System 21 requirements even though you did not use Go/NoGo gaging. For example if you are inspecting a nut per System 21 and you have the Go/NoGo work plug, but you don’t have the Go/NoGo minor diameter plug. If you have an ID mic, you can use the ID mic to qualify the minor diameter to System 21. Let’s get into the particulars now, and

A thread that passes using System 22 automatically qualifies the product to meet System 21 requirements even without the use of a go/no-go. In addition to system 21 and 22 gauging, it is common to also measure the basic thread geometry such as major, pitch and minor diameter with the use of thread wires, micrometers and optical comparators.

Gaging Systems Part 2: System 22 Last issue, we covered System 21 Gaging Systems, and this time we are going to go a little deeper and cover System 22 requirements. I just wanted to recap on the definition of a gaging system according to the standards. ASME B1.3 – 2007, Section 1 defines a gaging system as: a list of screw thread

The simplest acceptable thread inspection system, as defined by the American Society of Mechanical En-gineers (ASME) in the thread acceptability standard ASME B1.3, is System 21. The requirements of a Sys-tem 21 Inspection are the evaluation of the limits or size of the following thread characteristics: External Threads • GO Maximum Material

(ASME) Bl. 3M, System 21 unless the product print specifi- cally requires other inspection requirements. System 21 re- quires the thread to be inspected for maximum-material (GO), minimum-material (NOT GO or HI) and minor diameter. These three characteristics can be inspected with either fixed limit

Gaging Systems Part 2: System 22 Read More >> Adjustable Thread Ring Gage Calibration Procedure Read More >> Standard’s Appendixes Hold Valuable Information Read More >>

in accordance with Gaging System 21 as specified in American Society Of Mechanical Engineers, ASME BI.3M. ASME 131.1 Section 1.7: ACCEPTABILITY Acceptability Of product threads shall be in accordance with ASME Bl .3M. Gages and gagtng shall be in accordance with ASME 01.2. ASME Bl .2 Section 4: TYPES OF GAGES FOR PRODUCT INTERNAL THREAD 4.

tion. These systems are designated as Systems 21, 22 & 23. System 21 is the most basic system and the one required for the inspection Of threads on most commercial fasteners. System 22 is required for the inspection Of threads on many automotive fasteners and most aerospace fasteners. Sys- tem 23 is use in research and development projects and

characteristic measuring requirements of ANSI/ASME Systems 21, 22, and 23 and MIL-S-7742 and MIL-S-8879 "Other" and "Safety Critical" inspection levels. These easy-to-use gages provide accurate, repeatable, and re-producible measurements. They can all be changed from size to size in less than 3 minutes. Electronic digital readouts are standard,

requirements of ANSIIASME 81.3M, system 21. This measurement is required when inspecting to System 22 "VARIMINOR" Fingers These fingers are for measuring the Minor Diameter on internal threads or the inside diameter of parts with holes in them. This measurement is a requirement of ALL thread measuring standards and systems.