A guide ring, the support ring is also called, is a hydraulic cylinder for the piston or the rod or the cylinder, the piston or the piston rod movement of the supporting parts, which can prevent the movement of the piston or the piston rod of the cylinder occurs during direct contact and friction, or protect the cylinder and the piston rod without being damaged effect. Materials commonly used for the guide ring polyoxymethylene (POM). Material properties Bakelite is a hard and brittle thermosetting plastic, commonly known as bakelite high mechanical strength, tough abrasion resistance, dimensional stability, corrosion resistance, excellent electrical insulation properties. Suitable for the production of electrical insulation body parts, instruments can be use in hot and humid conditions forming properties 1 formability is better, but the general contraction and directional amino plastic than large, and contains water volatiles. should be preheated before molding, molding process should exhaust, no warm-up should improve mold temperature molding pressure. larger 2 die temperature effects on liquidity, while generally more than 160 degrees, liquidity will decline rapidly. 3 hardening speed is generally slower than the amino plastics, hardening heat released when a large Large thick-walled plastic parts The internal temperature is easy too high, uneven and prone to overheating Bakelite hardening guide ring: main guide.