Why Do O-Ring Seals Need Lubrication?

Lubricating an O-ring is an important part of the assembly line process as it can help protect an application from abrasion or scuffing damage. Applications that are constantly in motion are prone to this wear over time. The addition of a lubricant can extend the operating life of the O-ring by creating a barrier film over its surface. This barrier film can also help reduce leakage by filling the asperities between the metal surface and the O-ring seal.

These benefits can be seen in Nye’s Case Study, featuring KOSME, a company that designs and manufactures a full range of bottling and beverage line equipment for filling, labelling, and stretch blow molding. The company was looking to replace an existing grease with an H1 incidental food contact product to lubricate the O-ring seals of a pneumatic cylinder. The cylinder is a rotating piece of equipment that requires all seals to survive hundreds of thousands of cycles. The seals are made of EPDM elastomer and require good material compatibility from a lubricant. KOSME reached out to our Channel Partner in Italy, Technolube Seal, to find a compatible grease.

Tecnolube Seal recommended Fluorocarbon Gel 880FG and GLEITMO SIL 885FG to KOSME for evaluation as they are two H1 certified lubricants that provide excellent water and oxidative resistance over a broad temperature range. Both products were tested to make sure each eliminated stick-slip friction on the cylinders. The cylinders were lubricated with the 880FG and 885FG and cycled for several hundred thousand repetitions. Following testing, the cylinders were evaluated for smoothness (no stick-slip) and wear on the seals. Each product was subjected to an accelerated aging test to ensure the seals would last the expected life time of the application.