CN116274785A - Method for forming crank turning neck arc surface and inclined surface - Google Patents
Method for forming crank turning neck arc surface and inclined surface Download PDFInfo
- Publication number
- CN116274785A CN116274785A CN202310088864.2A CN202310088864A CN116274785A CN 116274785 A CN116274785 A CN 116274785A CN 202310088864 A CN202310088864 A CN 202310088864A CN 116274785 A CN116274785 A CN 116274785A
- Authority
- CN
- China
- Prior art keywords
- crank
- shaped
- blank
- anvil
- arc surface
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21J—FORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
- B21J5/00—Methods for forging, hammering, or pressing; Special equipment or accessories therefor
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21J—FORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
- B21J1/00—Preparing metal stock or similar ancillary operations prior, during or post forging, e.g. heating or cooling
- B21J1/06—Heating or cooling methods or arrangements specially adapted for performing forging or pressing operations
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21J—FORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
- B21J5/00—Methods for forging, hammering, or pressing; Special equipment or accessories therefor
- B21J5/02—Die forging; Trimming by making use of special dies ; Punching during forging
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21J—FORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
- B21J5/00—Methods for forging, hammering, or pressing; Special equipment or accessories therefor
- B21J5/06—Methods for forging, hammering, or pressing; Special equipment or accessories therefor for performing particular operations
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Forging (AREA)
Abstract
The invention relates to a method for forming a crank turning neck arc surface and an inclined surface, which comprises the steps of putting a hexagonal prism blank into a U-shaped anvil, pressing the hexagonal prism blank by a flat anvil in a descending manner of a press, and forming the hexagonal prism blank into a U-shaped blank in the U-shaped anvil; after the U-shaped blank is formed, the U-shaped anvil is replaced by a V-shaped convex anvil, the arc surface of the U-shaped blank is contacted with the trapezoid boss of the V-shaped convex anvil, and the plane of the flat anvil pressing U-shaped blank forms inclined planes at two sides of the crank forging; after the inclined planes at two sides of the crank forging are pressed, the V-shaped convex anvil is replaced by a flat anvil, and then the flat anvil is used for pressing out the crank arms at two sides, so as to form a crank blank with the crank arms at two sides. The shaping of the crank neck end part of the crank for the high-horsepower low-speed diesel engine crankshaft is ensured, so that the shape of the crank neck end part is more similar to the finish machining shape, the end part and the crank neck quality of the crank are greatly improved, and the raw material cost of the crank is greatly reduced; in addition, the crank blanks with different specifications only need to be replaced by different U-shaped anvils, and the V-shaped convex anvils can be shared, so that the die cost is reduced.
Description
Technical Field
The invention belongs to the technical field of crank forming for a marine low-speed diesel engine, and particularly relates to a method for forming an arc surface and an inclined surface of a crank turning neck.
Background
The crankshaft of the marine low-speed diesel engine is usually semi-combined in structure and is formed by combining a crank, a main journal in the middle, output ends distributed at two ends and a free end jacket. Among the several components of the crankshaft of the marine low-speed diesel engine, the number of the cranks is the largest, the weight is the largest, the structure is the most complex, the forming precision requirement is strict, the manufacturing difficulty is the largest, the forming quality of the cranks directly influences the comprehensive mechanical property of the crankshaft, the manufacturing cost of the cranks is also determined, and the survival of manufacturing enterprises is further influenced, so the manufacturing level of the cranks determines the manufacturing level of the crankshaft of the low-speed engine.
The crank is usually formed by adopting a bending forging method, namely, after a blank with a boss in the middle is forged, the blank is bent and formed on a die, and the shape of the bent crank is determined by the shape of the blank, so that the blank making process is the most critical link in the crank forging process.
The crank neck part of the crank consists of an arc on one side surface and an inclined surface on the other side surface, the arc and the inclined surface are difficult to form, the end part of the crank neck is integrally forged into a big square in the original blank manufacturing process, and the crank blank is in the shape of a big square boss in the middle and wings on two sides. The forging method of the blank is the simplest, but the forging method of the large square block causes great waste of raw materials; in addition, the arc and the inclined plane at the end part of the turning neck are subjected to subsequent machining, and the quality of the turning neck is poorer than that of the whole forming.
