Hollow Bar in PTFE GF20 2000 mm natural

Tubes in PTFE GF20 combine the most valuable properties of PTFE, chemical inertness and low friction, with what the glass fiber contributes in dimensional stability and wear resistance. The 20 percent filling is a good middle ground for the tubular format, where purity and stiffness have to be balanced.

As a base material PTFE is close to immune to chemical attack. Acids, bases, solvents, oils, fuels, most of it passes without a reaction. The flammability rating is V0, the continuous service temperature 260 degrees and the material keeps its properties all the way down to minus 200 degrees. Water absorption is negligible and the density sits around 2.17 g/cm³ for the filled material.

20 percent glass fiber removes the biggest practical weakness of PTFE under pressure and temperature: creep. A tube in pure PTFE clamped between flanges tends to flow over time; with glass fiber reinforcement the shape is kept. The wear resistance in contact with rotating or reciprocating shafts also improves substantially.

Applications for the tubular format:

Slide bushings and guide sleeves in pumps, compressors and cylinders.

Short sections in the chemical process industry where the tube material is in contact with aggressive media.

Bearing and support sleeves in high temperature environments.

Insulating and sealing sleeves around thermocouples or dosing tubes.

The color is grayish white. Machining works in the ordinary machines of a metal workshop, but the glass fiber wears edges, so carbide tipped tools give the longest life. Sawing with a fine toothed blade goes fine; turning calls for sharp inserts and a controlled feed to avoid the glass fiber tearing the surface. PTFE cannot be bonded in the ordinary sense; surface activation (etching) is needed if a chemical joint is to be used. Mechanical couplings and clamped joints are standard.

Remember that thermal expansion is higher for PTFE than for metal. When installing between steel components the tube needs room to move, otherwise dimensions can lock up during hot cycles.

Get in touch if you need help choosing between GF15, GF20, GF25 or another modification. Different filler contents suit different loads and environments.