PTFE Piston Ring

A PTFE piston ring is a machined sealing ring fitted to a piston in a cylinder. Unlike metal piston rings, a PTFE ring does not require continuous oil lubrication to perform — it is self-lubricating, chemically inert, and conforms to non-round bores over the full stroke. The result is a ring that runs clean, reduces bore wear, and is compatible with gases and liquids that would attack conventional piston ring materials.

Kaxite manufactures the piston ring in pure PTFE and in filled grades — carbon, graphite, glass and bronze filled, plus pure PEEK. Filled grades are widely used in compressor service because they improve creep resistance and dimensional stability under sustained load. Rider, wearing and guide rings are also manufactured in the same range and to customer specification.

• Runs without lubrication. Operates in non-lubricated and low-lubrication conditions, so the process media is not contaminated by oil carry-over.
• Resists chemical attack. Inert to acids, bases, oxidizers and most solvents — the ring works in chemical and process gas service where metal rings would corrode.
• Reduces bore wear. Softer than metal, the ring wears before the cylinder bore and does not gall or score the running surface.
• Conforms to unround surfaces. The PTFE ring deforms to follow cylinder ovality, taper and thermal distortion that a rigid metal ring cannot follow.

Ring type

Piston ring (also Rider / Wearing / Guide)

Material

Pure PTFE, Carbon / Graphite / Glass / Bronze filled PTFE, PEEK

Nominal diameter

Custom to drawing or cylinder bore

Radial section

Per cylinder design and pressure rating

Gap type

Butt-cut, step-cut or angle-cut

Chemical range

pH 0 – 14, inert to most media

Service temperature

−200 °C to +260 °C (PTFE grades)

Lubrication

Not required — self-lubricating

Tolerance

Per customer drawing and application

OEM / ODM

Supported

Sample

Available for evaluation

Documentation

Material certificate on request

1. Ring dimensions Cylinder bore diameter, ring radial section, axial thickness, and gap type.
2. Material grade Pure PTFE for chemical and clean service; carbon, graphite, glass, bronze filled or PEEK for compressor and high-load applications.
3. Operating conditions Gas or liquid medium, pressure, temperature, stroke length and running speed.
4. Quantity and delivery Number of rings, required delivery date and destination port.
5. Documentation Material certificate, dimensional inspection report or other project-specific requirements.
6. Drawing (if custom) DWG, DXF, PDF or a physical sample for non-standard profiles and gaps.