Operating Steps and Key Points of Aluminum Extrusion Machines

The use of an aluminum extrusion press includes a series of steps such as installation, adjustment, trial operation, operation, maintenance, and repair. Although it may seem complicated, in reality, it only requires following the instructions. However, operators must be familiar with the structural characteristics of the aluminum extrusion press they are operating in order to correctly grasp the extrusion process conditions and operate the machine properly. There are many types of extrusion presses; although the key points for operating them vary, they also have similarities.

一. Preparations Before Driving

1. Plastics for extrusion molding. The raw materials should meet the required drying standards and, if necessary, be further dried. Sift the raw materials to remove clumps, lumps, and mechanical impurities.

2. Check whether the water, electricity, and gas systems in the equipment are normal, ensure that the water and gas lines are unobstructed and leak-free, and verify that the electrical system, heating system, temperature controls, and various instruments are working reliably; perform a low-speed trial run of the auxiliary machines without load and observe whether the equipment operates normally; start the vacuum pump of the shaping table and check if it works properly; lubricate all sliding parts of the equipment. Any faults found should be addressed promptly.

3. Install the machine head and shaping sleeve. Select the appropriate machine head specification according to the type and size of the product. Install the machine head in the following order.

二. Drive

1. After the constant temperature, the machine head and the extruder flange bolt should be tightened again before driving to eliminate the difference between the bolt and the machine head. When tightening the flange nut of the machine head, it is required to be tight around the edge, otherwise the material will be run.

2. To start, select the ready start button, then connect the start button, and then slowly rotate the screw speed adjustment knob, and the screw speed starts slowly. Then gradually speed up, while adding a small amount of material. When feeding, pay close attention to the changes in the main engine ammeter and various indicator heads. And add enough material as needed, and the twin screw extruder uses a metering feeder to feed evenly and at the same speed.

3. When the mouth mold is uniformly discharged and the plastic is good, the tractor shaping sleeve can be carried out. The judgment of the degree of plasticization needs to be based on experience, generally according to the appearance of the extruded material, that is, the surface is glossy, no impurities, no foaming, coke and discoloration, and the extrusion material is squeezed finely by hand to a certain extent without burrs and cracks, and has a certain elasticity, which means that the material is well plasticized. If the plasticization is poor, the screw speed, barrel and head temperature can be adjusted appropriately until the requirements are met.

4. In the extrusion production process, check whether the various process parameters are normal according to the process requirements, and fill in the process record sheet. Check the quality of profile products according to quality inspection standards, and take timely measures to solve problems found.

三. Stopping the Machine

1. Stop feeding material, extrude all the plastic from the extruder, and when the screw is exposed, turn off the power to the barrel and the head, and stop heating.

2. Turn off the power to the aluminum profile extruder and auxiliary machines, so that the screw and auxiliary machines stop operating.

3. Open the head connection flange and dismantle the head. Clean the die plate and all components of the head. To prevent damaging the inner surface of the head during cleaning, residual material inside the head should be removed with steel scrapers or steel sheets. Then use sandpaper to remove any plastic adhered inside the head, polish it, and apply machine oil or silicone oil to prevent rust.

4. Cleaning the screw and barrel: after removing the head, restart the main machine, add purging material, and clean the screw and barrel. At this time, use a low screw speed to reduce wear. Once the purging material is ground into powder and fully extruded, use compressed air through the feed port and exhaust port repeatedly to blow out any remaining pellets and powder. After confirming there is no material left inside the barrel, reduce the screw speed to zero, stop the extruder, and turn off the main power and the main cooling water valve.

5. Safety precautions during aluminum profile extrusion include electrical, thermal, mechanical rotation, and the handling of heavy components. The extrusion workshop must be equipped with lifting equipment for installing and dismantling the head, screw, and other heavy components to ensure safe production.