need not cutting edge behind the higher and forging and molding of stock utilization, obviously, the manufacturing cost and the working (machining) efficiency of having saved product greatly.This method be specially adapted to diameter greater than 200mm and ratio of height to diameter less than 0.4 disc forging.
The above only is a preferred implementation of the present invention; should be pointed out that for those skilled in the art, under the prerequisite that does not break away from the principle of the invention; can also make some improvements and modifications, these improvements and modifications also should be considered as protection scope of the present invention.
Claims (10)
- Based on the die forging method of fly press, it is characterized in that 1, this method is undertaken by following step:One, closed molds is placed second station of fly press, its patrix is fixedly installed on the slide block, and its counterdie is fixedly installed on the workbench; Geomery according to coefficient of friction between character, temperature, stock and the mould of stock and forging obtains needed maximum hitting power, sets up the blow energy of fly press;Two, blanking;Three, blank is carried out heat treated;Four, the blank after will heating places first station of fly press to carry out pre-pier to handle;Five, the blank that obtains behind the pre-pier is placed second station of fly press carry out whole pier processing;Six, the slide block of fly press is up, ejects forging by lower push rod.
- 2, the die forging method based on fly press according to claim 1 is characterized in that, in the step 1, adopts the finite element system simulation softward to obtain needed maximum hitting power.
- 3, the die forging method based on fly press according to claim 1 is characterized in that, in the step 2, adopts the blanking of sawing mode, and the dimensional tolerance of blank is 2mm, and the shear-face angle tolerance of blank is 3 °.
- 4, the die forging method based on fly press according to claim 1 is characterized in that, in the step 3, adopts Medium Frequency Induction Heating Furnace to carry out heat treated.
- 5, the die forging method based on fly press according to claim 1 is characterized in that, step 4 is identical with needed maximum hitting power in the step 5.
- 6, the die forging method based on fly press according to claim 5 is characterized in that, is in step 4 and the step 5 once to hit to be shaped.
- 7, the die forging method based on fly press according to claim 6 is characterized in that, after finish-forging was shaped, the fit clearance between the upper and lower mould was less than 0.3mm.
- 8, the die forging method based on fly press according to claim 7 is characterized in that, in the step 5, the finish-forging curring time is 0.05s～0.1s.
- 9, the die forging method based on fly press according to claim 1 is characterized in that, in the step 6, push rod specifically is set to three, and three push rods are circumferentially uniform along the center of counterdie.
- 10, the die forging method based on fly press according to claim 1 is characterized in that, the cooperation pattern draft that the upper and lower mould of closed molds is led lock is 2～3 °.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2009101373889A CN101543874B (en) | 2009-04-29 | 2009-04-29 | Die forging method based on screw press |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2009101373889A CN101543874B (en) | 2009-04-29 | 2009-04-29 | Die forging method based on screw press |
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| CN101543874A true CN101543874A (en) | 2009-09-30 |
| CN101543874B CN101543874B (en) | 2011-01-05 |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102198485A (en) * | 2011-04-20 | 2011-09-28 | 大连大高阀门有限公司 | Die and process for forging No.240 steel ingots for railway locomotives |
| CN103352912A (en) * | 2013-06-30 | 2013-10-16 | 贵州安大航空锻造有限责任公司 | V-shaped crankshaft forging of six-cylinder engine and forging method thereof |
| CN110899594A (en) * | 2019-12-03 | 2020-03-24 | 无锡航亚科技股份有限公司 | Closed forging die and method for metal acetabular outer cup |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2603716Y (en) * | 2003-02-26 | 2004-02-18 | 华中科技大学 | Die forging forming mould of metal extrusion pressing |
| CN100402184C (en) * | 2006-05-22 | 2008-07-16 | 大连大洋阀门研究发展有限公司 | Integrated die forge forming method for flange valve |
-
2009
- 2009-04-29 CN CN2009101373889A patent/CN101543874B/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102198485A (en) * | 2011-04-20 | 2011-09-28 | 大连大高阀门有限公司 | Die and process for forging No.240 steel ingots for railway locomotives |
| CN103352912A (en) * | 2013-06-30 | 2013-10-16 | 贵州安大航空锻造有限责任公司 | V-shaped crankshaft forging of six-cylinder engine and forging method thereof |
| CN103352912B (en) * | 2013-06-30 | 2016-04-27 | 贵州安大航空锻造有限责任公司 | V-six engine crankshaft forging and forging method thereof |
| CN110899594A (en) * | 2019-12-03 | 2020-03-24 | 无锡航亚科技股份有限公司 | Closed forging die and method for metal acetabular outer cup |
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Address after: 161002 Qigihar City, Heilongjiang province Tiefeng District Plant Road No. 36 Patentee after: CRRC QIQIHAR VEHICLE CO., LTD. Address before: 161002 Qigihar City, Heilongjiang province Tiefeng District Plant Road No. 36 Patentee before: Qiqihar Railway Rolling Stock Co., Ltd. |
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