Disclosure of Invention
The invention aims to overcome the defects and aims to provide a method for forming the arc surface and the inclined surface of the crank turning neck, so that the forming of the crank turning neck end is closer to the finish machining size of a product.
In order to achieve the above purpose, the invention provides a method for forming a crank journal arc surface and an inclined surface, which comprises the following steps:
putting the hexagonal prism blank into a U-shaped anvil, and pressing the hexagonal prism blank by using a flat anvil in a descending manner of a press, wherein the hexagonal prism blank is formed into a U-shaped blank in the U-shaped anvil, and the arc surface of the U-shaped blank is the arc surface of the end part of the turning neck;
after the U-shaped blank is formed, the U-shaped anvil is replaced by a V-shaped convex anvil, the arc surface of the U-shaped blank is contacted with the trapezoid boss of the V-shaped convex anvil, and the plane of the flat anvil pressing U-shaped blank forms inclined planes at two sides of the crank forging;
after the inclined planes at two sides of the crank forging are pressed, the V-shaped convex anvil is replaced by a flat anvil, and then the flat anvil is used for pressing out the crank arms at two sides, so as to form a crank blank with the crank arms at two sides.
Further, returning the crank blank with the crank arm to heat, placing the crank blank on a bending bracket after discharging, and undershooting from an open crotch of the crank blank by using a punching plate with a concave circular arc cavity to form a crank neck circular arc surface on the inner side surface of the open crotch; and (3) forming the crank neck when the arc punching plate continues to descend to the process size, wherein the crank arms at the two sides of the crank blank are V-shaped, and finally inserting the arc punching plate into a notch to form the crank forging piece by flattening the crank arms at the two sides on the press.
Further, the hexagonal prism blank is an irregular hexagonal prism, the width W of any group of parallel surfaces of the hexagonal prism is equal to the width of the crank forging, the height H of two vertexes facing each other of the group of parallel surfaces is equal to the length of the crank forging turning neck +550-650mm, and any one of the two vertexes is used for entering the U-shaped anvil 5.
Further, the inner cavity molded surface of the U-shaped anvil comprises a bottom arc surface, inclined surfaces which are inclined outwards at two ends of the bottom arc surface and a guide arc surface connected with the inclined surfaces, and the diameter of the arc surface is equal to the width of the crank forging; the maximum height of the inner cavity of the U-shaped anvil is larger than or equal to the length of the crank forging piece turning neck, and the thickness of the U-shaped anvil is the same as the width of the flat anvil.
Further, the maximum opening width of the U-shaped anvil is 180-220 mm larger than the width of the crank forging piece.
Further, the height of the U-shaped blank is equal to the length of the crank forging piece turning neck of +300-350 mm.
Further, the V-shaped convex anvil comprises a cuboid base and a trapezoid boss, the inclination of the inclined plane of the trapezoid boss is equal to that of the inclined plane of the end part of the crank forging turning neck, the height of the inclined plane of the trapezoid boss is equal to that of the inclined plane of the end part of the crank forging turning neck, and the width of the cuboid base is the same as that of the flat anvil.
Further, the specific process of forming inclined planes on two sides of the crank forging by the plane of the flat anvil U-shaped blank comprises the following steps: the flat anvil presses the plane of the U-shaped blank until the inclined plane formed by the U-shaped blank is flush with the inclined plane of the trapezoid boss; and according to the method, firstly forming an inclined plane at one side, and then pressing and forming an inclined plane at the other side of the crank blank crank neck end.
Compared with the prior art, the invention has the beneficial effects that: the invention adopts a two-step molding method to mold, ensures the molding of the appearance of the end part of the crank for the crank of the high-horsepower low-speed diesel engine, ensures that the appearance of the end part of the crank is more similar to the finish appearance, greatly improves the quality of the end part and the crank, and simultaneously greatly reduces the raw material cost of the crank; in addition, the crank blanks with different specifications only need to be replaced by different U-shaped anvils, and the V-shaped convex anvils can be shared, so that the die cost is reduced.
