Engineering WorkshopsMachining Stock, Specified Correctly

Customer Problem

Maverick Solutions in Gujrat required low-friction custom bushes for industrial machinery, to be machined in-house. The bushes needed to run without lubrication, which immediately narrows the material choice.

Technical Investigation

The application called for dimensional stability and chemical resistance alongside low friction. Those three requirements together point clearly at PTFE: it has the lowest coefficient of friction of any solid, it is inert across the full pH range, and it absorbs effectively no moisture — so machined tolerances hold in humid or wet service where a nylon bush would swell and bind.

Root Cause

This was a specification enquiry rather than a failure. The customer had a clear engineering requirement — a dry-running, chemically-exposed, dimensionally-stable bush — and needed machining stock that would actually deliver it.

Recommended Solution

We supplied PTFE rod in the required diameters for machining. PTFE was the correct answer here specifically because the bush had to run dry: a PTFE bush needs no oil or grease, which is exactly what you want in a sealed assembly that cannot be re-lubricated, or anywhere lubricant contamination is unacceptable.

Installation Summary

The customer machined the components themselves. The guidance that matters most when machining PTFE bushes is thermal expansion: PTFE expands roughly ten times as much as steel, so a bush cut to a tight running clearance at room temperature can close up and seize once the assembly heats up. The bore should be machined to the clearance required at the operating temperature, not at ambient. Where the bush carries sustained load, PTFE also cold-flows, so a metal backing sleeve or a shouldered housing stops it creeping out of position.

Operational Result

The customer successfully machined the required components from the supplied rod.

Products Used

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