Starving Artist Law

Surface texture and lead angle are critical parameters for the proper functioning of dynamic sealing systems. These parameters directly affect the fluid interface between security seals and shaft, impacting seal integrity. Out-of-spec parts have the potential to fail prematurely in the field, costing the transportation industry millions of dollars per year in fines, recalls, and in-warranty failures. Traditionally, shaft and seal manufacturers qualify their parts using a defined combination of stylus and string measurement methods to meet the zero-degree lead specified in ISO Standard 6194 and RMA 1999-1-1, 2004 specification. The string method in particular has proven to be qualitative rather than quantitative, and lacks sensitivity to detect micro lead and lead angles near 0 degrees. In addition, reliable results depend heavily upon part alignment and operator experience. Responding to the transportation and related industries’ needs for a more precise and reliable methodology, a comprehensive and repeatable measurement system that assures confidence in production quality.