CN216461479U - Interlocking structure of upper and lower middle dies of upsetting crankshaft crank throw - Google Patents

Abstract

The utility model discloses an interlocking structure of an upper die and a lower die of a crank throw of an upsetting crankshaft, wherein a boss is arranged on the upper die of the crank throw, a groove is arranged on the lower die of the crank throw, and the boss corresponds to the groove; the method is characterized in that: the circular bead of the boss is provided with a second boss, the groove shoulder of the groove is provided with a second groove, the second boss is perpendicular to the boss in the length direction, and the second groove is perpendicular to the groove in the length direction. The utility model has the advantages that: the deformation resistance generated in the forging process acting on the surface of the die type groove can be distributed in a balanced manner, the forging forming force borne by the die with large stress is reduced, the deformation degree generated after the die is used can be reduced, the die is prevented from being frequently broken, the service life of the die is prolonged, the service cycle of the die is prolonged, the purpose of reducing the number of times of die renovation is achieved, the cost of the die is reduced, and the saving effect is obvious.

Description

Interlocking structure of upper and lower middle dies of upsetting crankshaft crank throw

Technical Field

The utility model relates to the field of machinery, in particular to a die, and more particularly relates to a die structure for an upper middle die and a lower middle die of a large-scale crankshaft upsetting crank throw.

Background

The upsetting forging technology for crankshaft is a production method of forging each crank throw separately by changing its mould, local heating and local upsetting. And after the die changing, the local heating and the local upsetting are centralized and unified for each batch of forgings, the same crank throw is produced, then the die changing, the local heating and the local upsetting are centralized and unified for the next same crank throw, and the forging production of the batch of forgings of each crank throw and the flange of the large-scale crankshaft is completed after the die changing, the local heating and the local upsetting are performed in multiple batches.

The design profiles of all crank throws of a forging blank in the general forging production process are completely the same, the same forging forming die is adopted for forging, the crank throw forming die does not need to be replaced unless the special use working condition of the crankshaft determines that the designed individual crank throw of the crankshaft is different from other normal crank throws, and an upper middle die, a lower middle die and a related die of the crank throw need to be manufactured separately and replaced. Because the crank throw spatial distribution angles and positions of the crankshaft are different, and the blank of the forging stock needs to be positioned in the length direction through the respective dies on the left side and the right side, the blank of the forging stock in a non-heating area is clamped, the high-temperature heated deformed metal is limited to finish forging in the grooves of the upper middle die, the lower middle die, the left first die and the right first die of the crank throw to form a local upsetting crank throw forging stock, and after each upsetting of the same batch of crank throw forging stocks at the same position, part of the dies need to be replaced, and then the local heating and local upsetting of the same batch of crank throw forging stocks at the same position are carried out.

The forging blank crank throw completes the forging forming deformation in the die groove under the high temperature state, especially in the forming deformation end period, the extremely large forging forming deformation force is needed, when upsetting forging is formed each time, the forces act on all directions of the die groove, along with the accumulation of the using times of the die, the stress of the die can generate deformation at the weak part of the die, the deformation is accumulated to a certain degree, the die fracture can occur to cause the die scrap, the service life of the die is short, and in the forging forming process, the abnormal forging forming forging blank is caused by the die fracture, the unqualified forging piece geometric dimension is formed, and the forging piece scrap can be caused seriously. Although the mold is prevented from being deformed and broken and scrapped by controlling the use times of the mold and determining the mold renovating period, the frequency of renovating the mold is high, and more mold renovating cost is generated.

The existing mold structure is shown in fig. 1-4, the shoulder 21 is a plane, and the groove shoulder 31 is also a plane, so that when the metal on the two sides and the metal in the middle move along the arrow direction of fig. 1, the mold cavity 8 is easily deformed and cracked under the influence of the bending moment of the metal deformation resistance.

SUMMERY OF THE UTILITY MODEL

In order to solve the technical problems, the utility model aims to provide an interlocking structure of an upper die and a lower die of an upsetting crankshaft crank throw, which comprises an upper die and a lower die of the crank throw, a left upper die, a left lower die, a right upper die and a right lower die, wherein the left upper die and the left lower die are buckled up and down, and the right upper die and the right lower die are buckled up and down; the forging stock forming area is arranged between the upper middle die and the lower middle die of the crank throw; the upper middle die of the crank throw is provided with a boss, the lower middle die of the crank throw is provided with a groove, and the boss corresponds to the groove; the shoulder of boss department sets up the second boss, the groove shoulder department of recess sets up the second recess, the second boss with the length direction mutually perpendicular of boss, the second recess with the length direction mutually perpendicular of recess.

The included angle between the second boss and the crank throw middle die in the vertical direction is 5-7 degrees, and the included angle between the second groove and the crank throw middle die in the vertical direction is 5-7 degrees.

The length of the second boss is 1/3 of the length of the middle die on the crank throw, and the length of the second groove is 1/3 of the length of the middle die on the crank throw.

The second boss is arranged in the middle of the shoulder, and the second groove is arranged in the middle of the groove shoulder.

The utility model has the advantages that: the deformation resistance generated in the forging process acting on the surface of the die type groove can be distributed in a balanced manner, the forging forming force borne by the die with large stress is reduced, the deformation degree generated after the die is used can be reduced, the die is prevented from being frequently broken, the service life of the die is prolonged, the service cycle of the die is prolonged, the purpose of reducing the number of times of die renovation is achieved, the cost of the die is reduced, and the saving effect is obvious.

Drawings

FIG. 1 is a schematic diagram of a prior art structure;

FIG. 2 is an exploded view of FIG. 1;

FIG. 3 is a schematic view of a prior art construction of a bell crank upper intermediate die;

FIG. 4 is a schematic view of a prior art bell crank lower intermediate die configuration;

FIG. 5 is a schematic view of the structure of the middle mold of the bell crank of the present invention;

FIG. 6 is a schematic view of the construction of the lower middle mold of the bell crank of the present invention;

FIG. 7 is a schematic view of the mold under force.

Detailed Description

The present invention will be described in detail with reference to the accompanying drawings, and as shown in the drawings, the present invention is constituted by 4 second bosses 23 of the upper middle die of the bell crank and 4 second recesses 33 of the lower middle die of the bell crank,

the second boss is arranged on the shoulder 22 and the second groove is arranged on the groove shoulder 32; the second boss 23 is perpendicular to the boss 21 and respectively extends along the axial direction and the radial direction of the forging stock; the second groove 33 and the groove 31 are perpendicular to each other and are respectively arranged along the axial direction and the radial direction of the forging stock; the second boss 23 corresponds to the second groove 33; the included angle between the side walls of the second boss 23 and the second groove 33 and the vertical direction of the crank middle die is 5-7 degrees, so that the interference of the die opening and closing processes of the second boss and the second groove is avoided, and the interlocking purpose is achieved. The length of the second boss and the second groove is equal to 1/3 of the length of the flat plane of the upper and lower crank middle dies, the center of the second boss and the second groove is positioned on the flat plane 1/2, and the width of the second boss and the second groove is equal to the width of the convex-concave structure of the die, so that the maximum structural strength can be ensured.

