CN117300035A - A new type of crankshaft forging equipment and mold design method - Google Patents

Abstract

The invention discloses novel crankshaft forging equipment and a mold design method, wherein the novel crankshaft forging equipment comprises a mold, a positioning assembly and a bottom plate, and is characterized in that: the bottom plate is provided with two groups of symmetrical transverse grooves; the positioning assembly comprises symmetrical lead screw motors, sliding blocks on the lead screw motors are respectively and fixedly connected with positioning U-shaped clamping grooves, the positioning U-shaped clamping grooves are symmetrically matched with the die, transverse round rods are respectively arranged in the transverse grooves, each transverse round rod is respectively and fixedly connected with the bottom plate, transverse sliding blocks are respectively arranged in the transverse grooves, and each transverse round rod respectively penetrates through the corresponding transverse sliding block. The invention relates to the field of forging equipment, in particular to novel crankshaft forging equipment and a die design method. The invention aims to solve the technical problem of providing novel crankshaft forging equipment and a die design method, improving a die structure and eliminating the forging and folding defects of a crankshaft blank.

Description

Novel crankshaft forging equipment and die design method

Technical Field

The invention relates to the field of forging equipment, in particular to novel crankshaft forging equipment and a die design method.

Background

The crankshaft is a key core component of the engine, and is subjected to periodically-changed gas pressure and inertia force of reciprocating motion of the piston connecting rod group in the working process, and is easy to crack and break from parts with serious stress concentration such as transition fillets, crank arms and the like under the interaction of various complex alternating loads such as bending, torsion and vibration. The reliability of the crankshaft directly influences the reliability of the whole engine, and the failure of the crankshaft not only leads to the failure of the whole engine, but also can cause larger potential safety hazards in traffic, engineering and the like. When the crankshaft has defects such as cracks and folds, the crankshaft is extremely easy to break from the defect part in the using process.

A large number of forging and folding defects appear on different parts of a novel heavy-duty crankshaft blank such as a crank butterfly face, a crank arm, a connecting rod gear weight reducing groove, a big end face and a small end face, a large number of wastes are generated, and the reliability of a crankshaft is seriously affected.

The reason why the forging folding defect of the crankshaft blank occurs is mainly related to the design of the forging die.

The root cause of blank folding defect in the crankshaft forging process is analyzed, and the forging die design capable of avoiding the blank folding defect of the crankshaft is provided.

And (3) analyzing forging folding reasons of blanks:

(1) Analysis of folding defect cause of crank butterfly face

The die drawing angle of the upper die of the crank butterfly face of the crankshaft blank is 3 degrees, the die drawing angle is too small, and redundant metal bars are not beneficial to flowing to the flash in the forging process, so that the butterfly face is folded.

(2) Analysis of folding reason of crank arm

The crankshaft connecting rod neck blank pre-forging die cavity is smaller, the crank arm die cavity is wider, the material of the connecting rod neck part after pre-forging is less, the material of the crank arm part is more, and the redundant material of the crank arm part flows to the connecting rod neck die cavity rapidly during final forging, so that folding defects are easy to generate.

(3) Analysis of folding reason of connecting rod gear weight-reducing groove

The parting surface of the weight-reducing groove of the connecting rod gear of the crankshaft deviates to one side of the lower die of the die, the parting surface is too fluctuated, the design of the discharging area of the lower die of the pre-forging die is too high, the metal deformation of the weight-reducing groove part of the connecting rod gear in the pre-forging forming process is severe, the flowing speed of raw materials is too high, and folding defects are easy to form.

(4) Big and small head end surface folding reason analysis

Firstly, roll forging shrinkage can occur at the small end surface of a roll blank after roll forging, and end surface folding defects are easy to form during forging; secondly, the length of the original bar is insufficient or the distance between rollers is too large, so that the length of a roller blank after the roller forging is insufficient, and end face folding defects are easy to form during final forging.

Aiming at the current situation that a large number of forging folding defects occur, the traditional design thought needs to be changed, a novel crankshaft forging die is designed, the die structure is improved, the forging folding defects of a crankshaft blank are eliminated, and the blank qualification rate and the product reliability are improved.

