CN110899594A - Closed forging die and method for metal acetabular outer cup - Google Patents

Closed forging die and method for metal acetabular outer cup Download PDF

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Publication number
CN110899594A
CN110899594A CN201911219089.XA CN201911219089A CN110899594A CN 110899594 A CN110899594 A CN 110899594A CN 201911219089 A CN201911219089 A CN 201911219089A CN 110899594 A CN110899594 A CN 110899594A
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CN
China
Prior art keywords
cup
forging
die
bar
guide
Prior art date
Application number
CN201911219089.XA
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Chinese (zh)
Inventor
邹志强
何涛
李湘军
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无锡航亚科技股份有限公司
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Priority to CN201911219089.XA priority Critical patent/CN110899594A/en
Publication of CN110899594A publication Critical patent/CN110899594A/en

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Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21JFORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
    • B21J13/00Details of machines for forging, pressing, or hammering
    • B21J13/02Dies or mountings therefor
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21JFORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
    • B21J5/00Methods for forging, hammering, or pressing; Special equipment or accessories therefor
    • B21J5/02Die forging; Trimming by making use of special dies ; Punching during forging
    • B21J5/025Closed die forging

Abstract

The invention provides a closed forging die for a metal acetabular outer cup, which can solve the problems that the existing metal acetabular outer cup is manufactured by adopting an open die forging process, the process is complicated, the manufacturing period is long, the material utilization rate is low, the filling defect is easy to generate, the adjustment difficulty of forging equipment is high, and the production cost is high. The acetabulum outer cup comprises a punch and a female die, wherein the female die is provided with a vertically through die cavity, the die cavity comprises a guide cylinder, a die cavity and an extrusion opening which are sequentially and coaxially communicated from top to bottom, and the shape of the die cavity is adapted to the shape of the acetabulum outer cup; the bottom surface of the punch is provided with a guide part and a forming part which are coaxially arranged from top to bottom, the guide part is in clearance fit with the guide cylinder, and the shape of the forming part is adapted to the inner shape of the acetabulum outer cup. Meanwhile, the invention also provides a closed forging method of the metal acetabular outer cup.

Description

Closed forging die and method for metal acetabular outer cup

Technical Field

The invention relates to the field of artificial joint machining and manufacturing, in particular to a closed forging die and a closed forging method for a metal acetabulum outer cup.

Background

The metal acetabulum outer cup is an artificial joint implant and is used as a replacement for implanting into a human hip joint when an orthopedic replacement operation is carried out after the human hip joint is damaged or diseased, and the metal acetabulum outer cup is implanted into a patient body to restore the physiological function of the hip joint to a certain extent, relieve pain, improve the motion requirement of the patient and improve the life quality.

The conventional similar metal acetabular outer cup is manufactured by adopting an open die forging process, large burrs are generated in the forging process, the burrs need to be removed later through the processes of laser trimming, burr milling and the like, the processes are complicated, the manufacturing period is long, raw materials are consumed greatly, the material utilization rate is low, the filling defect is easy to generate, the inner spherical surface and the outer spherical surface of the acetabular outer cup are easy to generate the dislocation phenomenon when open die forging is adopted, the difficulty of forging equipment adjustment is increased, a special dislocation detection tool is required to be designed for detecting the dislocation quantity, the input cost of a tool measuring tool is increased, a workpiece is unqualified when the dislocation quantity is large, waste is generated, and the production cost is high.

Disclosure of Invention

The invention provides a closed forging die and a forging method for a metal acetabular outer cup, aiming at the technical problems that the existing metal acetabular outer cup is manufactured by adopting an open die forging process, the process is complicated, the manufacturing period is long, the material utilization rate is low, the mold filling defect is easy to generate, the adjustment difficulty of forging equipment is high, and the production cost is high.

The technical scheme is as follows:

the utility model provides a metal acetabular bone outer cup closed forging mould which characterized in that: the acetabulum outer cup comprises a punch and a female die, wherein a through die cavity is formed in the female die, the die cavity comprises a guide cylinder, a die cavity and an extrusion opening which are sequentially and coaxially communicated from top to bottom, and the shape of the die cavity is adapted to the shape of the acetabulum outer cup; the bottom surface of the punch is provided with a guide part and a forming part which are coaxially arranged from top to bottom, the guide part is in clearance fit with the guide cylinder, and the forming part is adaptive to the inner shape of the acetabulum outer cup.

