Bronze-Filled PTFE Bush — why this filler for this component
A bush is a PV problem — contact pressure multiplied by surface speed — and bronze filling raises the PV a PTFE bush will survive further than any other common filler. It does that in two ways at once: the metal particles carry load the polymer alone would cold-flow under, and they conduct frictional heat out through the bore instead of letting it accumulate at the contact.
Where Bronze-Filled PTFE Bush is used
Against a glass-filled bush
bronze carries more load and sheds far more heat, so it wins on hot, heavily loaded, dry-running duty. Glass-filled wins the moment the fluid turns aggressive, because glass filling keeps most of PTFE’s chemical resistance while bronze forfeits it.
End of life is bore wear past the drawing clearance limit. Because bronze conducts heat well, a bronze-filled bush tends to wear steadily rather than failing suddenly, so measured bore checks at service intervals are a reliable way to plan replacement.
Key properties
Compound
Bronze-Filled PTFE, typically 40% bronze in 60% PTFE
How it works here
Heat is the real enemy in a dry bearing. PTFE has poor thermal conductivity, so a heavily loaded unfilled bush runs hot at the contact face, softens and wears rapidly. Bronze gives the heat a path out through the bush wall into the housing, which is why bronze-filled bushes hold up at pressures and speeds where unfilled and glass-filled grades fade.
Where it does not belong
The bronze is chemically exposed. This is a mechanical bearing grade, not a chemical one — acids, steam and oxidising media attack the filler even though the PTFE around it is unaffected. It is also no longer non-stick or food-safe, so it does not belong anywhere the bronze could contaminate a process fluid.
Specifications
| Property | Value |
|---|---|
| Compound | Bronze-filled PTFE, typically 40% bronze |
| Duty | Radial load, dry running, high PV |
| Inner Diameter | To drawing — commonly 5 mm to 300 mm |
| Counterface | Ground, hardened shaft recommended |
| Governing factor | PV limit and heat path through the wall |
| Not suitable for | Acids, steam, oxidisers, food contact |
Manufacturing process
Compression moulded from 40% bronze in 60% PTFE compound, sintered, then machined to your drawing. Filled compounds need higher compaction pressure than unfilled PTFE to reach full density through the section.
Material selection notes
Heat is the real enemy in a dry bearing. PTFE has poor thermal conductivity, so a heavily loaded unfilled bush runs hot at the contact face, softens and wears rapidly. Bronze gives the heat a path out through the bush wall into the housing, which is why bronze-filled bushes hold up at pressures and speeds where unfilled and glass-filled grades fade.
How to specify your order
Against a glass-filled bush: bronze carries more load and sheds far more heat, so it wins on hot, heavily loaded, dry-running duty. Glass-filled wins the moment the fluid turns aggressive, because glass filling keeps most of PTFE’s chemical resistance while bronze forfeits it.
Quality checks and inspection
Dimensions are verified on CMM against your drawing. Filler content and sintered density are checked per ASTM D792, with tensile and elongation per ASTM D4894. A mill test certificate stating the lot, filler content and measured values ships with the order.
Ordering and export documentation
Set running clearance for the hot condition, not the bench measurement. Filled PTFE expands considerably, and a bush fitted to a cold clearance can nip the shaft once the bearing reaches running temperature. A ground, hardened shaft will roughly double the service life over a soft turned one.
Export packing and lead time
HEMSUN is a DGFT IEC registered exporter (Government of India). Commercial invoice, packing list and certificate of origin accompany international despatch.
Storage and handling
End of life is bore wear past the drawing clearance limit. Because bronze conducts heat well, a bronze-filled bush tends to wear steadily rather than failing suddenly, so measured bore checks at service intervals are a reliable way to plan replacement.
Compliance & Standards
HEMSUN is a DGFT IEC registered exporter (Government of India). Filler content and sintered density are verified per ASTM D792 on each batch, with tensile and elongation checked per ASTM D4894.
Frequently Asked Questions
What Bronze-Filled PTFE Bush options does HEMSUN manufacture?
A bush is a PV problem — contact pressure multiplied by surface speed — and bronze filling raises the PV a PTFE bush will survive further than any other common filler. It does that in two ways at once: the metal particl…
Can you supply Bronze-Filled PTFE Bush for OEM and export orders?
Yes. We support prototype lots, recurring OEM programmes, and export packing with material certificates and dimensional inspection reports on request. Typical RFQ response is within one business day when drawings are complete.
How do I request a quote for Bronze-Filled PTFE Bush?
Send material grade, dimensions or drawing, quantity, application media, and operating temperature/pressure via https://hemsun.com/contact. Our engineering team confirms manufacturability, lead time, and pricing.
