Straight pipe thread ring gages are adjustable and used to measure threads on an outside diameter (OD) to ensure the threads are within its designed tolerance limits. The straight pipe thread ring gage is a one piece construction with a single setting adjustment feature, manufactured to an X tolerance and American Gage Design standards (AGD).

Straight pipe thread ring gages are root relieved for longer life and more accurate gaging. The ring gages are manufactured with a root clearance in the major diameter which eliminates the possibility of interference from the full form section of the thread setting plug and major diameter of the part being gaged. This feature assures that the thread flanks are making proper contact.

Straight pipe thread gages are supplied in Class 2A for rings and set plugs and 2B for working thread plug gages. Manufactured to Class 2A, GO or NOGO members. Straight thread ring gages class and tolerances conform to ASME/ANSI B1. Thread inserts are made of oil hardening graphitic tool steel, manufactured to the highest end of the ANSI specifications, ring lapped and hand polished to ensure maximum wearability. Straight pipe plug gages are available in NPSM, NPSC, NPSL, NPSF and NPSI (Description and applications below)

Straight thread pipe gage descriptions and applications:

• NPSM - National Pipe Straight Mechanical External and internal threads are intended for free-fitting mechanical joints where there are no internal pressures. Part is gaged with straight pipe GO and NOGO plug gages and straight pipe GO and NOGO ring gages.
• NPSL - National Pipe Straight Locknut External and internal threads are intended to produce a thread having the largest diameter that is possible to cut on standard pipe. Part is gaged with straight pipe GO and NOGO plug gages and straight pipe GO and NOGO ring gages.
• NPSC - National Pipe Straight Coupling Internal threads are intended to form low pressure tight joints when assembled with NPT external threads by using a sealer. Part may be gaged with a NPT plug gage or with straight pipe GO and NOGO plug gages.
• NPSF- Dryseal American Standard Fuel - Internal threads are intended for use in soft or ductile materials for assembly with NPTF external threads without using a sealer. Part may be gaged with an NPTF-L1 basic notch plug gage or with straight pipe GO or NOGO plug gages
• NPSI - Dryseal American Standard Intermediate - Internal threads are intended for use in hard or brittle materials for assembly with PTF-SAE short external threads but may also be assembled with full length NPTF external threads. Part may be gaged with an NPTF-L1 basic notch plug gage or with straight pipe GO or NOGO plug gages.

• Straight pipe thread ring gages are used to measure threads on an outside diameter
• Root relieved for longer life and more accurate gaging
• Manufactured to X tolerance and American Gage Design standard
• Class 2A, GO or NOGO members
• Precision hand lapped to provide optimum finish and superior accuracy
• Manufactured to the highest end of the ANSI specifications to provide maximum wearability
• Final inspection of gages is completed in an environmentally controlled ISO 17025 laboratory
• Available in NPSM, NPSC, NPSL, NPSF and NPSI
• Free NIST certificate of accuracy