Drawings
FIG. 1 is a schematic view of a hexagonal blank structure according to the present invention;
FIG. 2 is a schematic illustration of a hexagonal prism blank of the present invention being inserted into a U-shaped anvil;
FIG. 3 is a schematic view of the U-shaped blank forming process of the present invention;
FIG. 4 is a schematic view of a V-shaped anvil U-shaped blank according to the present invention;
FIG. 5 is a schematic view of a crank blank with a crank arm of the present invention;
FIG. 6 is a schematic view of the crank blank of the present invention in a curved configuration;
FIG. 7 is a schematic view of a crank forging of the present invention bent to shape.
Detailed Description
According to the invention, two types of tools are adopted to form the arc surface 1 and the inclined surface 2 at the end part of the crank forging, and after the crank forging is formed, the formed crank forging is bent and formed. The method comprises the following steps:
the blank can be a hexagonal prism blank or an elliptic cylinder blank, and is obtained by performing primary upsetting and drawing forming on fully heated steel ingots. As shown in fig. 1, the hexagonal prism blank is an irregular hexagonal prism, the width W of any group of parallel surfaces of the hexagonal prism is equal to the width of the crank forging, the height H of two vertexes facing each other in the group is equal to the length +550-650mm of the crank neck of the crank forging, and any one of the two vertexes is used for entering the U-shaped anvil 5. The hexagonal prism blank can be easily placed into the U-shaped anvil 5, and the situation that the U-shaped anvil cannot be placed due to clamping cannot occur.
As shown in fig. 2, the inner cavity molded surface of the U-shaped anvil comprises a bottom arc surface, inclined surfaces which are inclined outwards at two ends of the bottom arc surface and a guide arc surface connected with the inclined surfaces, the diameter of the arc surface is equal to the width of the crank forging, and the width of the largest opening of the U-shaped anvil is 180-220 mm larger than the width of the crank forging, so that the demolding is convenient; the maximum height of the inner cavity of the U-shaped anvil 5 is larger than or equal to the length of the crank forging turning neck, and the thickness of the U-shaped anvil 5 is the same as the width of the flat anvil 4.
Putting the hexagonal prism blank into a U-shaped anvil 5, pressing the hexagonal prism blank by using a flat anvil 4 in a descending manner of a press, and gradually forming the hexagonal prism blank into a U-shaped blank in the U-shaped anvil 5, wherein the arc surface of the U-shaped blank is a crank end arc surface 1, as shown in fig. 3; the height of the U-shaped blank is equal to the length of the crank forging turning neck of +300-350 mm. After the U-shaped blank is formed, the lower U-shaped anvil 5 is replaced by a V-shaped convex anvil 3.
In combination with the illustration of fig. 4, the V-shaped convex anvil 3 is a tool for forming the inclined plane of the crank forging turning neck, the V-shaped convex anvil 3 comprises a cuboid base and a trapezoid boss, the inclined plane of the trapezoid boss is equal to the inclined plane of the crank forging turning neck end, and the inclined plane of the trapezoid boss is equal to the inclined plane of the crank forging turning neck end, and the width of the cuboid base is the same as the width of the flat anvil 4.
When the inclined plane of the U-shaped blank is pressed, the arc surface of the U-shaped blank is contacted with the trapezoid boss of the V-shaped convex anvil 3, and the flat anvil 4 presses the plane of the U-shaped blank until the inclined plane 2 formed by the U-shaped blank is flush with the inclined plane of the trapezoid boss, and the press goes upward. The inclined plane 2 on one side is gradually formed according to the method, and then the inclined plane 2 on the other side of the crank blank crank neck end is pressed.
After the inclined planes 2 on the two sides of the crank forging are pressed, the V-shaped convex anvil 3 is replaced by a flat anvil 4, and then the flat anvil 4 is used for pressing out the crank arms on the two sides, so as to form a crank blank with the crank arms on the two sides, as shown in figure 5.
