Bearings, linear positioning assemblies, sliding components, connectors, seals and drug delivery devices in medical instruments are often challenged by friction and wear, material compatibility, assembly force and repeated sterilisation cycles. One major difficulty is that a single moving part may undergo different sterilisation processes sequentially, such as high-temperature steam sterilisation followed by low-temperature ethylene oxide sterilisation.

Lubricants must keep mechanisms operating reliably and continue meeting instrument design requirements after exposure to high-temperature moist heat or low-temperature chemical / radiation sterilisation. Leveraging the NYEMED product line, comprehensive testing capabilities and application engineering support, FUCHS helps customers develop lubrication solutions compatible with both high‑ and low-temperature sterilisation, spanning material screening through to process validation.

I. Why Sterilisation Processes Change Lubricant Selection

Unexpected friction or wear may occur at any stage of a medical device lifecycle: proof of concept, design verification, production ramp-up and field trials. Friction and wear degrade device performance. Beyond friction reduction, lubricants also serve sealing, motion control, damping and assembly aid functions.

When components undergo repeated sterilisation, grease is subjected to vastly different temperature and environmental conditions. High-temperature sterilisation involves humid heat and high pressure, while low-temperature sterilisation exposes lubricants to chemical media or radiation. Evaluating only initial torque or visual appearance at ambient temperature is insufficient. The sterilisation temperature range, sterilisation method, number of cycles, contacting materials, dispensing location and service-life requirements must all be included in validation assessments.

High-temperature sterilisation is typified by autoclaving, a demanding hot-wet service condition. Lubrication for low-temperature sterilisation compatibility most commonly targets ethylene oxide (EtO) processes; some applications also require gamma radiation assessment. The NYEMED range has undergone sterilisation stability testing for mainstream methods including autoclaving, ethylene oxide and gamma irradiation. (Test data helps narrow candidate selections; final confirmation of specific products, formulations, substrates and parameters must be performed on the actual device.) This supports early-stage selection for applications requiring compatibility with both high‑ and low-temperature sterilisation.