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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

Touch the conditions of solvents and various vapors, chemical reaction with acid and alkali, water absorption, UV and environmental oxidation, sand and rain corrosion, mold and microorganism.

　　4. toxicity

Flame retardant, toner, additive or toxicity during decomposition.

　　5. appearance

Transparency, appearance brightness, consistency and persistence of color.

　　6. scale

Allowable error and scale stability, weight factor.

　　7. production

Selection of processing technology, installation 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 rules (flame retardant, food, medicine).

Industrial rules (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. The batch is large and high productivity is required. Low cost, sometimes have certain requirements for appearance. 　　

Source: Jiangmen engineering plastics http://www.jzxhuodongfang.com/