It is further characterized in that:

and a chamfer is machined at the top of the guide cylinder along the circumferential direction.

The fit clearance between the guide part and the guide cylinder is 0.1 mm-0.5 mm of a single surface.

The guide draft angle of the female die is 0.1-1 degrees.

The height of the guide cylinder is 20 mm-40 mm.

The diameter of the extrusion opening is 3 mm-15 mm, and the length is 5 mm-30 mm.

A closed forging method for a metal acetabulum outer cup is characterized by comprising the following steps:

step 1, blanking, namely calculating the length and the diameter of a required bar according to the volume of an acetabulum outer cup, blanking the medical titanium alloy bar, and chamfering the upper end surface and the lower end surface of the bar, wherein the radius of the fillet is 3 mm-10 mm to finish blanking;

step 2, spraying, namely spraying an anti-oxidation coating on the surface of the bar;

and 3, final forging forming, namely mounting the forging die on an electric screw press, putting the bar stock in the step 2 into an electric furnace, heating to the titanium alloy forging process temperature to completely heat the bar stock, and transferring the bar stock into the forging die for final forging forming to obtain a final forged piece.

It is further characterized in that:

the process for spraying the anti-oxidation coating in the step 2 is to directly spray the glass-ceramic anti-oxidation coating after heating the bar stock to 150-250 ℃, wherein the thickness of the coating is 0.02-0.20 mm.

And 3, putting the bar stock into an electric furnace to be heated to 900-970 ℃ in the step 3, keeping the temperature for 10-30 min, taking out and immediately putting the bar stock into the female die sprayed with the die lubricant in advance to carry out finish forging forming.

The preset thermal expansion coefficients of the die cavity and the punch are 1.0-1.1.

The invention has the beneficial effects that:

1. the closed forging die comprises the punch and the female die, wherein the die cavity of the female die comprises the guide cylinder and the die cavity adaptive to the shape of the outer acetabular cup from top to bottom, and the bottom surface of the punch is provided with the guide part in clearance fit with the guide cylinder and the forming part adaptive to the inner shape of the outer acetabular cup from top to bottom, so that closed forging forming of the outer acetabular cup can be realized, no flash and filling defects are generated, the flash removing step can be omitted, the manufacturing period is shortened, the production efficiency is improved, raw materials are saved, and the material utilization rate is improved; the cooperation of the guide cylinder and the guide part can also accurately guide the forging process, ensure that the offset of the inner spherical surface and the outer spherical surface of the acetabulum outer cup meets the design requirement, ensure the product percent of pass, ensure simple adjustment of forging equipment and save the input cost of an offset detection tool;

2. the forging method adopts a closed forging process, can forge and form the acetabular outer cup only by blanking, spraying and finish forging, namely forge and form the acetabular outer cup by one-step forging, has simple forging process, does not generate flash and filling defects under the guarantee of a forging die, and has the advantages of short manufacturing period, high production efficiency, high utilization rate of forging materials, low investment cost of a tool clamp and the like.

Drawings

FIG. 1 is a front cross-sectional view of a forging die of the present invention;

FIG. 2 is an enlarged view of area A of FIG. 1;

FIG. 3 is a front view of a blanked bar stock in a forging method of the present invention;

FIG. 4 is a front cross-sectional view of a finish forge for an acetabular cup forged using the method of the invention.

Detailed Description

The closed forging die for the metal acetabular outer cup comprises a punch 1 and a female die 2, wherein the female die 2 is provided with a vertically through die cavity, the die cavity comprises a guide cylinder 3, a cavity 4 and an extrusion opening 5 which are sequentially and coaxially communicated from top to bottom, a chamfer 6 is machined in the circumferential direction of the top of the guide cylinder 3, the height of the guide cylinder 3 is 20 mm-40 mm, a guide drawing angle α (namely an included angle between the side wall of the guide cylinder and the vertical direction) of the female die 2 is 0.1-1 degrees, the shape of the cavity 4 is adaptive to the shape of the acetabular outer cup, the diameter of the extrusion opening 5 is 3 mm-15 mm, the length of the extrusion opening is 5 mm-30 mm, a guide part 7 and a forming part 8 which are coaxially arranged from top to bottom are arranged on the bottom surface of the punch 1, the guide part 7 is in clearance fit with the guide cylinder 3, the fit clearance is 0.1 mm-0.5 mm, the shape of the forming part 8 is adaptive to the inner shape of the acetabular outer cup, the outer cup is communicated with an external material ejecting mechanism 9 through the extrusion opening, the final material-ejecting mechanism is convenient to eject a workpiece through the guide drawing mechanism, and the guide drawing mechanism is convenient to eject the acetabular outer cup after finishing punch 3 and the guide drawing part α is designed.

