NPTF, ANPT
NPTF Threads are also known as Dryseal threads as they do not require a sealant to form a leak-proof joint.
| Type | Standard | Plug gauges | Ring gauges |
|---|---|---|---|
| NPFT | ANSI/ASME B 1.20.5 | Thread plug gauges L1 & L3 (Basic Step or Min/Max Step) 6 Step Crest Check Plug |
Thread ring gauges L1 & L2 (Basic Step or Min/Max Step) 6 Step Crest Check ring |
| ANPT | SAE SA71051B | Thread plug gauges L1 & L3 (Basic Step or Min/Max Step) 6 Step Crest Check Plug |
Thread ring gauges L1 & L2 (Basic Step or Min/Max Step) 6 Step Crest Check ring |
- NPTF & ANPT threads require additional gauging as the truncation of these threads should be maintained within specified limits.
- L1 & L3 plug gauges and L1 & L2 Ring gauges are used in combination to verify the size and taper of the component threads along the thread length.
- 6 Step Crest check plug and ring gauges are used to verify the crest diameter and truncation of the component threads along the thread length.