Creep
Continuous load
Unfilled PTFE creeps under continuous compressive load. A gasket or pad brief still needs the buyer to state thickness and the duty; this desk will not invent a compressive strength.
expanded ptfe sheet
Check whether a quoted item genuinely satisfies expanded ptfe sheet, or only resembles it. PTFE Sheet Sourcing does not certify a factory and does not reprint a hardness, thickness or density as its own.
Verification path before anyone treats the offer as the request
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Name the method
Ask which published figure and which standard were used to state color/finish and the applicable ASTM or equivalent method. A cell that only says “PTFE” is not a method.
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Separate look-alikes
Skived plate, molded ptfe sheet and expanded ptfe sheet can share a family name and still be different goods. The factory has to say which construction is on the invoice line.
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Re-check a model change
If the supplier proposes a different expanded ptfe sheet model, re-issue thickness, width and sheet size, density in g/cc if used, color/finish and the method. Do not keep the old line number.
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Keep the lot file
A plant ISO file does not stand in for the lot. Food-contact or REACH statements must name the quoted configuration.
Limits that stay on an expanded line
When a buyer asks for tensile strength (MPa), elongation at break (%), or an operating temperature in °C, write the figure and the method together. Industry datasheets often discuss PTFE near 10-25 MPa tensile or continuous service well above 150°C, but those cells belong to the named supplier page, not to this desk.
Melt
Joining method
PTFE is not melt-welded like PE or PP. If the project assumed a welded liner, that assumption has to be written down as a different construction.
Fill
Purity vs wear
Filled grades trade chemical purity and dielectric behavior for wear. Treating a carbon-filled pad as virgin ptfe sheet is a new request.
Document types, not partner logos
Color / finish page
Natural, black or a named color; skived vs expanded surface.
Cited method
The published figure and the standard used for that figure.
Thickness and size
Inches or millimetres plus finished width and sheet size.
Lot file if requested
Food-contact or REACH only when the lot is named.
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Quoted construction named on the invoice line
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Published figure plus the standard behind it
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Axes re-checked after any model change
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Site-owned certificates or hardness reprints
Send the quoted line you want checked
Include the factory’s wording next to your request wording. We will list gaps; we will not invent a match.
Review Specifications How we read a quote