Referring to fig. 1 to 4, the invention relates to a closed forging method of a metal acetabular outer cup, which comprises the following steps:

step 1, blanking, namely calculating the length and the diameter of a required bar 10 according to the volume of an acetabulum outer cup, blanking the medical titanium alloy bar, and chamfering the upper end surface and the lower end surface of the bar 10, wherein the radius R1 of the fillet of the upper end surface is =3 mm-10 mm, and the radius R2 of the fillet of the lower end surface is =3 mm-10 mm, so as to finish blanking;

step 2, spraying, namely heating the bar stock to 150-250 ℃, and then directly spraying a glass-ceramic anti-oxidation coating, wherein the thickness of the coating is 0.02-0.20 mm;

and 3, final forging forming, namely installing the forging die on an electric screw press, placing the bar in the step 2 in an electric furnace, heating to a titanium alloy forging process temperature, and keeping the temperature for a certain time to ensure that the bar is thoroughly heated, taking Ti6Al4V alloy as an example, the forging process temperature is 900-970 ℃ (namely heating to 40-60 ℃ below the phase transition temperature of Ti6Al4V alloy β), keeping the temperature for 10-30 min, taking out, immediately placing into a female die sprayed with die lubricant (usually graphite is used as the die lubricant), and performing final forging forming to obtain a final forging piece 11, wherein the forging direction is downward along the axis of a die cavity, and the preset thermal expansion coefficients of the die cavity and a punch are 1.0-1.1 in order to ensure the shape and the size of the final forging piece.

Fig. 4 is a schematic view of the finish forging configuration, and it can be seen that the finish forging 11 is flash-free, with only a longitudinal burr 12 formed at the top and a pinch-off heel 13 formed at the bottom, which can be removed in a post-finishing step (open forging also has a finishing step after flash removal). In addition, in the process of finish forging debugging, the condition of finish forging filling can be preliminarily judged only according to the formation conditions of longitudinal burrs and extrusion port tails, and the open forging has flash, so that the condition of finish forging filling is difficult to judge in the step of finish forging debugging, and the testing aid is needed.

The forging method of the present invention will be described in detail with reference to specific examples.

Example 1

Step 1, blanking, namely blanking a phi 35mm medical Ti6Al4V alloy bar, accurately calculating the length of the bar according to the volume of an acetabulum outer cup, and chamfering the upper end face and the lower end face of the bar, wherein the radius R1=3mm of the fillet of the upper end face and the radius R2=10mm of the fillet of the lower end face to finish blanking;

step 2, spraying, namely heating the bar stock to 150 ℃, and then directly spraying a glass-ceramic anti-oxidation coating, wherein the thickness of the coating is 0.02 mm;

and 3, final forging forming, namely mounting the forging die on an electric screw press, wherein the preset thermal expansion coefficient of a die cavity and a punch of the forging die is 1.0-1.1, putting the bar material in the step 2 into an electric furnace, heating to 900 ℃, keeping the temperature for 30min, taking out, immediately putting into a female die sprayed with graphite in advance, and performing final forging forming to obtain a final forging piece, wherein the forging direction is downward along the axis of the die cavity.

The mechanical property of the finish forging piece manufactured by the embodiment is detected, the result is shown in table 1, and it can be seen that the mechanical property is obviously higher than the design requirement, and the metal acetabular outer cup closed forging method is proved to be feasible and effective.

Example 2

Step 1, blanking, namely blanking a phi 45mm medical Ti6Al4V alloy bar, accurately calculating the length of the bar according to the volume of an acetabulum outer cup, and chamfering the upper end surface and the lower end surface of the bar, wherein the radius R1=5mm of the fillet of the upper end surface and the radius R2=8mm of the fillet of the lower end surface to finish blanking;

step 2, spraying, namely heating the bar stock to 200 ℃, and then directly spraying a glass-ceramic anti-oxidation coating, wherein the thickness of the coating is 0.11 mm;

and 3, final forging forming, namely mounting the forging die on an electric screw press, wherein the preset thermal expansion coefficient of a die cavity and a punch of the forging die is 1.0-1.1, heating the bar material in the step 2 in an electric furnace to 935 ℃, keeping the temperature for 20min, taking out the bar material, immediately putting the bar material into a female die sprayed with graphite in advance, and performing final forging forming to obtain a final forging piece, wherein the forging direction is downward along the axis of the die cavity.

