Cadcamcae integrated technology for the hottest pr

2022-07-26
  • Detail

With the continuous development of manufacturing technology, energy-saving, precise and efficient forming technology has become one of the key research and development directions in the field of metal plastic processing. Precision forging technology is more and more widely used in automobile industry. Some typical forgings in the automotive industry, including polar claw, bevel gear, coupling, journal, inner star wheel, cross shaft, outer star wheel, three pin sleeve, etc., are stress-bearing parts with high mechanical performance requirements. If the traditional hot die forging process is used for production, the consumption of raw materials and subsequent machining will be large, the production cost will be high, and the metal streamline will be cut off a lot, and the mechanical performance of the parts will be reduced; If the precision forging process (warm forging, cold forging or warm forging cold finishing) is adopted for production, high dimensional accuracy and surface quality can be obtained, and net formed or near net formed parts can be produced, which greatly reduces the consumption of raw materials and subsequent machining, and the die life is long, which can ensure the mechanical properties of parts. Automobile parts are generally in large quantities, and good economic benefits can be obtained by high-efficiency precision forging

die technology is the most important link in the precision forging process chain. The high dimensional accuracy and surface quality of precision forgings put forward higher requirements for die design and machining technology. The automation trend of precision forging production line increases the complexity of precision forging die. High efficiency die cad/cam/cae... CAX platform has become the key technology for precision forging enterprises to win in the fierce market competition

2. Characteristics of precision forging die

for typical precision forging parts, if hot forging blanks are used for subsequent cutting, the cutting volume is large, the efficiency is low, and the cost is high. However, after the net forming or near net forming technology is adopted, the inner surface of the part can meet the requirements of the final product directly or through a grinding process, which greatly improves the production efficiency

compared with ordinary hot forgings, the difficulty of developing precision forgings and their dies is mainly reflected in the following three aspects:

(1) the requirements for dimensional accuracy of forgings are high. For precision forgings, the key dimensional tolerance of the inner cavity is within ± 0.05mm, so the requirements for die accuracy are higher, which increases the difficulty of die design, die processing and precision forging process

(2) for clean formed or near net formed surfaces, the filling of small structures increases the difficulty of die design and precision forging process. It is necessary to use CAE software to simulate and analyze the small chamfers and fillets in the inner cavity of precision forgings, otherwise the number of die tests will be greatly increased

(3) for the net formed surface, the elastic deformation of the die and the subsequent heat treatment deformation of the fine forging may exceed the dimensional tolerance of the forging, and the compensation for these two types of deformation must be considered when designing the die

for precision forgings, the materials are all medium carbon steel, and the inner cavity surface is complex. It is difficult to form by using the simple cold forging process. Generally, the comprehensive process of "warm forging + cold finishing" is used. The warm forging adopts the fan cap cover made of composite materials, which can provide a multi station forming mode with lighter weight, simplified anti ice structure, better corrosion resistance and better fatigue resistance. When designing the pre forged blank of each step, the coordination and consistency of each deformation step to achieve the permanent rehabilitation of damaged tissues or organs should be fully considered to avoid various forming defects; The coordination of warm forging deformation and cold finishing deformation is the key for "warm forging + cold finishing" to continue to work with customers on the forming process according to the force value of the tested range of the experimental machine

as mentioned above, precision forging is mostly used in mass production in the automotive industry, with a high degree of automation and fast production pace. In the production process, efficient lubrication and cooling system and automatic unloading and feeding mechanism are required, and the whole set of molds becomes a relatively complex system; It breaks through the simple die structure of upper die, lower die and ejector rod in traditional hot forging. Complex die structure objectively requires a relatively perfect cad/cae system for die design and management

at the same time, the automatic and multi station die system needs high die life, otherwise the production efficiency of precision forging will be greatly reduced due to the time of frequent die replacement. Therefore, under the condition of certain die material properties, the reasonable deformation and flow of forging blank is an important technology to improve the die life. The organic combination of cad/cae technology can greatly improve the rationality of deformation flow distribution

as mentioned above, the high precision, high production efficiency and high die life of precision forgings and their dies put forward higher requirements for the design, processing and management of precision forging dies; High efficiency cad/cam/cae... CAX system is the key technology to solve these problems

3. Die cad/cam/cae integration technology

schematic diagram of cad/cam/cae integration technology process of precision forging die (omitted)

it can be seen from the flow chart that the entire cad/cam/cae process is centered on the 3D model of precision forgings and their pre forged blanks. Mold design, finite element simulation analysis, mold CNC processing, mold CMM (three coordinate) detection and precision forging CMM detection are all based on the transmission of 3D mold of these forgings, thus eliminating the inaccuracy of geometric information transmitted by two-dimensional drawings, Make the final precision forgings highly consistent with the designer's intention

it can also be seen from the flow chart that the implementation of die cad/cam/cae integration technology mainly requires hardware such as workstations, CNC hard working equipment, CMM measurement, and 3D CAD, cam, and CAE software. At present, most 3D CAD software can output IGS and other general model file formats for cam and CAE software to call, so as to realize the identity of CAD, cam and CAE 3D models. The three-dimensional model identity ensures the closed-loop characteristics of CAX chain, such as precision forging design, die design, die processing, die detection, precision forging detection, etc., which is difficult to produce design and processing errors, so as to improve the development efficiency of precision forgings

4. Advantages of die cad/cam/cae integration technology

precision forging die cad/cam/cae integration technology has the following advantages:

(1) all die design, processing and inspection are based on the 3D model of precision forgings and their pre forged blanks to realize the closure of die CAX chain

(2) 3D design based on 3D assembly can easily control the volume of precision forgings and pre forged blanks; 3D design and assembly can eliminate mold design errors in time

(3) 3D model greatly reduces the inaccuracy of 2D drawings in the process of technical information transmission. Especially under the condition of global mold procurement, the 3D model that can be directly used for cam processing eliminates the ambiguity of mold geometric information transmission. With the help of the Internet, the number of round-trip confirmation of mold drawings is greatly reduced and the delivery cycle is shortened

(4) 3D design models of forgings and dies can be directly introduced into CAE (finite element) simulation analysis system

(5) CAD parameterization technology facilitates the establishment of a precision forging and die development platform based on the precision forging production line (die machining)

(6) compared with the traditional EDM, the hard machining technology saves one ring of electrode manufacturing, shortens the mold processing cycle and improves the mold processing accuracy

The rapid development of computer hardware, software, die processing and testing technology makes the precision forging die cad/cam/cae integration technology a feasible technology for forging enterprises. Precision and high efficiency are the development trend of modern forging industry; The company's application of this technology shows that only based on the high-efficiency die cad/cam/cae... CAX platform can the high-efficiency development of precision forgings and their dies be realized

Copyright © 2011 JIN SHI