What is the injection molding temperature of POM material? As a commonly used engineering plastic, POM has a wide range of uses. Various fastening parts, wear-resistant, high rigidity, and steel-like products can be manufactured using POM materials. However, for newcomers to injection molding or customers who have not used POM material injection molding before, it is very important to understand the injection temperature of POM material. Next, we will explain this knowledge in detail.
POM plastic injection molding is divided into drying treatment before injection molding, material temperature during injection molding, nozzle temperature and mold temperature during molding.
Due to the low water absorption rate of POM materials, it can usually be processed without drying, but it is not ruled out that some POM raw materials are placed in a relatively humid environment for a long time before processing. At this time, drying treatment needs to be kept at 80-120 degrees for 2 -4 hours to dry.
Since the melting point of POM is about 170 degrees, specifically, the copolymerization POM is 165 degrees, and the homopolymerization POM is 175 degrees, so in order to ensure that the temperature of the middle section of the barrel before POM forms a fluid state must be kept above 175 degrees, the specific parameters are the front end of the barrel The temperature needs to be 200 degrees, the middle part is 180 degrees, the rear part of the material needs to be kept between 150 and 180 degrees, and the nozzle temperature needs to be kept between 170 and 180 degrees. In order to ensure that the fluid POM material is injected into the mold smoothly, if the product itself belongs to The temperature of the yellow wall type nozzle should be increased to no more than 210 degrees, depending on the situation. This can improve the fluidity of the POM material to a certain extent and prolong the curing time of the POM material in the mold so that the POM material can fill the entire small area. mold.
When the fluid POM material is injected into the mold through the nozzle, in order to ensure the molding effect of the material and improve the impact resistance strength of the product, the mold itself needs to be kept between 80 and 100 degrees, in order to ensure that the POM machining material has enough cooling time Time so the mold temperature can not be too low.
The production and processing range of most POM is 170-230°C, and the general use temperature is 170-200°C. The mold temperature must be set according to the physical properties, appearance, dimensional changes in use and quality requirements of the molding cycle of the molded product.
POM plastic materials have distinct melting points, high melt viscosity and poor fluidity. Although POM is slightly less hygroscopic than PA, it still needs to be dried and cleaned before fabrication due to size and surface quality considerations. Fine gear parts such as gears: 100~120°C, 4~8 hours; general parts: 80~90°C, 3~4 hours. POM is usually used in sliding and rolling mechanical parts with strict requirements on lubrication, wear resistance, stiffness and dimensional stability, and its characteristics are particularly superior. Therefore, pom is mainly used in automotive, electrical and electronics, industrial machinery, irrigation supplies and plumbing fittings.
In general, the processing range of most POM is 170-230°C, and the general use temperature is 170-200°C. The mold temperature must be set according to the physical properties, appearance, dimensional changes in use and quality requirements of the molding cycle of the molded product. For example, in order to avoid scale change when the application environment temperature of the molded product is high, the temperature of the mold should be higher than the application temperature or tempered. If this is expressed as a specular requirement from the outside, the mold temperature must be set to about 230°C.
The mold temperature is controlled at 80-90°C.
Melt temperature:
- POM-H can be set to 215°C (190°C-230°C)
- POM-K can be set to 205°C (190°C-210°C)
- POM-H can stay at 215°C for 35 minutes, POM-K can stay at 205°C for 20 minutes without serious decomposition
Residence time:
If the equipment does not have a melt retention point
- POM-H can stay at 215°C for 35 minutes
- POM-K can stay at 205°C for 20 minutes without serious decomposition
The melt cannot stay in the barrel for more than 20 minutes at the injection temperature. POM-K can stay for 7 minutes at 240°C. If the machine is shut down, the temperature of the machine barrel can drop to 150°C. If the machine is to be shut down for a long time, the machine barrel must be cleaned and the heater must be turned off.