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　　1. Mechanics

Form and size of stress, form and time of load, anti fatigue requirements, allowable deformation, overload and accidental stress conditions, impact resistance requirements, etc.

　　2. heat

Normal operating temperature, maximum and minimum operating temperature.

　　3. environment

Contact with solvents and various vapors, chemical reaction with acid and alkali, water absorption, UV and environmental oxidation, sand and rain erosion, mold and microorganism, etc.

　　4. toxicity

Flame retardant, toner, additive or toxicity during decomposition.

　　5. appearance

Consistency and persistence of transparency, surface brightness and color.

　　6. size

Allowable error and dimensional stability, weight factor.

　　7. production

Selection of processing technology, assembly method, trimming and secondary processing, quality control and supervision.

　　8. Economics

Material cost, mold cost, processing machinery cost, auxiliary equipment cost, operation cost, machinery maintenance cost, etc.

　　9. statute

Safety regulations (flame retardant, food, medicine).

Industrial regulations (automobile industry, electronic industry, etc.).

　　10. General structural parts

Requirements: there are no special requirements for strength and heat resistance. It is generally used to replace steel or other materials, with large batch and high productivity. The cost is low, and sometimes there are certain requirements for appearance.

Application: electronic parts, electrical (machine) shell, stationery, daily necessities, toys, instruments, fasteners.

Materials: low pressure polyethylene (HDPE), polyvinylidene chloride (PyC), modified polystyrene (20a, 204), ABS, polypropylene (PP).

　　11. Transparent frame

Requirements: same as above, with good transparency.

Application: lampshade, instrument lens, toy, optical lens.

Materials: acrylic PMMA, modified polystyrene (204203a), polycarbonate (PC), GP, San, ABS, and polypropylene (PTFE, F-4).

　　12. Wear resistant stressed transmission parts

Requirements: high strength, rigidity, toughness, wear resistance, fatigue resistance and thermal stability.

Applications: bearings, gears, racks, turbines, cams, rollers, couplings.

Materials: nylon, MC nylon (monomer cast nylon), Polyoxymethylene (POM), polycarbonate (PC), polyether (PPO), linear polyester, polyphenoxy. The tensile strength is above 58.8kpa, and the working temperature is 80-120.

　　13. Antifriction self-lubricating parts

Requirements: small force, fast movement speed, low friction coefficient, high wear resistance and good self lubrication.

Application: piston ring, mechanical seal ring, sliding guide rail, bearing.

Materials: Poly maple (PSU), POM filled with F-4, poly (perfluoroethylene propylene) (F-46), low pressure polyethylene (HDPE).

　　14. High temperature resistant structural parts

Requirements: working at high temperature, with high thermal deformation temperature and high temperature creep resistance, and high temperature wear resistance, corrosion resistance and electrical insulation.

Application: high temperature structural transmission parts, gears, bearings, piston rings, pumps, valves, class B, F, h, C electrical insulation parts.

Materials: Poly maple (PTFE, F-4), with phenyl ether, poly (perfluoroethylene propylene) (F-46), etc.

　　15. Corrosion resistant parts

Requirements: good corrosion resistance to acid, alkali and organic solvents.

Application: chemical pipeline, container, etc.

Materials: polymaple (PSU), F-4, polyvinylidene chloride (PyC), polypropylene (PP).

This article is from Jiangmen Engineering Plastics:http://yzw188.cn/