- 美国GSG美标管螺纹量规
- 美国GSG石油螺纹规│GSG牙形板
- 美国GSG美标ASME螺纹规
- 美国GSG精密量规│进口量仪
- 美国GSG螺纹指示规│螺纹量仪
- 美国GSG倒角量规│锪孔量规
- 瑞士Trimos测高仪│Trimos测长机
- Hexagon影像仪│海克斯康三坐标
- 苏州Mitutoyo日本三丰量具
- Fischer菲希尔涂层测厚仪
- Elcometer易高涂层测厚仪
- GE超声波探伤仪
- 奥林巴斯超声波探伤仪
- GBIS超声波探头
- Bruker布鲁克光谱仪
- 赛普斯SCIAPS光谱仪
- Western Instrument仪器
- G.A.L. Gage焊接量规
- Clark硬度计│Sun-Tec
- 日本future-tech硬度计
- King便携式布氏硬度计
- Rex Gauge邵氏硬度计
- Ames便携式洛氏硬度计
- Hemco Gage螺纹规
- PMC Lone Star石油量规
- Vermont螺纹规│VTG螺纹规
- GageAssembly螺纹规
- Threadmaster进口螺纹规
- WESTport Corporation
- Threadcheck螺纹规│三线规
- Mueller Gage沟槽量仪
- Kroeplin精密卡规
- 美国环球Universal Punch
- 德国Schwenk进口内径量仪
- Allen Gauge and Tool
- Fowler High Precision
- Swiss Precision Instruments
- Flexbar Machine Corporation
- Acem螺纹规│Stub Acme螺纹规
- 苏州工量具│测量仪器
- Wrentham Tool Group
- Meyer Gage针规、梅尔量规
- ASKER橡胶硬度计
- NAKANISHI高速主轴
- OJIYAS螺纹规│OJIYAS气动量仪
- Microset 复制胶
- DeFelsko涂层测厚仪
- OSG丝锥│OSG螺纹规
- Western Gage 气动量仪检具
- Michigan Spline Gage Co
- Southwest Calibration Service
- McCord and Company
- Pennoyer-Dodge Company
- Pi Tape Texas, LLC
- BARCOR INC.
- Advanced Systems and Designs
- Calmetrics Inc
NPT Taper Plug and Ring Gauges
Gauges for testing threads to American National Standard ANSI/ASME B.1.20.1 - 1983.
This standard covers dimensions and gauging of pipe threads for general purpose applications.
The main types of threads designated are NPT, NPSC and NPSM.
The significance of each letter is as follows:
N = National (American) Standard
P = Pipe
T = Taper
C = Coupling
S = Straight
M = Mechanical
NPT Threads
Threaded fittings made to this standard consist of an external taper and an internal taper to form a joint having general purpose applications. These threads are intended to be made up wrench-tight, with a sealant whenever a pressure-tight joint is required.
The taper of the thread is 1:16 on diameter, normal to the axis. The pipe fittings range in size from 1/16 inch to 24 inch.
Provision is made for two types of gauge.
Master gauges: used to check working gauges.
Working gauges: used to check product threads during and after manufacture.
A set of master gauges
consists of a taper plug with a gauging notch located at L1 distance from the small end. The ring gauge has an overall length equal to the L1 dimension. This ring is fitted to its mating plug seating flush at the gauging notch. It should be understood that only a specifically matched set of masters (L1 plug and L1 ring) can be expected to assemble together within a stand-off tolerance of +/-0.002 inch as specified.
A set of working gauges
consists of a taper plug gauge having a basic step at L1 distance from the small end, and a taper ring having an overall length equal to the L1 dimension. Plug and ring gauges can be supplied with limit steps to indicate the minimum and maximum diametral condition of the product. These gauges are known as MIN/MAX. The basic steps can be included or omitted as requested.
The L1 dimension is the axial distance from the small end of the pipe to the plane of handtight engagement.
These are parallel internal threads only in pipe couplings, and have the same thread form as the NPT thread. They are used to form pressure tight joints when assembled with NPT external threads, and made up wrench-tight with a sealant.NPSC Threads
The threads range in size from 1/8 inch to 4 inch.
Go/No Go parallel plug gauges can be supplied to test the diametral limits of these threads, although the standard states that NPT taper plug gauges should be used to test the internal product thread where the mating external threads are tapered and a pressure tight joint is required.
NPSM Threads
These are parallel threads, internal and external. The basic thread details correspond with NPT threads at the plane of handtight engagement.
Free fitting mechanical joints are used for special applications where there are no internal pressures. NPSM threads range in size from 1.8 inch to 6 inch.
- Notation
- H = 0.866025p = height of 60deg. sharp V thread
- h = 0.800000p = height of thread on product
- p = 1/n = pitch (measured parallel to axis)
- n = number of threads per inch
- a = 30deg. = thread flank angle
- ß = 1deg. 47 min. = thread taper angle for 1/16 taper
- fc = depth of truncation at crest
- fr = depth of truncation at root
- Fc = width of flat at crest
- Fr = width of flat at root