Disclosure of Invention

The invention aims to solve the technical problem of providing novel crankshaft forging equipment and a die design method, improving a die structure and eliminating the forging and folding defects of a crankshaft blank.

The invention adopts the following technical scheme to realize the aim of the invention:

novel crankshaft forging equipment and mold design method, comprising a mold, a positioning assembly and a bottom plate, and is characterized in that: the bottom plate is provided with two groups of symmetrical transverse grooves; the positioning assembly comprises symmetrical screw motors, sliding blocks on the symmetrical screw motors are respectively and fixedly connected with positioning U-shaped clamping grooves, the symmetrical positioning U-shaped clamping grooves are matched with the die, transverse round rods are respectively arranged in each transverse groove, each transverse round rod is respectively and fixedly connected with the bottom plate, transverse sliding blocks are respectively arranged in each transverse groove, each transverse round rod respectively penetrates through the corresponding transverse sliding block, and each transverse sliding block is respectively and fixedly connected with the corresponding positioning U-shaped clamping groove; the die cavity of the die comprises a butterfly surface die drawing angle, a connecting rod neck cavity structure, a connecting rod gear weight reducing groove and a big and small head end surface cavity structure, wherein the butterfly surface die drawing angle, the connecting rod neck cavity structure, the connecting rod gear weight reducing groove and the big and small head end surface cavity structure are sequentially communicated.

As a further limitation of the technical scheme, the bottom plate is fixedly connected with the film pressing assembly, the film pressing assembly comprises a supporting guide rod, a group of supporting guide rods are respectively connected with the top plate, the top plate is fixedly connected with a group of hydraulic rods, and piston rods of the hydraulic rods are respectively connected with the pressing blocks.

As a further limitation of the present solution, a set of said guide rods passes through said press block.

As a further limitation of the technical scheme, the bottom plate is connected with the top block power assembly, the top block assembly comprises a motor, the bottom plate is fixedly connected with the motor, the bottom plate is provided with a longitudinal groove, an output shaft of the motor penetrates through the bottom plate to be connected with a screw rod, a longitudinal sliding block is arranged in the longitudinal groove, and the screw rod is in threaded connection with the longitudinal sliding block.

As a further limitation of the technical scheme, the longitudinal sliding block is connected with the top block.

The die design method of the novel crankshaft forging equipment is characterized by comprising the following steps of:

s1: optimizing a die drawing angle of a butterfly surface of a die;

the die drawing angle of the die on the butterfly-shaped surface of the crank is adjusted from 3 degrees to 6 degrees, so that the metal flow in the forging forming process is improved;

s2: optimizing the cavity structure of the connecting rod neck of the die;

the step-type cavity structure of the connecting rod neck of the pre-forging die is canceled, the flat cavity structure is changed, the cavity is deepened, the storage volume of the pre-forging die is increased, the rapid flow of materials at the crank position to the connecting rod neck cavity during final forging is reduced, and the folding is avoided;

s3: optimizing the design of a connecting rod gear weight reducing groove;

the position of a parting surface at the side of the crank connecting rod is adjusted, so that symmetrical parting of the upper die and the lower die is ensured as much as possible, and meanwhile, the height of a discharging area of a lower die of a neck of the pre-forging connecting rod is reduced, so that the discharging area of the pre-forging die is relatively gentle, large-angle deformation of metal in the forging process is reduced, and the flow speed of the metal is reduced;

s4: optimizing the die cavity structure of the large and small head end surfaces of the die;

the original end face protruding structure of the big end of the pre-forging die is changed into a large arc structure, so that the big end of the pre-forging die can still store a large amount of materials under the condition that the length of a roll blank is short during pre-forging, and the big end of a forging blank after final forging is free of folding defects.

Compared with the prior art, the invention has the advantages and positive effects that:

1. according to the invention, through optimization of the die design, the forging and folding defects of the crankshaft blank are completely eliminated, the reliability of the crankshaft is greatly improved, and the design provides a very effective reference function for the subsequent forging die design.

