Hollow Bar in PTFE GF25 2000 mm natural

Tubes in PTFE GF25 give you the chemical resistance and the low friction of PTFE, but with an addition of 25 percent glass fiber that raises the stiffness and damps the cold flow that pure PTFE is otherwise known for. The tubular format is practical when you need a sleeve, a plain bearing, an insulating bushing or a chemically resistant line for media that eat most other plastics apart.

The material handles 260 degrees continuously and takes shorter exposure even higher, while it works all the way down toward minus 200 degrees. The density sits around 2.2, which is high for a thermoplastic and comes from the fluorine content. The flammability rating is V0 per UL 94, which means the material goes out by itself when the flame is taken away. Water absorption is negligible and the material is resistant to practically all industrial chemicals, from concentrated acids and strong bases to organic solvents. Only molten alkali metal and elemental fluorine attack it in normal service environments.

The coefficient of friction is among the lowest found in solid materials. That means a tube in PTFE GF25 can be used as a dry running bearing sleeve or slide bushing without lubrication, which is valuable in environments where oil or grease is not allowed. The role of the glass fiber is to raise the PV value (pressure times sliding speed) and reduce the creep that unfilled PTFE shows under static load. That makes the material considerably more dimensionally stable over time under load, which is decisive for seals and bushings in continuous operation.

Common uses for tubes in this grade are plain bearings in chemical process pumps, insulators in high temperature equipment, sleeves around aggressive media tubes, piston rings in compressors and sealing elements in valves. The material handles both wet and dry environments and is unaffected by UV radiation and ozone, which makes it usable outdoors or in ozone rich processes as well. The white, slightly opaque color is typical of filled PTFE and does not change over time.

In machining, PTFE GF25 cuts easily on a lathe and a mill, but calls for sharp tools and preferably a low feed. The glass fiber wears the edges, so carbide or diamond coated inserts extend the life. The material cannot be bonded in the ordinary way; if you are going to join PTFE the surface has to be etched or mechanically roughened. Welding is not an option for fluoropolymers in this class. Remember too that PTFE expands more strongly than steel with temperature changes, which matters for a fit in a metal housing.

We supply the tube in standard lengths and cut to the dimensions you need. Inner diameter, outer diameter and tolerance are chosen to suit the application. For a plain bearing bushing you often want a running fit against the shaft with enough clearance for thermal expansion; for a chemically resistant line a tighter fit is enough. If you need help choosing the right grade or dimension, get in touch and we will go through the requirements together.

At double the length, 2000 mm in natural, the bar is enough for several dimensionally stable rings without a joint.