Referring to fig. 6, the crank blank with the crank arm is returned to the furnace for full heating, the crank blank is placed on the bending bracket 8 after being discharged, the punching plate 7 with the concave arc cavity is used for punching downwards from the crotch of the crank blank, namely the symmetry axis, so as to form the crank neck arc surface 6 of the inner side surface of the crotch, and the crank neck arc surface 6 of the inner side surface of the crotch and the crank neck end arc surface 1 jointly form the whole arc of the crank neck. The arc punching plate continuously descends to the process size to form a crank neck, and crank arms on two sides of a crank blank are in a V shape, wherein the V-shaped angle is close to 60 degrees; finally, the circular arc tongue plate is inserted into the notch, the crank arms on two sides are flattened on the press, and the crank forging is finally formed, as shown in fig. 7.
The invention adopts a two-step molding method to mold, ensures the end part and the crank neck quality of the crank for the crank of the high-horsepower low-speed diesel engine, and greatly reduces the raw material cost of the crank; in addition, the shaping of turning neck tip appearance of different specifications makes the appearance of crank turning neck tip more be close to the finish machining appearance, improves the crank blank greatly and only need change different U type anvils, and V type convex anvil can share, reduces the mould cost.
Claims (8)
1. A method for forming a crank turning neck arc surface and an inclined surface is characterized by comprising the following steps of: the molding method comprises the following steps:
putting the hexagonal prism blank into a U-shaped anvil (5), pressing the hexagonal prism blank by using a flat anvil (4) in a downward direction of a press, and forming the hexagonal prism blank into a U-shaped blank in the U-shaped anvil (5), wherein the arc surface of the U-shaped blank is the arc surface (1) of the end part of the turning neck;
after the U-shaped blank is formed, the U-shaped anvil (5) is replaced by a V-shaped convex anvil (3), the arc surface of the U-shaped blank is contacted with the trapezoid boss of the V-shaped convex anvil (3), and the plane of the U-shaped blank is pressed by the flat anvil (4) to form inclined planes (2) on two sides of the crank forging;
after the inclined planes (2) on two sides of the crank forging are pressed, the V-shaped convex anvil (3) is replaced by the flat anvil (4), and then the crank arms on two sides are pressed out by the flat anvil (4) to form a crank blank with crank arms on two sides.
2. The method for forming the arc surface and the inclined surface of the crank connecting neck according to claim 1, wherein the method comprises the following steps: the crank blank with the crank arm is returned to the furnace for heating, the crank blank is placed on a bending bracket (8) after being discharged, and a punch plate (7) with a concave circular arc cavity is used for undershooting from an open crotch of the crank blank to form a crank neck circular arc surface (6) on the inner side surface of the open crotch; and (3) forming the crank neck when the arc punching plate continues to descend to the process size, wherein the crank arms at the two sides of the crank blank are V-shaped, and finally, inserting the arc punching plate into the open crotch, and flattening the crank arms at the two sides on the press to form the crank forging.
3. The method for forming the arc surface and the inclined surface of the crank connecting neck according to claim 1, wherein the method comprises the following steps: the hexagonal prism blank is an irregular hexagonal prism, the width W of any group of parallel surfaces of the hexagonal prism is equal to the width of the crank forging, the height H of two opposite vertexes of the group of parallel surfaces is equal to the length +550-650mm of the crank forging turning neck, and any one of the two vertexes is used for entering the U-shaped anvil (5).
4. The method for forming the arc surface and the inclined surface of the crank connecting neck according to claim 1, wherein the method comprises the following steps: the inner cavity molded surface of the U-shaped anvil comprises a bottom arc surface, inclined surfaces which are inclined outwards at two ends of the bottom arc surface and a guide arc surface connected with the inclined surfaces, and the diameter of the arc surface is equal to the width of the crank forging; the maximum height of the inner cavity of the U-shaped anvil (5) is larger than or equal to the length of the crank forging turning neck, and the thickness of the U-shaped anvil (5) is the same as the width of the flat anvil (4).
5. The method for forming the arc surface and the inclined surface of the crank connecting neck according to claim 4, wherein the method comprises the following steps: the width of the largest opening of the U-shaped anvil is 180-220 mm larger than the width of the crank forging piece.
6. The method for forming the arc surface and the inclined surface of the crank connecting neck according to claim 1, wherein the method comprises the following steps: the height of the U-shaped blank is equal to the length of the crank forging turning neck of +300-350 mm.