2. According to the invention, the die drawing angle of the die on the butterfly-shaped surface of the crank is adjusted from 3 degrees to 6 degrees, so that the metal flow in the forging forming process is improved; the connecting rod neck cavity of the pre-forging die is designed to be of a flat cavity structure, the depth of the cavity is deepened, the storage volume of the pre-forging die is increased, the rapid flow of materials at the crank position to the connecting rod neck cavity during final forging is reduced, and folding is avoided; the position of a parting surface of a crank connecting rod gear weight reducing groove is adjusted, so that an upper die and a lower die are symmetrically parting, the height of a discharging area of a lower die of a pre-forging connecting rod neck is reduced, the pre-forging discharging area is relatively gentle, large-angle deformation of metal in the forging process is reduced, and the metal flow speed is reduced; the large and small end surfaces of the pre-forging die are designed to be large arc structures, so that the large and small end parts can still store a large amount of materials under the condition that the length of a roller blank is short during pre-forging, and therefore the large and small end parts of a crankshaft blank after final forging are free of folding defects.

Drawings

Fig. 1 is a schematic view of a partial perspective structure of the present invention.

Fig. 2 is a schematic perspective view of the present invention.

Fig. 3 is a schematic perspective view of a mold according to the present invention.

FIG. 4 is a comparison of the optimal design of the butterfly face of the crank of the present invention.

FIG. 5 is a diagram of an optimized comparison of connecting rod neck cavity designs of the present invention.

FIG. 6 is a diagram showing an optimized comparison of the design of the connecting rod gear weight-reducing groove of the present invention.

FIG. 7 is a graph of the optimization and comparison of the design of the big and small head end surfaces of the present invention.

Fig. 8 is a diagram showing the effect of the design product before and after improvement.

In the figure:

1. a bottom plate, 11, L grooves, 12, transverse grooves, 13 and longitudinal grooves;

2. the film pressing assembly 21, the top plate 22, the hydraulic rod 23, the supporting guide rod 24 and the pressing block;

3. the die comprises a die 31, a butterfly-shaped surface die drawing angle 32, a connecting rod neck cavity structure 33, a connecting rod gear weight reducing groove 34 and a big and small head end surface cavity structure;

4. a top block;

5. the top block power assembly 51, the motor 52, the screw rod 521 and the longitudinal sliding block;

6. the device comprises a positioning assembly 61, a screw motor 62, a positioning U-shaped clamping groove 63, a transverse sliding block 64 and a transverse round rod.

Detailed Description

One embodiment of the present invention will be described in detail below with reference to the attached drawings, but it should be understood that the scope of the present invention is not limited by the embodiment.

The invention comprises a die 3, a positioning component 6 and a bottom plate 1, wherein the bottom plate 1 is provided with two groups of symmetrical transverse grooves 12; the positioning assembly 6 comprises symmetrical lead screw motors 61, sliding blocks on the symmetrical lead screw motors 61 are respectively and fixedly connected with positioning U-shaped clamping grooves 62, the symmetrical positioning U-shaped clamping grooves 62 are matched with the die 3, each transverse groove 12 is respectively provided with a transverse round rod 64, each transverse round rod 64 is respectively and fixedly connected with the bottom plate 1, each transverse groove 12 is respectively provided with a transverse sliding block 63, each transverse round rod 64 respectively passes through the corresponding transverse sliding block 63, and each transverse sliding block 63 is respectively and fixedly connected with the corresponding positioning U-shaped clamping groove 62; the die cavity of the die 3 comprises a butterfly surface die drawing angle 31, a connecting rod neck die cavity structure 32, a connecting rod baffle weight reducing groove 33 and a big and small head end surface die cavity structure 34, wherein the butterfly surface die drawing angle 31, the connecting rod neck die cavity structure 32, the connecting rod baffle weight reducing groove 33 and the big and small head end surface die cavity structure 34 are sequentially communicated.

The bottom plate 1 is fixedly connected with the film pressing assembly 2, the film pressing assembly 2 comprises a support guide rod 23, a group of support guide rods 23 are respectively connected with the top plate 21, the top plate 21 is fixedly connected with a group of hydraulic rods 22, and piston rods of the hydraulic rods 22 are respectively connected with a pressing block 24.

A set of said guide rods 23 pass through said press block 24.

The bottom plate 5 is connected with the top block power assembly 5, the top block power assembly 5 comprises a motor 51, the bottom plate 1 is fixedly connected with the motor 51, the bottom plate 1 is provided with a longitudinal groove 13, an output shaft of the motor 51 penetrates through a screw 52 connected with the bottom plate 1, a longitudinal sliding block 52 is arranged in the longitudinal groove 13, and the screw 52 is in threaded connection with the longitudinal sliding block 521.

