Air Compressor Piston Seal

The piston is an essential component in a compressor pump. Whether it’s an oil-free or oil-bath design, it creates compression on each stroke. In an oil-free design, a Teflon-coated compression ring provides the seal between it and the cylinder sleeve, thereby creating compression; in an oil-bath design, there are compression rings and an oil-ring, like in an internal combustion engine. Replace if the top of the piston is pitted, cracked or warped.

Performance of PTFE

PTFE has a distinctive profile that makes it one of the most precious and flexible materials available for engineering.

• Biological inertness
• Flexibility at low temperatures and thermal stability at high temperatures
• Non-flammability
• Chemically resistant – all normal solvents, acids, and bases
• Excellent weatherability
• Low dielectric constant and low dissipation factor
• Excellent insulating properties
• Low dynamic coefficient of friction
• Non-stick, easy to clean
• Broad working temperature range -180°C (-292°F) to 260°C (500°F)

PTFE properties are often enhanced using a variety of fillers creating a PTFE compound, such as a 15 or 25% glass filled PTFE, to improve wear resistance, increase part stability, and improves creep strength and reduce deformation under load in comparison with virgin grade PTFE. PTFE resin does not flow when it melts and cannot be injection molded. The best method is molding and machining.

Modified PTFE

Modified PTFE is a chemically modified version of PTFE that has new capabilities in addition to the property characteristics consistent with virgin PTFE material.

• Part surfaces are smoother, and less porous – components stay clean since they are less likely to trap contaminants
• Improved permeation resistance
• Longer flex life than PTFE
• Increased stiffness & improved creep resistance
• Higher dielectric strength yields superior high-voltage insulation
• Provides good chemical stability and broad chemical resistance