7. The method for forming the arc surface and the inclined surface of the crank connecting neck according to claim 1, wherein the method comprises the following steps: the V-shaped convex anvil (3) comprises a cuboid base and a trapezoid boss, the inclination of the inclined plane of the trapezoid boss is equal to that of the inclined plane of the end part of the crank forging turning neck, the height of the inclined plane of the trapezoid boss is equal to that of the inclined plane of the end part of the crank forging turning neck, and the width of the cuboid base is the same as that of the flat anvil (4).
8. The method for forming the arc surface and the inclined surface of the crank connecting neck according to claim 7, wherein the method comprises the following steps: the specific process of forming inclined planes (2) on two sides of a crank forging by pressing the plane of the U-shaped blank by the flat anvil (4) is as follows: the flat anvil (4) presses the plane of the U-shaped blank until the inclined plane (2) formed by the U-shaped blank is flush with the inclined plane of the trapezoid boss; and according to the method, firstly forming an inclined plane (2) on one side, and then pressing and forming the inclined plane (2) on the other side of the crank blank crank neck end.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310088864.2A CN116274785A (en) | 2023-02-09 | 2023-02-09 | Method for forming crank turning neck arc surface and inclined surface |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310088864.2A CN116274785A (en) | 2023-02-09 | 2023-02-09 | Method for forming crank turning neck arc surface and inclined surface |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116274785A true CN116274785A (en) | 2023-06-23 |
Family
ID=86795100
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310088864.2A Pending CN116274785A (en) | 2023-02-09 | 2023-02-09 | Method for forming crank turning neck arc surface and inclined surface |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116274785A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117139536A (en) * | 2023-11-01 | 2023-12-01 | 天津清研特锻技术有限公司 | Forging method for all-fiber bending upsetting combined crankshaft and crank forging |
-
2023
- 2023-02-09 CN CN202310088864.2A patent/CN116274785A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117139536A (en) * | 2023-11-01 | 2023-12-01 | 天津清研特锻技术有限公司 | Forging method for all-fiber bending upsetting combined crankshaft and crank forging |
| CN117139536B (en) * | 2023-11-01 | 2024-03-08 | 天津清研特锻技术有限公司 | Forging method for all-fiber bending upsetting combined crankshaft and crank forging |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113926973B (en) | Combined anvil die and process for forging large-scale crank throw | |
| CN109465368B (en) | Blank-making forming method for large-section-ratio complex-shape mutation shaft aluminum alloy forging | |
| KR101481200B1 (en) | Manufacturing device and method thereof for crank throw | |
| CN202539362U (en) | Small-angle conical part molding die | |
| CN116274785A (en) | Method for forming crank turning neck arc surface and inclined surface | |
| CN112846029A (en) | Front shaft bending preforming process adopting U-shaped widening preforming structure | |
| CN111604455A (en) | Steel piston forging die | |
| CN1046865A (en) | Automobile transmission shaft universal-joint fork extrusion forging process and mould thereof | |
| CN206276860U (en) | Marine diesel crank bends forging tools | |
| CN207013669U (en) | Forge fitting device in inclined-plane | |
| CN106583620A (en) | Crank bending forging tool and method of marine diesel engine | |
| CN211071645U (en) | Cold heading forming die assembly for passenger car engine oil delivery pipe bolt | |
| CN112676515B (en) | Die forging forming method and die for marine crank throw | |
| CN211276197U (en) | Mould for extruding heavy truck clutch cover mounting plane | |
| CN104624893B (en) | forging forming method of large marine crank | |
| CN107214283A (en) | The H profile steel manufacture mould of nuclear fusion stack magnet support | |
| CN208495682U (en) | Valve body forging mold | |
| CN110886756A (en) | Special-shaped eccentric pin column and production process thereof | |
| CN113245491A (en) | Crank die forging combined female die | |
| CN215199076U (en) | Adjusting device for crankshaft correction die of press | |
| CN206435708U (en) | Sunshine automobile net-size forging forging mold | |
| CN1548782A (en) | Method for producing cold forging wing-shaped screw nut | |
| CN211027943U (en) | Gear forging die | |
| CN218798853U (en) | Combined core mould for forging large crank inner cavity | |
| CN212643296U (en) | Connecting rod for forging special streamline on parting surface |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |