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Plastic Identification

Plastic Identification:




Repair procedures for plastics will vary depending on the type of plastic. In order to identify the type of plastic, look for the SAE code stamped into the part:

Code Found
^ Match the code to those in the plastic identification chart to determine whether the plastic is thermoplastic or thermoset plastic, and whether the plastic is rigid or flexible.
^ Identify any special handling procedures.

Do not use a plastic burn test in order to distinguish the types of plastics. The burn test produces vapors that are harmful to you.

No Code Found
^ Type the plastic part as thermoplastic if the part has the following characteristics:
- Heat sensitive
- Will burn
- Solvent sensitive
^ Type the plastic as thermoset plastic if the part has the following characteristics:
- Not sensitive to heat
- Will not melt
- Will smolder rather than flame up
- Normally not solvent sensitive

Thermoplastic and thermoset plastics can be either rigid or flexible. Thermoplastic plastic parts are best repaired with a hot iron plastic material-feed welder, but are usually replaced. Thermoset plastic can be repaired with epoxy or other more rigid two package repair material.