Solid PTFE O-Rings
The ring body is PTFE, without an elastomeric core. “Solid” describes the construction; it does not mean virgin or unfilled PTFE. The specified grade and sealing arrangement both need review.
BY MATERIAL
PTFE O-Rings
FLUID accepts orders for solid PTFE O-rings. We review the material grade, dimensions, gland and operating conditions with you, and confirm supply conditions for the particular requirement.
Request a Technical Review
Initial response within 12 hours.
01 / PTFE O-RING REQUIREMENTS
Confirm the Product Construction
Solid PTFE, PTFE-coated and FEP/PFA encapsulated O-rings have different structures and sealing behaviour. Confirm the construction before comparing materials or replacing an existing seal.
FEP/PFA Encapsulated O-Rings
These combine an elastomeric core with an FEP or PFA outer jacket. The jacket and core contribute differently to the seal’s performance. They are not solid PTFE O-rings.
PTFE-Coated O-Rings
These are elastomer O-rings with a PTFE surface coating. The coating does not turn the complete ring into a solid PTFE seal or provide the same construction as an encapsulated O-ring.
02 / PTFE O-RING REQUIREMENTS
How Solid PTFE Seals Behave
PTFE is a thermoplastic with less elastic recovery than rubber. A solid PTFE O-ring develops sealing contact through controlled deformation within a suitable gland. It cannot be assumed to maintain contact force or accommodate movement in the same way as an elastomer O-ring.
Under sustained loading, PTFE can undergo time-dependent deformation, commonly described as creep or cold flow. This can change the ring’s shape and sealing contact force over time. Material grade, temperature, loading, gland restraint and service duration therefore need to be considered together.
Temperature changes also affect dimensions and contact conditions. A seal that fits during assembly may behave differently during heating, cooling or repeated operating cycles. Replacing a rubber O-ring with PTFE requires a separate review of the gland and operating conditions.
This page primarily addresses appropriately designed static face and flange seals. Radial static seals and dynamic applications require separate assessment. PTFE’s low-friction characteristics alone do not establish that an ordinary solid PTFE O-ring is suitable for reciprocating or rotary service.
03 / PTFE O-RING REQUIREMENTS
Choose the PTFE Grade for the Requirement
Virgin PTFE
Virgin PTFE is made from non-reprocessed resin without intentionally added fillers. It offers broad chemical resistance, but compatibility with the actual media and deformation under load still require review.
Filled PTFE
Fillers can change creep resistance, wear behaviour, strength and thermal properties. Examples include glass, carbon, graphite and bronze, but different fillers and contents produce different trade-offs. They can also affect media compatibility and the mating surface.
Modified PTFE
Modification of the base polymer can alter deformation and recovery behaviour. Modified PTFE does not simply mean filler-added PTFE, and it is not automatically the best choice for every sealing arrangement.
These examples describe material options for evaluation, not a confirmed FLUID stock or supply range.
Share the exact grade or material specification where available. Chemical compatibility must cover the complete compound, including fillers, and the actual process and cleaning media. General PTFE properties do not establish a finished seal’s temperature rating or suitability for every chemical.
Food-contact, pharmaceutical or other compliance requirements must be checked against the exact material and available product documentation. Material grade, dimensions and supply conditions are confirmed for the particular order.
04 / PTFE O-RING REQUIREMENTS
Gland Design and Installation Limits
Review the gland geometry, ring dimensions, tolerances, compression, clearances and sealing surfaces together. Pressure, temperature changes and long-term deformation can affect sealing contact; they should not be treated as independent maximum ratings.
Check the assembly path before selecting the ring. Passing over a shaft, shoulder, thread or sharp edge can require stretching or deformation that does not recover like rubber. Gland accessibility and available assembly space may influence the seal construction or installation approach.
Avoid cuts, scratches and distortion during handling and assembly. Do not directly apply rubber O-ring stretch or squeeze percentages to solid PTFE. Installation limits must be established for the specified grade, dimensions and seal design.
For an existing installation, provide the gland drawing and the reason for replacement, including leakage, chemical exposure, temperature cycling or assembly damage. This helps determine whether a solid PTFE O-ring is appropriate or whether another seal construction should be considered.
05 / REVIEW
Share What You Already Have
You do not need a complete specification to begin. Share the information available so we can clarify what is needed next.
- 01
Drawing, inside diameter, cross-section, units, tolerances and quantity.
- 02
Specified PTFE grade, filler type or existing material and part reference.
- 03
Gland drawing, clearances, assembly method and static or dynamic operation.
- 04
Media, concentration and cleaning conditions.
- 05
Pressure, continuous temperature, short exposures and operating cycles.
- 06
Existing seal construction, service history, replacement concern and required material or inspection documentation.
06 / RELATED PATHS
Continue the technical discussion
07 / TECHNICAL REVIEW FAQ
PTFE O-Ring Questions
How does a PTFE O-ring differ from a rubber O-ring?
PTFE has less elastic recovery and different deformation behaviour. A solid PTFE ring is not assumed to be a direct replacement in an existing rubber O-ring gland. The gland, installation method and operating conditions require separate review.
Does solid PTFE mean virgin PTFE?
No. Solid describes the ring construction. Virgin, filled and modified describe material options. The exact grade must be specified or selected against the application.
Why does creep matter in a sealing application?
Sustained loading can gradually change the ring’s shape and sealing contact force. Temperature, loading, time and gland restraint influence this behaviour, so initial fit alone does not establish long-term sealing reliability.
How should I choose between virgin and filled PTFE?
Consider the media, loading, temperature, wear conditions and mating surface. A filler may improve one property while limiting another. Provide the existing specification or application details rather than selecting on the PTFE name alone.
Which applications are considered for solid PTFE O-rings?
Appropriately designed static face and flange seals are a principal direction for review. Radial static and dynamic applications require separate assessment; other PTFE seal constructions may be more appropriate for movement or changing contact conditions.
What should I check before installation?
Confirm the gland, dimensions, assembly access and whether the ring must stretch over any feature. Avoid sharp edges and excessive deformation. Use installation requirements established for the particular material and seal design, rather than general rubber O-ring percentages.
Can FLUID review a drawing or an incomplete specification?
Yes. Share the drawing, sample or existing part information, quantity and operating conditions. We can clarify the material, dimensions and documentation required, then confirm the applicable supply conditions.
NEXT STEP
Discuss Your PTFE O-Ring Requirement
Send the information available. We will review the product construction, material and application, and clarify the next information needed.
Request a Technical Review
Initial response within 12 hours.