Cable material extruder_Nine Delong Extrusion_Cable material extruder
Description:Performance and Use
PVC (PolyVinylChloride) generally has 7 levels (SG1-SG7) according to the hardness and performance of the material, and the density is about 1.4 g/cm3. Products below SG4 are generally soft products and require a large amount of plasticizer during molding. They are mainly used to make artificial leather, insulation layers for wires and cables, seals, etc. SG5 and above are hard products, mainly used to make various pipes, such as drainage, electrical, post and telecommunications pipes and pipe fittings, various plates, sheets, profiles, etc.
PVC has a molding shrinkage rate of 0.6-1.5%, good mechanical properties, excellent electrical properties, self-extinguishing properties, strong acid and alkali resistance, good chemical stability, and low price. It is a very widely used plastic. General purpose plastic. However, its use temperature is not high, with the highest temperature being around 80°C, which hinders its development. 3.2 Precautions for molding PVC is an amorphous material and has low moisture absorption. There is no need to dry before molding. If necessary, the cable material extruder can be dried at about 65°C for 2 hours. The melting temperature and decomposition temperature of PVC are very close, and its fluidity is poor. Plasticizers, stabilizers, lubricants and other additives must be added before molding. After improvement, the molding temperature range of PVC is still very narrow, about 160-190°C, and the melt viscosity is high. When the temperature exceeds 190°C, PVC will easily decompose and release HCL gas, and HCL will accelerate the decomposition of PVC. It is more likely to decompose when in contact with steel and copper at a temperature of 200°C, and corrosive and irritating gases will escape during decomposition. Therefore, low temperature, low speed and high pressure should be used as much as possible to mold PVC. It is now generally believed that PVC products are toxic. In fact, PVC itself can be said to be non-toxic. The toxicity mainly comes from various additives. The mold pouring system for producing PVC should be thick and short, the gate cross-section should be large, and there should be no dead corners. The suitable temperature of the mold is 20-50°C. When using a screw injection machine nozzle, the hole diameter should be large to prevent material stagnation in dead corners. The surfaces of the mold, screw and barrel should be chromium-plated. It is best not to use inserts. If there are inserts, they should be preheated.
PS (Polystyrene) is a commonly used transparent plastic with a light transmittance of more than 90%, second only to organic glass, and a density of 1.05g/cm3. The cable material extruder is a medium-density plastic. closest to water. It is often used to indicate the injection volume and output of an injection molding machine. It has excellent electrical insulation (especially high-frequency insulation), good colorability and water resistance, good chemical stability, and average strength, but it is brittle and prone to stress cracking. It is not resistant to organic solvents such as benzene and gasoline. Suitable for making insulating transparent parts, decorative parts, chemical instruments, optical instruments and other parts.
Precautions for molding PS is an amorphous plastic with low moisture absorption. If stored well, it does not need to be dried before molding. It is recommended to dry it at 80℃ for about 2 hours before molding. The molding temperature can be selected between 170-270℃, but The optimal molding temperature is 185-215℃. The molding shrinkage rate is 0.6-0.8%, the molding temperature range is wide, and it is not easy to decompose, but the thermal expansion coefficient is large and it is easy to generate internal stress. With good fluidity, it is advisable to use high mold temperature and low injection pressure. Extending the injection time of the cable material extruder will help reduce internal stress and prevent shrinkage and deformation. In terms of molds, various forms of gates can be used, and the gates are connected with the plastic parts in an arc to avoid damaging the plastic parts when removing the gate. The demoulding angle is large, the ejection is even, and the wall thickness of the plastic part is uniform. It is best not to have inserts. If there are inserts, they should be preheated.
When you choose our cable material extruder, you will get the quality assurance of the Jiade plastic machine brand, the flexibility to choose multiple models, the technical support and manufacturing advantages of the Bengbu origin, and the features of simple operation. Please contact us and we will provide you with more detailed product information and services to help you make a wise choice.