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OSG Threading Tap - NPT Spiral Point HSS-E - Steam Oxide Coated - Through Hole - 3/8 x 18
| Form | NPT |
| Size | 3/8 |
| Pitch | 18 |
| Flute Length | 1.1/16 |
| Shank Diameter | 5.542 |
| Overall Length | 3.3/16 |
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The OSG NPT Spiral Point Threading Tap is built for through-hole tapping of 3/8-18 NPT threads, delivering fast, precise results for plumbing, hydraulic, and pneumatic components. With a robust HSS‑E cobalt core and a Steam Oxide finish, it stands up to repeated use in challenging materials while maintaining accurate threads.
- Size / Thread: 3/8-18 NPT through-hole threading tap designed for efficient, reliable pipe-thread production.
- Material: HSS‑E (high-speed steel with cobalt) for enhanced hardness and heat resistance during demanding tapping tasks.
- Coating: Steam Oxide coating to improve wear resistance and lubricity, extending tool life in production environments.
- Geometry: Spiral point design promotes immediate chip evacuation, reducing face and flank rubbing in through-holes.
- Through-Hole Suitability: Specifically optimized for through-hole tapping to yield clean, consistent threads in a single pass.
- Precision & Durability: OSG engineering delivers tight tolerances and long tool life for reliable, repeatable results.
This tap is ideal for manufacturers and shop floors that demand durable performance in through-hole NPT threading. The combination of HSS‑E cobalt and Steam Oxide coating reduces wear under high cutting temperatures, helping maintain thread accuracy across batches. The spiral point geometry accelerates chip clearance, minimizing tool chatter and downtime, so you can complete more parts with fewer tool changes. Whether outfitting hydraulic manifolds, pneumatic fittings, or pipe assemblies, this tap provides dependable, repeatable threads that meet standard NPT specifications.
| Form | NPT |
| Size | 3/8 |
| Pitch | 18 |
| Flute Length | 1.1/16 |
| Shank Diameter | 5.542 |
| Overall Length | 3.3/16 |
| Substrate | HSS-E |
| Style | Spiral Point |
What time are Protool open?
We are open Monday to Friday between 8:30am and 5pm.
Do you offer Free Next Day delivery?
Yes! We offer Free Next Day delivery via Royal Mail Tracked 24 on all orders over £50 ex VAT*. We also offer Free DPD Local Next Day delivery on all orders over £100 ex VAT*.
We also offer the following:
- Royal Mail Tracked 24 — £5.90 (FREE on orders over £50 ex VAT*). Order before 4:30pm for next day delivery. No signature required.
- DPD Local Next Day — £8.00 (FREE on orders over £100 ex VAT*). Standard next day delivery to UK mainland addresses.
- Royal Mail Special Delivery — £12.50. Guaranteed delivery before 1pm the next working day.
- DPD Saturday Delivery — £25.00. Must be ordered on Friday before 4pm. Pre-12pm delivery.
For delivery to Scottish Highlands & Islands, Northern Ireland, Republic of Ireland, or overseas locations, additional charges apply. Please see our delivery page for full details, or call us on 01732 887 334.
*T's & C's and exclusions apply. Please see our delivery page for more information on all our services.
Full Range: OSG Threading Taps - NPT Spiral Point HSS-E - Steam Oxide Coated - Through Hole
View full collection →You are viewing OSG-22628784. Click any other SKU to view its full details.
| Product SKU | Size | Pitch | Flute Length | Shank Diameter | Overall Length | Price | Stock | Order |
|---|---|---|---|---|---|---|---|---|
| OSG-22628764 | 1/8 | 27 | 0.75 | 0.318 | 2.1/8 | £69.52 | In Stock | |
| OSG-22628774 | 1/4 | 18 | 1.1/16 | 0.429 | 2.7/16 | £95.62 | In Stock | |
| OSG-22628784 Viewing | 3/8 | 18 | 1.1/16 | 5.542 | 3.3/16 | £112.98 | In Stock | |
| OSG-22628794 | 1/2 | 14 | 1.3/8 | 0.687 | 3.1/8 | £139.05 | In Stock | |
| OSG-22628804 | 3/4 | 14 | 1.3/8 | 0.906 | 3.1/4 | £201.63 | 1-2 days | |
| OSG-22628814 | 1 | 11.5 | 1.3/4 | 1.125 | 3.3/4 | £272.89 | 1-2 days |
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