DIN Standards Committee Technical Fundamentals
Geometrical product specifications (GPS) - Gauges for ISO metric screw threads - Dirt grooves
Geometrische Produktspezifikation (GPS) - Lehren für Metrisches ISO-Gewinde - Schmutznuten
This standard specifies the design of dirt grooves on gauges for ISO metric screw threads. There are cases where usual cleaning of the threads under test is insufficient. When screwing in the thread gauge ("GO" plug gauge or "GO" screw ring gauge), a dirt groove will accommodate residual thread contaminations still remaining in the thread and prevents them from becoming trapped between the work piece and the thread gauge. "NOT GO" plug gauges and "NOT GO" screw ring gauges are not provided with dirt grooves, since these are not required here. This standard has been prepared by Subcommittee NA 152-03-02-07 UA "Längenprüftechnik außer Koordinaten-, Form- und Oberflächenmesstechnik sowie Gewindekenngrößen" ("Length checking practice except coordinate, form and surface measuring technology as well as characteristics of screw threads") of the Standards Committee Technical Fundamentals (NATG) at DIN.