Piston rings up to 200 mm diameter for reciprocating internal combustion engines. Designs, dimensions and designations for single piece rings. Keystone and half keystone compression rings. Specification for keystone rings

This specification outlines the technical requirements for trapezoidal section piston rings designed for reciprocating internal combustion engines featuring piston diameters of 200 millimeters or less. It specifically addresses the design principles, dimensional tolerances, and nomenclature used for rings with trapezoidal cross-sections within the broader series dedicated to engine components. The document establishes the necessary parameters to ensure interoperability and performance consistency during manufacturing and assembly processes. Detailed guidelines are provided for the geometric configuration of the ring profile, which is critical for maintaining effective sealing properties and minimizing friction within the cylinder bore. Furthermore, it defines the standard classification and identification methods required for these components, facilitating clear communication between suppliers and engine manufacturers. The content focuses solely on the structural and dimensional attributes, serving as a reference for technical planning and quality control without encompassing testing procedures or operational performance assessments.