Taking the forging process of the No. 4 crank throw of the upset crankshaft as an example, the description is as follows: the crankshaft locally heats the 4 th crank throw blank (the forging blank 1 in figure 2), the blank is loaded into a die of an upsetting tool, the die comprises a plurality of combined dies of a left upper die 4, a plurality of combined dies of a right upper die 5, a plurality of combined dies of a left lower die 6, a plurality of combined dies of a right lower die 7, a crank throw upper middle die 2 and a crank throw lower middle die 3, after die assembly, the left and right upper and lower combined dies clamp the forging blank, when upsetting and upsetting are performed by forging towards the crank throw middle die direction in opposite directions, the crank throw upper middle die and the crank throw lower middle die clamp a connecting rod ring groove journal in the middle of a local heating area of the forging blank, the crank throw upper middle die pushes the blank and the crank throw lower middle die to perform bending and upsetting vertically and downwards, the forging motions in two directions are performed in the same time period, until the left and right side dies and upper middle dies and lower middle dies contact the crank throw lower die and the crank throw lower die reach the lower dead center of the upsetting tool, upsetting forging forming is completed, the crankshaft heats the 4 th crank throw blank to form a forged blank of the 4 th crank throw 101 after local multi-directional forging; during the upsetting forming process of the forging blank 1, particularly at the final forming stage, metal flash appears on the forging blank, at the moment, a press is required to output extremely large forging forming force to promote the forging blank to be formed and deformed, the forging force needs to be borne by each die, the bearing force simultaneously transmits the forging force to an upsetting tool and a press body, particularly the upsetting contour direction of upper and lower crank middle dies, and the normal direction upsetting forming force (such as the arrow direction of fig. 7) borne by the upper and lower crank middle dies only needs to be borne by the side walls of the die. The structure and rigidity of the upper middle die of the crank throw are better than those of the lower middle die of the crank throw. If the structure of the utility model is not adopted, the lower middle die of the crank throw can deform and widen in the width direction of the profile of the forged crank throw after being used for many times, so that formed metal is insufficient and can be scrapped seriously. With the increase of the production and use times of the die, the deformation of the die is accumulated little by little, and finally the die is broken at the weak section position of the die, and when the die is broken, the produced crank throw forging process has no die groove to control the metal deformation, so that the appearance of the forge piece is abnormal, and the forge piece which is seriously abnormal can only be scrapped.

The middle mould passes through 4 second bosss and the cooperation of second recess compound die under the middle mould on the crank throw of this example and the crank throw, realize the interlocking of middle mould width direction about the crank throw, can decompose the mould profile groove normal direction forming force and transmit to the little mould of atress on like this effectively, reach the purpose of the balanced off-load forging forming force of mould, reduce the deformation that weak structure mould in use took place, improve mould life, the effective control mould fracture frequency takes place, avoid forging waste product output, the saving effect is showing.

Claims (4)

1. An interlocking structure of an upper die and a lower die of an upsetting crankshaft crank throw comprises an upper die of the crank throw, a lower die of the crank throw, a left upper die, a left lower die, a right upper die and a right lower die, wherein the left upper die and the left lower die are buckled up and down, and the right upper die and the right lower die are buckled up and down; the forging stock forming area is arranged between the upper middle die and the lower middle die of the crank throw; the upper middle die of the crank throw is provided with a boss, the lower middle die of the crank throw is provided with a groove, and the boss corresponds to the groove; the method is characterized in that: the shoulder of boss department sets up the second boss, the groove shoulder department of recess sets up the second recess, the second boss with the length direction mutually perpendicular of boss, the second recess with the length direction mutually perpendicular of recess.

2. The interlocking structure of the upper and lower middle dies of the upset crankshaft bell crank of claim 1, characterized in that: the included angle between the second boss and the crank throw middle die in the vertical direction is 5-7 degrees, and the included angle between the second groove and the crank throw middle die in the vertical direction is 5-7 degrees.

3. The interlocking structure of the upper and lower middle dies of the upset crankshaft bell crank of claim 1, characterized in that: the length of the second boss is 1/3 of the length of the middle die on the crank throw, and the length of the second groove is 1/3 of the length of the middle die on the crank throw.

4. The interlocking structure of the upper and lower middle dies of the upset crankshaft bell crank of claim 1, characterized in that: the second boss is arranged in the middle of the shoulder, and the second groove is arranged in the middle of the groove shoulder.

Images