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Carmex Carbide Threading Insert - NPT - TiAlN Coated - 21-14NPT
| Application | Threading |
| Thread Form | NPT |
| Internal or External | Internal & External |
| Insert Size | 21 |
| Pitch | 14 |
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The Carmex Carbide Threading Insert – NPT, TiAlN Coated, model 21-14NPT is a versatile cutting solution built for machinists who routinely produce pipe-thread profiles. With robust carbide and a TiAlN coating, it delivers reliable performance across common NPT and related thread jobs.
- Thread profiles covered: A single insert family designed to address all common threading profiles you encounter in pipe fittings and hydraulic components.
- Five length options: Available in five lengths spanning 12 mm to 40 mm to fit a variety of recess depths and tooling setups.
- Pitch range: Depending on length, capable of handling pitches from 0.5 mm (32 TPI) up to 6.0 mm (4 TPI).
- Double-edged design (where applicable): Most profiles use two cutting edges for extended life; note that BSPT, NPT, NPTF, American Buttress, and API RD variants are exceptions to the double-edged rule.
- Internal/external threading compatibility: For many thread profiles, the same insert can machine both internal and external threads, reducing tool changes (with some profile exceptions such as ISO / UN / NPSM / UNJ / Acme).
- TiAlN coating: Titanium aluminum nitride coating provides enhanced hardness and heat resistance for longer tool life and consistent thread quality.
- Carbide construction: Premium carbide body delivers precise, stable cuts and long-term durability in demanding threading operations.
This insert is ideal for machine shops and production environments where a single tool family must cover a wide range of NPT and related thread applications—from hydraulic fittings to pneumatic connectors. The TiAlN coating helps maintain sharpness under heat, while the various lengths and pitch options let you tailor each cut to the specific job. Use with compatible holders and appropriate coolant strategies to maximize life and achieve smooth, accurate thread finishes on both internal and external threads where supported.
| Application | Threading |
| Thread Form | NPT |
| Internal or External | Internal & External |
| Insert Size | 21 |
| Pitch | 14 |
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: Carmex Carbide Threading Inserts - NPT - TiAlN Coated
View full collection →You are viewing 21-14NPT. Click any other SKU to view its full details.
| Product SKU | Insert Size | Pitch | Price | Stock | Order |
|---|---|---|---|---|---|
| 12-18NPT | 12 | 18 | £29.10 | In Stock | |
| 14-14NPT | 14 | 14 | £29.10 | In Stock | |
| 14-18NPT | 14 | 18 | £29.10 | In Stock | |
| 21-11.5NPT | 21 | 11.5 | £38.88 | In Stock | |
| 21-14NPT Viewing | 21 | 14 | £38.88 | In Stock | |
| 30-11.5NPT | 30 | 11.5 | £53.38 | In Stock | |
| 30-8NPT | 30 | 8 | £53.38 | In Stock | |
| 40-11.5NPT | 40 | 11.5 | £91.88 | 5 days | |
| 40-8NPT | 40 | 8 | £91.88 | 5 days |
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