The joint ring K 66165 is a precision sealing component developed for use with locking screw K 66164 in the charge air cooler housing system of the Sulzer ZV40/48 engine. Positioned between the locking screw and the housing surface, its main function is to provide effective sealing against air leakage, pressure loss, and contamination ingress during engine operation. Engineered to withstand thermal variation, vibration, pressure loading, and environmental influences, the joint ring is manufactured from high-quality sealing materials optimized for long-term durability and operational reliability. Accurate dimensional tolerances ensure even compression and dependable sealing performance throughout repeated maintenance and operational cycles. By preserving pressure integrity and supporting stable fastening conditions, the K 66165 joint ring contributes to efficient operation of the charge air cooler system, reliable turbocharging performance, and reduced maintenance requirements in demanding diesel engine applications.