The mechanical property of the finish forging piece manufactured by the embodiment is detected, the result is shown in table 1, and it can be seen that the mechanical property is obviously higher than the design requirement, and the metal acetabular outer cup closed forging method is proved to be feasible and effective.

Example 3

Step 1, blanking, namely blanking a phi 40mm medical Ti6Al4V alloy bar, accurately calculating the length of the bar according to the volume of an acetabulum outer cup, and chamfering the upper end face and the lower end face of the bar, wherein the radius R1=10mm of the fillet of the upper end face and the radius R2=10mm of the fillet of the lower end face to finish blanking;

step 2, spraying, namely heating the bar stock to 250 ℃, and then directly spraying a glass-ceramic anti-oxidation coating, wherein the thickness of the coating is 0.20 mm;

and 3, final forging forming, namely mounting the forging die on an electric screw press, wherein the preset thermal expansion coefficient of a die cavity and a punch of the forging die is 1.0-1.1, heating the bar material in the step 2 in an electric furnace to 970 ℃, keeping the temperature for 10min, taking out the bar material, immediately putting the bar material into a female die sprayed with graphite in advance, and performing final forging forming to obtain a final forging piece, wherein the forging direction is downward along the axis of the die cavity.

The mechanical property of the finish forging piece manufactured by the embodiment is detected, the result is shown in table 1, and it can be seen that the mechanical property is obviously higher than the design requirement, and the metal acetabular outer cup closed forging method is proved to be feasible and effective.

TABLE 1 mechanical Properties of acetabular cups prepared according to embodiments of the method of the invention

Claims (10)

1. The utility model provides a metal acetabular bone outer cup closed forging mould which characterized in that: the acetabulum outer cup comprises a punch and a female die, wherein a through die cavity is formed in the female die, the die cavity comprises a guide cylinder, a die cavity and an extrusion opening which are sequentially and coaxially communicated from top to bottom, and the shape of the die cavity is adapted to the shape of the acetabulum outer cup; the bottom surface of the punch is provided with a guide part and a forming part which are coaxially arranged from top to bottom, the guide part is in clearance fit with the guide cylinder, and the forming part is adaptive to the inner shape of the acetabulum outer cup.
2. The closed forging die for the metal acetabular outer cup as claimed in claim 1, wherein: and a chamfer is machined at the top of the guide cylinder along the circumferential direction.
3. The closed forging die for the metal acetabular outer cup as claimed in claim 1, wherein: the fit clearance between the guide part and the guide cylinder is 0.1 mm-0.5 mm of a single surface.
4. The closed forging die for the metal acetabular outer cup as claimed in claim 3, wherein: the guide draft angle of the female die is 0.1-1 degrees.
5. The closed forging die for the metal acetabular outer cup as claimed in claim 1, wherein: the height of the guide cylinder is 20 mm-40 mm.
6. The closed forging die for the metal acetabular outer cup as claimed in claim 1, wherein: the diameter of the extrusion opening is 3 mm-15 mm, and the length is 5 mm-30 mm.
7. A closed forging method of a metal acetabulum outer cup is characterized by comprising the following steps: which comprises the following steps:
step 1, blanking, namely calculating the length and the diameter of a required bar according to the volume of an acetabulum outer cup, blanking the medical titanium alloy bar, and chamfering the upper end surface and the lower end surface of the bar, wherein the radius of the fillet is 3 mm-10 mm to finish blanking;
step 2, spraying, namely spraying an anti-oxidation coating on the surface of the bar;
and 3, finish forging and forming, namely mounting the forging die of any one of claims 1 to 6 on an electric screw press, putting the bar stock in the step 2 into an electric furnace, heating to the titanium alloy forging process temperature to completely heat the bar stock, and transferring the bar stock into the forging die for finish forging and forming to obtain a finished forged piece.
8. The closed forging method for the metal acetabular outer cup according to claim 7, wherein: the process for spraying the anti-oxidation coating in the step 2 is to directly spray the glass-ceramic anti-oxidation coating after heating the bar stock to 150-250 ℃, wherein the thickness of the coating is 0.02-0.20 mm.
9. The closed forging method for the metal acetabular outer cup according to claim 7, wherein: and 3, putting the bar stock into an electric furnace to be heated to 900-970 ℃ in the step 3, keeping the temperature for 10-30 min, taking out and immediately putting the bar stock into the female die sprayed with the die lubricant in advance to carry out finish forging forming.
10. The closed forging method for the metal acetabular outer cup according to claim 7, wherein: the preset thermal expansion coefficients of the die cavity and the punch are 1.0-1.1.
CN201911219089.XA 2019-12-03 2019-12-03 Closed forging die and method for metal acetabular outer cup CN110899594A (en)

