Sheet in PTFE 1200x1200 mm natural

PTFE is the fluoroplastic you pick when ordinary engineering plastics give up. The material is inert to practically every chemical found in industry, handles continuous service up to 260 degrees and keeps its mechanical properties down to minus 200 degrees. The friction figure is among the lowest that exists in solid form, which makes PTFE the first choice for sliding surfaces that have to cope with dry running or contact without lubricant. The density is 2.17 g/cm³, considerably higher than polyolefins and technical nylons, which you notice when handling thicker sheets.

The sheet format opens up milling and turning of parts where the blank needs to be bigger than a round rod can give. The workshop cuts gaskets, slide rails, sealing rings, wear plates, shims and tank lining straight out of the sheet. PTFE is soft compared with technical plastics such as POM and PA, so machining is done with sharp tools, moderate feeds and no impact loading. The sheet can be cut on a band saw, milled in normal gantry machines and worked on an ordinary lathe, but the chips are feather-light and need to be led away with extraction. On large workpieces, temperature compensation matters; PTFE has relatively high thermal expansion and the sheet should be allowed to settle at workshop temperature before the measurements are taken.

Chemically, PTFE works as the reference point when other plastics are judged. Concentrated acids, alkalis, organic solvents, oxidizing media and process gases pass by without attacking the material. That is why PTFE sheets are used as lining in chemical tanks, as base plates in blow-cleaning benches and as shims where the process medium would destroy ordinary plastic or rubber. The low surface energy means dirt and process products do not stick; a PTFE-covered surface stays clean longer than a metal surface and is easier to clean between batches.

Mechanically, PTFE is not a structural material in the same sense as POM or PEEK. The material creeps under load, which means bolted joints need metal sleeves or spacer washers and that gaskets have to be designed to compensate for the change of shape over time. In static sealing this is rarely a problem; under dynamic load, bearings and sliding surfaces have to be dimensioned with margin. For applications with higher PV values there are compounds with carbon, glass or bronze mixed in. Impact strength is good even at low temperatures, which makes PTFE useful in cryogenic installations where other plastics turn brittle.

The heat resistance makes PTFE useful in oven glass, high-temperature gaskets and in processes where the surroundings swing between cold and heat. The material is rated V0 to UL 94 and does not give off smoke until very high temperatures. That means a PTFE sheet can stay in a system that fails thermally without adding to the fire, which is valuable in process equipment, lab fittings and electronics enclosures. The dielectric properties of the material are stable across a wide frequency range as well, which makes thin PTFE sheets useful as electrical insulators in high-frequency applications.

The sheet comes in the natural white, semi-transparent shade that is the own color of PTFE. Thicknesses run from thin films for seals up to heavier sheets used as blanks for milled parts. You pick the thickness from the finished size of the part, plus a few tenths for machining allowance. Large surface formats are available for lining tanks and vessels where it matters to keep the number of joints down.

Bear in mind that PTFE is not bonded or welded by ordinary methods. Mechanical fastening, clamping or TIG welding with a PTFE rod are the workable routes. The surface is also hard to print or paint on without an etching pretreatment, which is rarely a problem in technical applications but worth knowing if the sheet is to be marked with permanent text or a logo. When mounting with bolts, through-going metal sleeves are the preferred choice to take up the preload, so the PTFE material does not creep and wreck the joint.

For food and pharmaceutical use there are matching PTFE grades approved to FDA and EU 10/2011 rules. Always make sure the right grade is specified on the order if the sheet is going to be in contact with product; that specification is not visible on the sheet itself but is confirmed on the order.

Do you need help picking the right PTFE grade, thickness or filler for your application? Get in touch and we will go through it before a quote.

The 1200x1200 mm format in natural is enough for several seals and slide washers out of one and the same sheet.