CN111922269A

CN111922269A - Crank forging and extruding process

Info

Publication number: CN111922269A
Application number: CN202010901776.6A
Authority: CN
Inventors: 赵怀志
Original assignee: Chongqing Junding Machinery Manufacturing Co ltd
Current assignee: Chongqing Junding Machinery Manufacturing Co ltd
Priority date: 2020-09-01
Filing date: 2020-09-01
Publication date: 2020-11-13

Abstract

The invention relates to a crank forging extrusion process, which comprises a blank placing procedure and a forming procedure; the blank placing procedure comprises the steps of manually clamping a bar heated to the process temperature by using a clamp, forming a rough blank with a certain length, steps and taper by using an air hammer and a pull rod die, and pressing the rough blank into a cake-shaped piece with a certain diameter and a certain thickness by using a single-point press; the forming process comprises the steps of carrying out extrusion forming on the cake-shaped piece and carrying out finishing and trimming. After the stem pulling process or after the stem pulling process, the single-point press is used for extrusion, so that the influence of human factors is less, and the defects of the previous working procedure can be found in time. The extrusion process adopts a closed die sleeve open mode, can effectively prevent die dislocation, has no draft angle at the rod part of the lower die for molding, and is easy for rod part molding. Finishing and trimming are carried out, the fine shaping die and the trimming die are made into a whole, 2 processes are completed by one-time clamping action, the processes are combined, equipment is reduced, and personnel are reduced.

Description

Crank forging and extruding process

Technical Field

The invention relates to the technical field of crank production and processing, in particular to a crank forging and extruding process.

Background

The crank is produced and processed by the following process:

firstly, a conventional forging process:

firstly, heating a bar stock to a process temperature, then forming a step shaft with taper through a rod pulling process, then forming at one time by using a die, finishing and trimming a product formed by the die, and finally performing heat treatment.

Secondly, a conventional extrusion process:

firstly, heating a bar stock to a process temperature, then upsetting the blank into a cylindrical shape, then molding the blank once by using a mold, finishing and trimming the product molded by the mold, and finally performing heat treatment.

According to the conventional production process, the produced crank is easy to have defects such as cracks, and the crank is easy to break in the subsequent use process, so that the safety performance is influenced. The die for forming is shown in the attached drawing figure 1 of the specification, an open die mode is adopted for processing, the forming upper die and the forming lower die are staggered and tilted, the subsequent machining is influenced, and the number of reworking scrapped parts is large. And when follow-up finishing and side cut, need adopt punch press and side cut mould alone to cut edge, the wholeness is poor, still needs twice clamping, and is inefficient, and equipment is many, and required personnel are many.

Disclosure of Invention

Aiming at the defects of the prior art, the technical problem to be solved by the application of the patent is how to provide a crank forging and extruding process which can improve the integrity of a crank, prolong the service life and reduce cracks.

In order to solve the technical problems, the invention adopts the following technical scheme:

a crank forging extrusion process comprises a blank placing procedure and a forming procedure; the blank placing procedure comprises the steps of manually clamping a bar heated to the process temperature by using a clamp, forming a rough blank with a certain length, steps and taper by using an air hammer and a pull rod die, and pressing the rough blank into a cake-shaped piece with a certain diameter and a certain thickness by using a single-point press; the forming process comprises the steps of carrying out extrusion forming on the cake-shaped piece and carrying out finishing and trimming.

The extrusion forming comprises an extrusion die, and the extrusion die adopts a closed die sleeve opening mode. The extrusion die comprises an upper die and a lower die, wherein the upper die is provided with an upper forming surface which is protruded downwards, the lower forming surface which is sunken downwards and matched with the upper forming surface is arranged on the lower forming die, the upper die is provided with an upper die cavity, the lower die is provided with a lower die cavity, the upper die cavity and the lower die cavity are arranged right oppositely, and a parting surface and a fly are formed between the upper forming surface and the lower forming surface.

Wherein the finishing trim comprises a finishing trim die. The finishing and trimming die comprises an upper finishing and trimming die and a lower finishing and trimming die, the upper finishing and trimming die is provided with an upper finishing cavity, the lower finishing and trimming die is provided with a lower finishing cavity, the upper finishing cavity and the lower finishing cavity are arranged oppositely, the upper finishing cavity is provided with an upper finishing surface, the upper finishing and trimming die is provided with a trimming surface, and the lower finishing and trimming die is upwards protruded to the trimming surface to form a boss.

The invention has the beneficial effects that:

1. the conventional stem pulling process has more manual operations, more human influence factors and higher requirements on the skill level of an operator. After the stem pulling process or after the stem pulling process, the single-point press is used for extrusion, so that the influence of human factors is less, and the defects of the previous working procedure can be found in time.

2. The extrusion process adopts a closed die sleeve open mode, can effectively prevent die dislocation, has no draft angle at the rod part of the lower die for molding, and is easy for rod part molding.

