Email:info@eoexport.com Liaoning EO Technology Co.,Ltd

Liaoning EO Technology Co.,Ltd

Summarizing The Most Practical Processing Technology Of POM Injection
POM (also known as race steel, special spirit). It is based on formaldehyde, such as raw materials polymerization obtained. Pom-h (POM-poly), pom-k (Pom copolymer) is high density, high crystallinity of thermoplastic engineering plastics.
Good physical, mechanical and chemical properties, especially with excellent friction resistance. Pom is a crystalline plastic, the melting point is obvious, once reached the melting point, melt viscosity rapidly decline. When the temperature exceeds a certain limit or the melt heating time is too long, it will cause decomposition.
Copper is a pom-degrading catalyst, and copper or copper materials should be avoided in contact with the pom melt.
1. Plastic Treatment Pom Absorbent is small, generally 0.2%-0.5%. Normally, POM can be processed without drying, but it must be dry for wet materials.
Drying temperature of more than 80 ℃, more than 2 hours, specific according to supplier information. The proportion of raw materials used in general does not exceed 20-30%.
However, depending on the type and end use of the product, sometimes up to 100%.
2, Plastic machine selection
Pom In addition to the requirements of the screw-free zone, no special requirements for injection molding machine, general injection can be.
3, Mold and gate design The common mold temperature control is 80-90 ℃, the flow path diameter has 3-6mm,
The gate length is 0.5mm, the gate size depends on the thickness of the rubber wall, the round gate diameter should be at least 0.5-0.6 times times the thickness of the product, the width of the rectangular gate is usually twice times or more than the thickness, and the depth is 0.6 times times of the wall thickness, and the stripping angle 40′-130′ between
Exhaust system:
Pom-h thickness 0.01-0.02m, Width 3mm
Pom-k thickness 0.04mm, Width 3mm
4. Melt Glue Speed
Can be measured by air ejection method:
Pom-h can be set to 215 ℃ (190℃-230℃)
Pom-k can be set to 205 ℃ (190℃-210℃)
5. Injection speed
Common for the medium speed is fast, too slow to produce ripple, too fast prone to produce a pattern and shear overheating.
6, back pressure
The lower the better, generally no more than 200bar.
7. Residence time
If the equipment does not have glue retention point pom-h can be stranded in 215 ℃ 35 minutes, pom-k can be 205 ℃ stranded for 20 minutes, there will be no serious decomposition, in injection temperature melt can not stay in the barrel for more than 20 minutes. Pom-k can be detained for 7 minutes under 240 ℃.
If the shutdown, the barrel temperature can be reduced to 150 ℃, if you want to long-term downtime must clean the machine package, close the heater.
8, downtime The cleaning barrel must use PE or PP, turn off the electric heating, push the screw in the front position. The barrel and the screw must be kept clean. Impurities or dirt will change the thermal stability of the POM (especially pom-h). Therefore, when the use of halogen-containing polymers or other acidic polymers, the application of PE clean clean to play the pom material, or explosion will occur.
If the improper effect of pigments, lubricants or materials containing GF nylon, will lead to plastic quality.
9. Post-processing
For the very warm use of the workpiece and high quality requirements, must be heat treatment.
Annealing treatment effect, the product can be put into a concentration of 30% hydrochloric acid solution immersion 30 minutes, and then use the naked eye to determine whether there is residual stress of the crack production.
Copyright © Liaoning EO Technology Co.,Ltd All Rights Reserved.
QR Code