According to the design theory of production system, the structure of compound squeeze casting forming system is composed of logistics system, energy flow system and information flow system.
1.Logistics system
The composite squeeze casting forming system completes a series of process activities, such as pre mold, melt transportation, mold filling, etc., fills the metal liquid at a predetermined temperature into the mold cavity composed of the mold at a specified speed, and obtains the castings with a predetermined shape through mold filling and extrusion operations. This process not only completes the transformation of metal melt into castings, but also realizes the transfer of materials from one process to another, Therefore, the process flow of squeeze casting system can be regarded as a production logistics system. The system smoothly transfers the molten metal to each station and transfers the finished products to the storage area, including the following three subsystems:
(1) Molten liquid conveying system. The system is composed of an air pressure holding furnace, an air pressure driving device and an infusion pipeline, which transmits molten liquid from the holding furnace to the mold filling device.
(2) Filling system. The system is composed of a mold filling head and a mold filling cavity. It is mainly responsible for sending the metal melt conveyed from the holding furnace to the mold cavity into the mold cavity. At the same time, while the upper mold squeezes the metal melt, the mold filling head can maintain the position in the mold filling cavity, or make minor changes according to the metal melt to ensure a certain volume of metal melt in the mold cavity.
(3) Pick up system. The system is composed of mechanical arm, conveyor belt and other related mechanical transmission devices, which transport the formed castings from the mold cavity to the conveyor belt or casting placement area.
2.Energy flow system
The energy flow system of composite squeeze casting provides the energy required for each processing procedure, including the following three subsystems:
(1) Heating and insulation system. The system is composed of melting furnace, mold temperature machine and heating jacket, which converts electric energy into heat energy. The melting furnace melts the metal blank and maintains a reasonable mold filling temperature; The mold temperature machine ensures that the mold is within a reasonable temperature range, that is, preheat the mold before pressing, and cool the mold during the working process; The heating sleeve ensures that the filling cavity has a temperature suitable for filling.
(2) Casting forming system. The system consists of a forming die and a hydraulic press, which converts electrical energy into mechanical energy. Its function is to ensure the dimensional parameters of castings, perform various actions in the process of composite squeeze casting, and transfer the forming force to the molten metal in the mold cavity.
(3) Hydraulic system. The system is composed of hydraulic cylinder, valve components and auxiliary devices, and converts electric energy into hydraulic energy. Its function is to provide power for the process of compound squeeze casting. The system determines the performance index of the equipment.
3.Information flow system
The information flow system of the composite squeeze casting system provides the information required by each component and timely feedback, which is composed of a measurement system and a control system. The coordinated operation of measuring system and control system makes the whole compound squeeze casting forming system work normally. The information system is closely connected with the logistics system and the energy flow system, and even exists in other systems as a subsystem. For example, the pneumatic infusion process in the melt conveying system requires temperature detection, accurate control and cooperation to ensure the stability of the temperature of the molten metal conveyed in the process.