Round Rod in PEEK Mod 3000 mm black

PEEK Mod in round rod is modified PEEK with PTFE, graphite and carbon fiber blended into the base polymer. The rod handles 260 degrees continuously and peaks up to 300 degrees, has a V0 fire rating and a very low water absorption of around 0.03 percent. The modifying additive lowers the coefficient of friction against the mating surface and gives lower wear in dry running or poor lubrication. The thermal conductivity is around 0.82 W/mK, noticeably above pure PEEK, which helps carry frictional heat away in bearing positions.

Mechanical figures: density around 1.44 g/cm³, tensile strength around 84 MPa, ball indentation hardness close to 250 MPa and impact strength about 28 kJ/m². Those are lower values than pure PEEK in most respects, but that is not the whole picture. In practical operation, where bearings run against steel at temperatures that would have worn out other polymers in hours, PEEK Mod is often the winner on service life.

The round rod format is made for turning shafts, rings and bushings. Typical parts are plain bearings in high temperature environments, gears that have to run without lubrication, shafts in pumps and mixers that run hot, thrust loaded parts in furnace equipment and bushings in designs where lubricants are not welcome (food machinery, vacuum chambers, semiconductor fixtures). The ability to run without external lubrication is central; the PTFE and graphite additive builds a transfer film on the mating surface that carries the load.

Which mating surface the bearing or the shaft runs against matters a great deal. PEEK Mod against hardened and ground steel gives the best results with a high surface finish and moderate loads. Against surfaces with higher roughness the wear increases. When sizing, count on the run in giving an initial wear that then stabilizes once the transfer film has built up. Contact surface pressure and PV value govern the design; PEEK Mod takes considerably higher PV than pure PEEK but has limits. Get in touch if you want to talk through a specific load case.

Chemically the material takes most solvents, oils, alkaline cleaning agents and diluted acids. For hot concentrated acids, concentrated sulfuric acid and certain fluorine compounds another polymer is recommended. The water absorption is so low that the rod keeps its dimensions even in a damp environment.

Machining is done with carbide. Thanks to a lower carbon fiber content than in the CF30 grades, the tool life is longer and the chip formation more even. Sharp cutting angles, moderate cooling and stable clamping give fine surfaces. For shafts that are to run in bearings, the surface finish at the bearing position matters more than the perfect tolerance span. Grinding dust should be extracted and handled with respiratory protection.

The rod is stocked in several diameters and cut to the length you want. If you need to talk through the choice of grade (Mod, CF30, pure PEEK), get in touch.

At the full length of 3000 mm, black Mod gives many blanks for turned plain bearings and bushings per rod.