The vertical sliding block 521 is connected with the top block 4.

The bottom plate 1 is provided with symmetrical L-shaped grooves 11, and the top blocks 4 are nested in the symmetrical L-shaped grooves 11.

The die design method of the novel crankshaft forging equipment is characterized by comprising the following steps of:

s1: optimizing a die drawing angle of a butterfly surface of a die;

the die drawing angle of the die on the butterfly-shaped surface of the crank is adjusted from 3 degrees to 6 degrees, so that the metal flow in the forging forming process is improved; the metal flow in the forging forming process is improved, redundant materials flow to the flash, and the defect of folding of the butterfly-shaped surface is avoided.

In order to improve the metal flow in the forging forming process, redundant materials flow to the flash, the die drawing angle of the die on the butterfly face of the crank needs to be increased, but the crank arm at the outermost end of the butterfly face is changed by increasing the die drawing angle on the butterfly face, and the risk of crank arm rate cracking during surface quenching is increased. In order to prevent the crank arm at the butterfly-shaped surface from being cracked during quenching of the machined connecting rod journal, the width of the crank arm at the outermost end of the butterfly-shaped surface needs to be larger than 11mm after machining of the connecting rod gear is required to be ensured during blank design, and when the die drawing angle is adjusted to 6 degrees, the thickness of the thinnest crank arm at the butterfly-shaped surface is 11.3mm.

And the initial unbalance amount of the crankshaft can be influenced by the adjustment of the die drawing angle on the butterfly surface, and the die drawing angle is adjusted to 6 degrees in design, so that the initial unbalance amount of the crankshaft is reasonably distributed and the integral dynamic balance of the crankshaft is easily realized.

S2: optimizing the cavity structure of the connecting rod neck of the die;

the step-type cavity structure of the connecting rod neck of the pre-forging die is canceled, the flat cavity structure is changed, the cavity is deepened, the storage volume of the pre-forging die is increased, the rapid flow of materials at the crank position to the connecting rod neck cavity during final forging is reduced, and the folding is avoided;

s3: optimizing the design of a connecting rod gear weight reducing groove;

the position of a parting surface at the side of the crank connecting rod is adjusted, so that symmetrical parting of the upper die and the lower die is ensured as much as possible, fluctuation of the parting surface is reduced, transitional flow of bars in an upper die cavity in the forging process is reduced, metal flow in the forging forming process is improved, meanwhile, the height of a discharging area of a lower die of a pre-forging connecting rod neck is reduced, the discharging area of the pre-forging die is relatively gentle, large-angle deformation of metal in the forging process is reduced, and the metal flow speed is reduced;

s4: optimizing the die cavity structure of the large and small head end surfaces of the die;

the original end face protruding structure of the big end of the pre-forging die is changed into a large arc structure, so that the big end of the pre-forging die can still store a large amount of materials under the condition that the length of a roll blank is short during pre-forging, and the big end of a forging blank after final forging is free of folding defects.

The working flow of the invention is as follows: the upper and lower molds of the mold 3 are placed. The forge piece is placed in the die cavity of the die 3, the screw motor 61 is controlled to rotate, the screw motor 61 drives the positioning U-shaped clamping groove 62 to move, the positioning U-shaped clamping groove 62 drives the transverse sliding block 63 to move along the transverse round rod 64 in the transverse groove 12, and the positioning U-shaped clamping groove 62 clamps the die 3. The motor 51 is controlled to rotate, the motor 51 drives the screw rod 52 to rotate, the screw rod 52 drives the longitudinal slide block 521 to move, and the longitudinal slide block 521 drives the top block 4 to move, so that the top block 4 is tightly attached to the U-shaped clamping groove 62. The hydraulic rod 22 is controlled to extend, so that the hydraulic rod 22 drives the pressing block 24 to move downwards along the supporting guide rod 23, and the pressing block 24 presses the die 3, thereby realizing forging.

And (3) effect verification:

after the die is optimally designed, 18000 crankshaft forging blanks are produced, folding defects of the blank butterfly-shaped surface, the crank arm, the connecting rod gear weight reducing groove, the big end face, the small end face and other parts are completely eliminated, the improvement effect is obvious, and the reliability of the crankshaft is greatly improved.

