Polyethylene Terephthalate Machining 5-Axis Milling, Turning, Drilling.

Polyethylene Terephthalate (PET) is a thermal unreinforced semi-crystalline polyester, showing dimensional stability similar to acetal resin and a wear resistance similar to nylon. It is ideal for precision mechanical parts with high loads and abrasive environments. PET was the first commercial polyester, synthesized in 1945 and introduced to the market soon after.

PET has an excellent property-cost ratio and, in particular, good mechanical properties, excellent electrical properties, and resistance to solvents. PET has a low tendency to absorb moisture, low thermal expansion, high mechanical strength, creep and wear resistance, good electrical insulation, and chemical resistance. It is most suitable for the construction and use of moving parts, even in wet applications. It does not absorb CO2 and has an excellent aesthetic quality. PET (PETP in the past) is a partially crystalline thermoplastic polyester based on polyethylene terephthalate. The hot water resistance is low but has better resistance to acids than nylon or acetal.

PET can work continuously at 100 °C, and its melting point is 70 °C higher than acetal resin. It retains most of its original strength up to 85 °C, more than nylon or POM. PET is FDA compliant and is available in natural and black coloration, under FDA regulation 21 CFR 177.1630 for food contact. PET’s compatibility with food is allowed in the European Commission Directive 2002/72/EC and its amendments (2004/19/EC).

Many components and machine parts in the food industry use PET because it is easily cleaned with the most common cleaning products (previously, the most common material was aluminum). Its rigidity and hygienic properties – as well as dimensional stability and resistance to hydrochloric acid – make PET an ideal choice for various components in the pharmaceutical industry (previously, the most common material were Nylon and PEUHMW).

PTFE + PET is a PET admixed with a solid lubricant (PTFE), which provides a higher resistance of use and a lower friction coefficient. This material has excellent dimensional stability and remains rigid at elevated temperatures, and is FDA compliant.

Applications in the Mechanical, Food, Chemical, and Electrical industries

This material is particularly used for sliding bearings, slides, guides, etc. because it has a low coefficient of friction. The dimensional stability makes it irreplaceable for precision parts with tight tolerances, even in humid environments or in presence of a heat source.

It is physiologically inert and widely used in the industry of machinery in the food industry.

PET is used as insulation for electrical applications because it has constant electrical characteristics.
It also has good resistance to acids and chlorinates.

Applications

Mechanical This material is particularly used for sliding bearings, slides, guides, etc. because it has a low coefficient of friction. The dimensional stability makes it irreplaceable for precision parts with tight tolerances, even in humid environments or in presence of a heat source.
Food It is physiologically inert and widely used in the industry of machinery in the food industry.
Electrical PET is used as insulation for electrical applications because it has constant electrical characteristics.
Chemical It also has good resistance to acids and chlorinates.

main characteristics

Excellent dimensional stability
High mechanical strength, hardness, stiffness
Stability very good color
Excellent wear resistance
Good sliding properties
Low water absorption
Low thermal expansion
Good electrical insulation properties
Excellent stain
Suitable for food contact
Good workability

Defects

Material very hard
Low impact resistance

Applications of Polyethylene Terephthalate

Sprockets, bushings, gears, cams, spindles, manifolds, power
piston pumps, valves and valve bodies, tracks, electrical
insulators, screws, components, fuel pump, plugs and rotors
food system … etc..