The working state and overall structure of the aluminum profile extrusion press machine plant line
The control method of aluminum profile extrusion press machine plant line power is to use a 6-pole or 4-pole constant speed AC asynchronous motor to drive variable displacement piston pumps and vane pumps. The variable displacement plunger pump changes the variable mechanism of the oil pump to achieve speed regulation function according to the needs of extrusion speed, and the vane pump provides auxiliary action that requires hydraulic drive. It has the following drawbacks:
① The host will generate reactive power in standby mode.
② The actual working time of vane pump when providing auxiliary action in each Pressure-fed engine is only about ten seconds, and the rest of the time is to cut oil back through overflow, which will consume a certain amount of electric energy.
③ The service life of the oil pump will be shortened if it is in working or idle state for a long time.
④ The hydraulic oil will generate heat when the host is in standby mode and the motor and oil pump are idling.
After the extruder adopts a servo control system, the motor and oil pump will adjust the operating status and required motor speed in real-time under the control of PLC based on the working status and extrusion speed requirements of the extruder, truly reflecting the power required by the host. This reduces energy consumption, improves the service life of the oil pump, reduces the temperature of the hydraulic oil, improves the power factor of the power system, and improves the control accuracy of the extrusion speed. Adopting an extruder servo system, it can truly reflect the power and power consumption of the extruder, achieving intelligent control. Compared with the old hydraulic control system, the production of aluminum saves 15% to 20% electricity per ton.
The screw sleeve wrapped around the screw can be made into an integral structure, but it is usually equipped with a jacket to be used for circulating heating of steam or superheated oil, or for circulating water cooling. The purpose is to enable the extrusion function to accurately adjust the temperature of each working section. Most screw sleeves are equipped with pressure sensors and temperature sensors, as well as temperature control devices.
The inner surface of the screw sleeve is usually made into a groove shape, some are linear grooves, and some are spiral grooves. A spiral groove creates a positive downstream flow, while a straight groove hinders downstream flow. Therefore, straight grooves can lead to lower flow rates, but their mechanical shear effect is greater. The gap distance between the screw and its sleeve is usually kept to a small extent to reduce leakage flow.
At the end of the screw insert, molded discs with various shapes of eyelets are usually equipped, commonly referred to as die heads. The die head has Dwifungsi: extruding the extrudate into the required shape; It is used as a choke to increase the pressure in the maturing section of the extruder. Determining the geometric shape of the die head hole plays a crucial role in the shape and quality of the extruded product. We have developed and applied various forms of single pass molding dies, such as cylindrical hole molds, slot hole molds, annular hole molds, and double pass molding dies. The feed inside the double pass molding head comes from the discharge ports of two extrusion machines for single pass molding, and can be processed into extruded products with dual colors or flavors.