The above disclosure is merely illustrative of specific embodiments of the present invention, but the present invention is not limited thereto, and any variations that can be considered by those skilled in the art should fall within the scope of the present invention.

Claims (6)

1. Novel bent axle forging equipment, including mould (3), locating component (6) and bottom plate (1), its characterized in that:

the bottom plate (1) is provided with two groups of symmetrical transverse grooves (12);

the positioning assembly (6) comprises symmetrical screw motors (61), sliding blocks on the symmetrical screw motors (61) are respectively and fixedly connected with positioning U-shaped clamping grooves (62), the symmetrical positioning U-shaped clamping grooves (62) are matched with the die (3), transverse round rods (64) are respectively arranged in each transverse groove (12), each transverse round rod (64) is respectively and fixedly connected with the bottom plate (1), transverse sliding blocks (63) are respectively arranged in each transverse groove (12), each transverse round rod (64) respectively penetrates through the corresponding transverse sliding block (63), and each transverse sliding block (63) is respectively and fixedly connected with the corresponding positioning U-shaped clamping groove (62);

the die cavity of the die (3) comprises a butterfly-shaped surface die drawing angle (31), a connecting rod neck cavity structure (32), a connecting rod gear weight reducing groove (33) and a big and small head end surface cavity structure (34), wherein the butterfly-shaped surface die drawing angle (31), the connecting rod neck cavity structure (32), the connecting rod gear weight reducing groove (33) and the big and small head end surface cavity structure (34) are sequentially communicated.

2. The novel crankshaft forging apparatus according to claim 1, wherein: the base plate (1) is fixedly connected with the film pressing assembly (2), the film pressing assembly (2) comprises a group of supporting guide rods (23), the supporting guide rods (23) are respectively connected with the top plate (21), the top plate (21) is fixedly connected with a group of hydraulic rods (22), and piston rods of the hydraulic rods (22) are respectively connected with the pressing blocks (24).

3. The novel crankshaft forging apparatus according to claim 2, wherein: a set of guide rods (23) passes through the press block (24).

4. The novel crankshaft forging apparatus according to claim 1, wherein: the utility model discloses a motor, including bottom plate (5), top piece power pack (5) include motor (51), bottom plate (1) fixed connection motor (51), bottom plate (1) are provided with longitudinal groove (13), the output shaft of motor (51) passes bottom plate (1) connecting screw rod (52), be provided with in longitudinal groove (13) and indulge slider (52), screw rod (52) threaded connection indulge slider (521).

5. The novel crankshaft forging apparatus according to claim 4, wherein: the vertical sliding block (521) is connected with the top block (4).

6. The die design method of the novel crankshaft forging apparatus as recited in claim 5, comprising the steps of:

s1: optimizing a die drawing angle of a butterfly surface of a die;

the die drawing angle of the die on the butterfly-shaped surface of the crank is adjusted from 3 degrees to 6 degrees, so that the metal flow in the forging forming process is improved;

s2: optimizing the cavity structure of the connecting rod neck of the die;

the step-type cavity structure of the connecting rod neck of the pre-forging die is canceled, the flat cavity structure is changed, the cavity is deepened, the storage volume of the pre-forging die is increased, the rapid flow of materials at the crank position to the connecting rod neck cavity during final forging is reduced, and the folding is avoided;

s3: optimizing the design of a connecting rod gear weight reducing groove;

the position of a parting surface at the side of the crank connecting rod is adjusted, so that symmetrical parting of the upper die and the lower die is ensured as much as possible, and meanwhile, the height of a discharging area of a lower die of a neck of the pre-forging connecting rod is reduced, so that the discharging area of the pre-forging die is relatively gentle, large-angle deformation of metal in the forging process is reduced, and the flow speed of the metal is reduced;

s4: optimizing the die cavity structure of the large and small head end surfaces of the die;

the original end face protruding structure of the big end of the pre-forging die is changed into a large arc structure, so that the big end of the pre-forging die can still store a large amount of materials under the condition that the length of a roll blank is short during pre-forging, and the big end of a forging blank after final forging is free of folding defects.