By fully rubber-coating the EC end cap, we introduce micro-flexibility into the static joint. Our caps are injection-molded utilizing a high-density Nitrile Butadiene Rubber (NBR) matrix. This formulation is explicitly engineered to handle continuous exposure to standard mineral-based gear oils, petroleum greases, and synthetic lubricants at operating temperatures up to 100°C. The rubber jacket acts as a permanent vibration dampener, ensuring the plug will not vibrate loose over the lifespan of the equipment, while also providing complete immunity against external atmospheric rusting.

Striking the center of the 12*4mm cap will cause the internal metal skeleton to “dish” or cave inward. This deformation instantly pulls the outer diameter away from the bore wall, destroying the interference fit and guaranteeing a static oil leak. Technicians must use a flat installation mandrel that applies force evenly across the extreme outer edge of the seal. Furthermore, wiping a very light film of system-compatible oil on the rubber OD prior to installation prevents the elastomer from tearing against the housing chamfer during the press-fit operation.