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Straight Pipe Thread Plug Gages

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Straight Pipe Thread Plug Gages

  • Straight pipe working plug gages are used to check the size of the internal threads of a part
  • Straight pipe setting plug gages calibrate and set a straight pipe thread ring
  • Setting plug gages inspect the ring gage for wear
  • 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



Size Member Item # Price
1/8-27 GO / NOGOSPWP-01Call
DOUBLE ENDSPWPDE-01Call
1/4-18 GO / NOGOSPWP-02Call
DOUBLE ENDSPWPDE-02Call
3/8-18 GO / NOGOSPWP-03Call
DOUBLE ENDSPWPDE-03Call
1/2-14 GO / NOGOSPWP-04Call
DOUBLE ENDSPWPDE-04Call
3/4-14 GO / NOGOSPWP-05Call
DOUBLE ENDSPWPDE-05Call
1-11 1/2 GO / NOGOSPWP-06Call
DOUBLE ENDSPWPDE-06Call
1 1/4-11 1/2 GO / NOGOSPWP-07Call
DOUBLE ENDSPWPDE-07Call
1 1/2-11 1/2 GO / NOGOSPWP-08Call
DOUBLE ENDSPWPDE-08Call
2-11 1/2 GO / NOGOSPWP-09Call
DOUBLE ENDSPWPDE-09Call
2 1/2-8 GO / NOGOSPWP-10Call
DOUBLE ENDSPWPDE-10Call
3-8 GO / NOGOSPWP-11Call
DOUBLE ENDSPWPDE-11Call


Straight pipe plug working plug gage is used to check the size of internal threads to ensure the threads are within its designed tolerance limits. Straight pipe setting plug gages are designed for two functions; to calibrate and set a straight pipe thread ring gage, and to inspect the ring gage for wear. Straight thread pipe plug gages consist of two (2) members (GO and NO GO) and follow the same gaging principles as the working thread plug gages; the part being checked is generally acceptable when the NO GO member does not enter more than 1 1/2 to 3 turns dependent upon customer specifications.

NPS straight pipe working thread plugs, straight pipe set plugs and straight pipe thread ring gages are manufactured per ANSI/ASME B1.20 specifications. Straight pipe thread gages are supplied in Class 2A for rings and set plugs and 2B for working thread plug gages. WESTport gages are manufactured to the highest end of the ANSI specifications to ensure the longest gage life possible. 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

WESTport Manufactured Products. 24th Anniversary Servicing Industry Worldwide (1989-2013)