What is the structure of an extruder? Rubber extruder manufacturer answers your questions

Rubber extruder manufacturer: Generally speaking, the most common and basic type of extruder is the single screw extruder. Its structure mainly includes six parts: transmission, feeding device, barrel, screw, machine head, and mold. What is the transmission part of the extruder? Rubber extruder manufacturer answers your questions!

The transmission part is usually composed of a motor, a reducer, and bearings. During the extrusion process, the screw speed must be stable and not vary with the screw load in order to maintain uniform product quality. However, in different situations, the screw should be variable speed to meet the requirements of a device that can extrude different plastics or products. Therefore, this part generally uses devices such as AC commutator motors and DC motors to achieve continuously variable transmission. The general screw speed is 10-100 revolutions per minute.

What is the structure of an extruder? Rubber extruder manufacturer answers your questions

Rubber extruder manufacturer: The function of the transmission system is to drive the screw, supply the torque and speed required by the screw during the extrusion process, usually consisting of a motor, reducer, and bearings. Under the premise of basically the same structure, the manufacturing cost of a reducer is roughly proportional to its overall size and weight. Due to the large shape and weight of the reducer, more materials are consumed during manufacturing, and the bearings used are also relatively large, which increases the manufacturing cost.

For extruders with the same screw diameter, high-speed extruders consume more energy than conventional extruders, requiring double the motor power and corresponding increase in the number of gearbox bases. But high screw speed means low reduction ratio. Compared with reducers of the same size, the gear module of low reduction ratio reducers increases, and the load-bearing capacity of reducers also increases. Therefore, the increase in volume and weight of the reducer is not linearly proportional to the increase in motor power. If the extrusion volume is taken as the denominator and divided by the weight of the reducer, there are fewer high-speed extruders and more ordinary extruders. From the perspective of unit output, the motor power and reducer weight of high-speed extruders are small, which means that the manufacturing cost of high-speed extruders per unit output is lower than that of ordinary extruders.

What is the feeding device of the extruder? Rubber extruder manufacturer answers your questions!

Generally, granular materials are used for feeding, but strip or powder materials can also be used. Loading equipment typically uses a conical hopper, whose capacity needs to provide at least one hour of supply. The bottom of the hopper is equipped with a cutting device for adjusting and cutting off the flow of materials, and the side of the hopper is equipped with observation holes and calibration measuring devices. Some hoppers may also be equipped with pressure reducing or heating devices to prevent the raw materials from absorbing moisture from the air, or some buckets may have their own mixers that can automatically add or charge materials.

What is the material bucket of the extruder? Rubber extruder manufacturer answers your questions!

Generally, it is a metal bucket made of composite steel pipes lined with alloy steel or alloy steel. Its basic characteristics are high temperature resistance, pressure resistance, sturdiness, wear resistance, and corrosion resistance. Generally, the length of the barrel is 15-30 times its diameter, and its length is based on the principle of material being fully heated and plasticized uniformly. It should have sufficient thickness and rigidity, and the interior should be smooth, but some are engraved with various grooves to increase friction with the plastic. The outer part of the barrel is equipped with an electric heater, temperature automatic control device, and a cooling system using heating methods such as resistors and inductors.