3. Finishing and trimming are carried out, the fine shaping die and the trimming die are made into a whole, 2 processes are completed by one-time clamping action, the processes are combined, equipment is reduced, and personnel are reduced.

Drawings

Fig. 1 is a schematic structural view of a mold formed in the background art.

Fig. 2 is a schematic structural view of a rough blank.

Fig. 3 is a schematic structural view of an extrusion die.

Fig. 4 is a schematic structural view of a finishing trimming die.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings. In the description of the present invention, it is to be understood that the orientation or positional relationship indicated by the orientation words such as "upper, lower" and "top, bottom" etc. are usually based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplicity of description, and in the case of not making a reverse description, these orientation words do not indicate and imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore, should not be interpreted as limiting the scope of the present invention; the terms "inner and outer" refer to the inner and outer relative to the profile of the respective component itself.

As shown in fig. 2-4, a crank forging and extruding process comprises a blank placing process and a forming process; the blank placing procedure comprises the steps of manually clamping a bar heated to the process temperature by using a clamp, forming a rough blank 1 with a certain length, steps and taper by using an air hammer and a pull rod die, and pressing the rough blank into a cake-shaped piece with a certain diameter and a certain thickness by using a single-point press; the forming process comprises the steps of carrying out extrusion forming on the cake-shaped piece and carrying out finishing and trimming.

The extrusion forming comprises an extrusion die, and the extrusion die adopts a closed die sleeve opening mode. The extrusion die includes mould 2 and shaping lower mould 3 in the shaping, the mould has the last shaping surface that downward protrusion set up in the shaping, the shaping lower mould has undercut and the lower shaping surface that matches with last shaping surface, the mould has last mould cavity in the shaping, the shaping lower mould has lower mould cavity 5, it is just to setting up to go up mould cavity and lower mould cavity, it forms the parting plane and flies 4 to go up between shaping surface and the lower shaping surface.

Wherein the finishing trim comprises a finishing trim die. The finishing and trimming die comprises an upper finishing and trimming die 6 and a lower finishing and trimming die 7, the upper finishing and trimming die is provided with an upper finishing cavity 8, the lower finishing and trimming die is provided with a lower finishing cavity, the upper finishing cavity and the lower finishing cavity are arranged oppositely, the upper finishing cavity is provided with an upper finishing surface 9, the upper finishing and trimming die is provided with a trimming surface 10, and the lower finishing and trimming die protrudes upwards to the trimming surface to form a boss 11.

The invention has the beneficial effects that:

3. Finishing and trimming are carried out on the fine shaping die and the trimming die into a whole, 2 processes are completed by one-time clamping action, the processes are combined, trimming is carried out on a product by using the trimming surface, and simultaneously shaping is carried out by using an upper shaping cavity and a lower shaping cavity, so that equipment and personnel are reduced.

Finally, it should be noted that: various modifications and alterations of this invention may be made by those skilled in the art without departing from the spirit and scope of this invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

Claims

1. A crank forging extrusion process is characterized by comprising a blank placing procedure and a forming procedure;

the blank placing procedure comprises the steps of manually clamping a bar heated to the process temperature by using a clamp, forming a rough blank with a certain length, steps and taper by using an air hammer and a pull rod die, and pressing the rough blank into a cake-shaped piece with a certain diameter and a certain thickness by using a single-point press;

the forming process comprises the steps of carrying out extrusion forming on the cake-shaped piece and carrying out finishing and trimming.

2. The crank forging extrusion process according to claim 1, wherein the extrusion molding comprises an extrusion die which adopts a closed die-in-die manner.

3. The crank forging extrusion process according to claim 2, wherein the extrusion die comprises an upper forming die and a lower forming die, the upper forming die is provided with an upper forming surface which is arranged in a downward protruding manner, the lower forming die is provided with a lower forming surface which is arranged in a downward recessed manner and matched with the upper forming surface, the upper forming die is provided with an upper die cavity, the lower forming die is provided with a lower die cavity, the upper die cavity and the lower die cavity are arranged in a right-to-right manner, and a die parting surface and a flying surface are formed between the upper forming surface and the lower forming surface.

4. The crank forging extrusion process of claim 3 wherein the finishing trim includes a finishing trim die.

5. The crank forging extrusion process according to claim 4, wherein the finishing trimming die comprises an upper finishing trimming die and a lower finishing trimming die, the upper finishing trimming die is provided with an upper finishing cavity, the lower finishing trimming die is provided with a lower finishing cavity, the upper finishing cavity and the lower finishing cavity are oppositely arranged, the upper finishing cavity is provided with an upper finishing surface, the upper finishing trimming die is provided with a trimming surface, and the lower finishing trimming die is upwards protruded to form a boss opposite to the trimming surface.