Die casting mold design

 

1, Features of die casting process: Internal structure of die casting is dense, mechanical properties are excellent, dimensional accuracy is high, surface quality is good. Application: Die casting process plays an important role in machinery industry, aerospace industry, automobile manufacturing industry and daily light industry.

 

2. (Typical die-casting filling) Ideal flow state: start with sequential filling at low speed from one end, vent gas, then increase filling speed, fill cavity, and compact die-casting. 1 requires that die-casting alloy does not have a high overheating temperature and has good fluidity. 2 Linear shrinkage rate and tendency to crack are small. 3 Crystallization temperature range is small. 4. Have a certain high temperature strength. 5 High strength at normal temperature 6 Mold production process 7 Master characteristics of die-casting alloy
4. Types of Die Casting Machine: currently in production, two common types of die casting machine are cold die casting machine and hot die casting machine. Among them, horizontal die casting machine has many applications, vertical cold-pressing chamber die casting machine has been rarely used.

 

5. Die casting process 1. Die casting process is a comprehensive application process that organically combines three major elements of die casting productions: die-casting alloy, die casting die and die casting machine. Correctly selecting and adjusting die casting process parameters is basis for ensuring quality of die casting parts, giving full play to productivity of die casting machine, correctly designing die casting die. In particular, reasonable selection of process parameters such as injection pressure, ejection speed, pouring temperature, die temperature and filling time are necessary conditions for production of qualified die castings.
6. Die casting process is to optimize technology of die casting structure design, which is one of three major elements of die casting productions. 1. Simplifies mold and prolongs service life of mold. 2. Reduces core-pulling mechanism. 3. Convenient demolding and core-pulling of die casting parts 4. Prevent deformation 5. Casting into insert 6. When changing from other methods to die-casting, pay attention to structural modification matter
7. Structure of die castings 1. Dimensional accuracy of die castings 2. Surface shape and position 3. Surface roughness

 

8. Die casting mold composition is mainly composed of fixed mold and moving mold. Fixed mold is connected with injection mechanism of die casting machine, fixed on fixed mold mounting plate, pouring system communicates with pressure chamber. Movable mold is installed on movable mold mounting plate of die casting machine, movable mold mounting plate moves with fixed mold to close or open mold. Role and type of parting surface design of die casting mold: principle of selecting parting surface is to keep die casting part in moving mold part as much as possible after mold is opened for demolding. Parting surface should have good overflow exhaust conditions for die casting mold cavity, so that cold metal and gas in cavity entering cavity first enter overflow system. Parting surface should be avoided to coincide with reference surface of casting. Positions that require high dimensional accuracy, shapes or inner holes that require high coaxiality should be located in same half mold as much as possible.
9. Die casting mold parting surface design. Parting surface should have good overflow and exhaust conditions for die casting mold cavity, so that cold metal and gas in cavity entering cavity first enter overflow system and are discharged. Parting surface should avoid coincidence with reference plane of casting. Parts with high dimensional accuracy requirements and shape or inner hole with high coaxiality requirements should be located in same half mold as much as possible. Channel for filling cavity by the metal liquid under pressure is composed of a straight runner, a horizontal runner, an inner runner and remaining material. Role: Metal liquid is sent to cavity from injection nozzle of hot die casting machine or from cold pressing chamber die casting machine.
10. Metal system of pouring system fills channel of cavity under pressure. It consists of a sprue, a runner, an inner runner and remaining material. Role: Metal liquid is sent to cavity from injection nozzle of hot die casting machine or from cold pressing chamber die casting machine. Important design of gating system is design of runner. Form of runner: side runner, center runner, top runner, ring runner, gap runner, spot runner. Main points of design of runner 1. Consideration of direction of metal flow from runner 2. Number of runners is mainly single. Large-scale castings, boxes, frame castings and special castings can use multiple runners. 3. Consider location of runner. 4. For thin-walled complex castings, use thinner runners. Thicker caster for general structural castings
12. Structural design of die casting mold application
Main points of design of sprue 3. Consider location of internal runner 4. Thin-walled complex casting takes a thinner internal runner. Thicker caster for general structural castings

13. Design points of overflow tank

Materials, technical requirements and design cases of die casting mold 1. Correctly arrange position of overflow tank in mold 2. Design points of overflow tank 3. Volume of overflow tank