Accuracy and stiffness of dies
(1) Mould accuracy
The accuracy of die includes dimension accuracy, shape accuracy, position accuracy and surface roughness. The precision of die is mainly embodied in the precision of die parts and matching accuracy.
The precision of die working parts is higher than that of product parts. For example, the accuracy of cutting edge size is higher than that of product parts. Usually the accuracy of measurement is not the accuracy of working state (such as blanking clearance), that is, static accuracy. However, under the influence of working conditions, static and dynamic accuracy are transformed into dynamic accuracy, which is a real data with practical significance.
Generally, the precision of die should match the precision of product. With the development of manufacturing technology and the progress of die processing technology, the precision of die will be improved correspondingly, and the interchangeability production of die parts will become a reality.
(2) Mould stiffness
It is of great significance to high-speed stamping die, large parts stamping forming die, precision plastic die and large plastic die. When a large elastic deformation occurs, not only the dynamic accuracy of the die is affected, but also the relevant die can work normally. Therefore, in the design of the die, while meeting the strength requirements, the rigidity of the die should be guaranteed and the production should be carried out at the same time to avoid additional deformation due to improper handling.
Mold production cycle
Mould production cycle refers to the qualified mould from accepting the purchase order of the mould to testing after delivery. At present, the production cycle of the die-casting die is short, so the length of the production cycle of the mould measures the logo of the mould enterprise, the relationship between the production capacity and the technical level of the mould enterprise stands firm in the fierce market competition. At the same time, the length of the mould production cycle is also an index to measure a country's mould technology management level.
The main factors affecting the production cycle of die and mould are: (1) standardization of die and mould technology and production; (2) professional level of die and mould enterprises; (3) advanced die and mould production technology; (4) level of die and mould production management.
Mold production cost
Mold production cost refers to the total cost paid by the enterprise for the production and sale of the mould. The production cost of mould includes raw material cost, external parts cost, external parts cost, equipment depreciation, operation cost and so on. It is essentially divided into production costs, non-production costs and external production costs. Generally speaking, the production cost of mould refers to the production cost directly related to the production process of mould.
The main factors affecting the cost of die production are: (1) the complexity of die structure and the height of die function; (2) die accuracy; (3) die material selection; (4) die processing equipment; (5) the degree of standardization of die and enterprise production specialization.
Die life refers to the total number of parts, which can be processed under the premise of ensuring the quality of parts, including the sum of the number of parts processed before and after repeated grinding surface and vulnerable parts replacement work. Generally, in the stage of die design, the type of die suitable for mass production or the total number of parts produced by the die should be defined, that is, the design life of the die. The normal damage forms of different types of dies are different, but generally speaking, the damage forms of working face are friction damage, plastic deformation, cracking, fatigue damage, bite and so on.
The main factors affecting die life are as follows:
(1) Die structure-reasonable die structure is conducive to improving the bearing capacity of the die and reducing the mechanical load it bears; (2) Die material-selection according to the size of the parts produced; (3) Die processing quality-Defects of die parts in mechanical processing, EDM, quenching and surface treatment, etc., will affect the wear resistance, bite resistance and fracture resistance of the die. Force has a significant impact; (4) The working state of the die - the working state of the die, the accuracy and stiffness of the equipment used, lubrication conditions, the pre-treatment state of the processing materials, the preheating and cooling conditions of the die have an impact on the life of the die; the four technical and economic indicators affect and restrict each other. In the actual production process, these factors should be comprehensively balanced according to the product parts and objectives.