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Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2039608U (en) * 1988-07-30 1989-06-21 鼓宏发 Closed forging die of auto-removing excess stuff
CN2316068Y (en) * 1997-08-21 1999-04-28 湖北传动轴股份有限公司 Automobile generator claw-pole blank finish forging die
CN2772679Y (en) * 2005-01-05 2006-04-19 东风锻造有限公司 Closed forging mould of disk piece
CN101543874A (en) * 2009-04-29 2009-09-30 齐齐哈尔轨道交通装备有限责任公司 Die forging method based on screw press
CN101972835A (en) * 2010-09-10 2011-02-16 湖北三环锻造有限公司 Closed forging technique for steering knuckle
CN102240763A (en) * 2011-04-16 2011-11-16 湖北三环锻造有限公司 Medium-heavy automobile flange die forging process and punching and calibrating composite die thereof
CN202105960U (en) * 2011-06-09 2012-01-11 重庆新兴齿轮有限公司 Flash-free closed forging die
CN202263881U (en) * 2011-10-30 2012-06-06 东风锻造有限公司 Forging die
CN102873240A (en) * 2012-09-27 2013-01-16 许昌中兴锻造有限公司 Non-flash forging process for middle flanges of transmission shafts
CN103252434A (en) * 2013-04-24 2013-08-21 安徽铖友汽车零部件制造有限公司 Forging technology of bell housing
CN203304469U (en) * 2013-06-04 2013-11-27 望城县乌山联祥重型锻造有限公司 Deep-hole spindle nose precision forging die
CN103934397A (en) * 2014-05-14 2014-07-23 上海驳原金属材料有限公司 Engine turbine disc optimizing manufacturing process and device based on heat-resisting alloy
CN110369654A (en) * 2019-08-08 2019-10-25 无锡航亚科技股份有限公司 A kind of forging method of titanium alloy tibial plateau prosthetic joint implants

Patent Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2039608U (en) * 1988-07-30 1989-06-21 鼓宏发 Closed forging die of auto-removing excess stuff
CN2316068Y (en) * 1997-08-21 1999-04-28 湖北传动轴股份有限公司 Automobile generator claw-pole blank finish forging die
CN2772679Y (en) * 2005-01-05 2006-04-19 东风锻造有限公司 Closed forging mould of disk piece
CN101543874A (en) * 2009-04-29 2009-09-30 齐齐哈尔轨道交通装备有限责任公司 Die forging method based on screw press
CN101972835A (en) * 2010-09-10 2011-02-16 湖北三环锻造有限公司 Closed forging technique for steering knuckle
CN102240763A (en) * 2011-04-16 2011-11-16 湖北三环锻造有限公司 Medium-heavy automobile flange die forging process and punching and calibrating composite die thereof
CN202105960U (en) * 2011-06-09 2012-01-11 重庆新兴齿轮有限公司 Flash-free closed forging die
CN202263881U (en) * 2011-10-30 2012-06-06 东风锻造有限公司 Forging die
CN102873240A (en) * 2012-09-27 2013-01-16 许昌中兴锻造有限公司 Non-flash forging process for middle flanges of transmission shafts
CN103252434A (en) * 2013-04-24 2013-08-21 安徽铖友汽车零部件制造有限公司 Forging technology of bell housing
CN203304469U (en) * 2013-06-04 2013-11-27 望城县乌山联祥重型锻造有限公司 Deep-hole spindle nose precision forging die
CN103934397A (en) * 2014-05-14 2014-07-23 上海驳原金属材料有限公司 Engine turbine disc optimizing manufacturing process and device based on heat-resisting alloy
CN110369654A (en) * 2019-08-08 2019-10-25 无锡航亚科技股份有限公司 A kind of forging method of titanium alloy tibial plateau prosthetic joint implants

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