Pipe Thread Gages
Designed to perform under pressure...
Different geometry for different applications...
L1 Pipe Gages
The L1 when screwed onto the pipe or plug
into the hole "hand tight" should be flush with the end of the pipe or the hole, or gage plane, within 1 turn.
L2 & L3 Pipe Gages
After using the L-1 gage the L2 ring or L3 plug is assembled with the part and must stop within 1/2 turn plus or minus of where the L1 stopped.
6 Step Pipe Gages
The NPTF & ANPT system begins with the use of the L-1 gage having a 1 turn in or out limit (2 turns total) the same as the NPT system.
