PEEK or Copper in a Stenter Chain

What PEEK Is

PEEK, polyether ether ketone, is a high-performance special thermoplastic. It combines high temperature resistance, wear resistance, self-lubrication, low noise, corrosion resistance and high strength, and that combination is why it has spread so widely through textile machinery.

Self-lubrication is the property that matters most on a stenter. A part that does not need an oil film is a part that cannot contaminate fabric, and that is worth a great deal on a finishing floor.

The Bush Job PEEK Took Over

Inside a chain, the bush is the wear-resistant lining between the pin and the chain link. It used to be a copper mesh lining. PEEK replaced it because, being self-lubricating, it is more wear resistant and has a longer service life.

There is a second benefit that mills notice at overhaul time. The bush can be changed easily, so a chain body with sound link plates does not have to be scrapped when the bearing surfaces wear. That turns a chain replacement into a bush change.

Slider Material Is a Real Choice

The slider is the part that runs against the guide rail and carries the drag of the whole chain. Here copper and PEEK are genuine alternatives rather than one replacing the other.

Copper takes higher load and is the traditional build. PEEK runs lighter and quieter, does not need the same grease film, and puts less drag on the rail. Heavy fabric at high tension favours copper. Lighter goods at high line speed favour PEEK, which is why the same Artos chain body is offered with either.

Dust Covers Are Where Chains Really Fail

In a dusty mill the bush is rarely the first thing to wear out. What happens is that fibre lint and finishing chemistry pack into the bearing surface and grind the pin.

A PEEK dust cover keeps that out. On Monforts chains it is the difference between a chain that reaches its overhaul interval and one that does not, and it is why the PEEK bush and dust cover build is worth its higher price anywhere fibre dust is heavy.

Where Else PEEK Turns Up

Two more places. The adjustable nut on the lead rod, the part that lets the guide rail be widened, is PEEK on modern machines because it is self-lubricating and needs no molybdenum disulfide, and because it is not easy to break under adjustment load.

And the buffer block in the chain path, where PEEK's high strength and low noise absorb impact without cracking at chamber temperature.