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Carmex Carbide Threading Insert - NPT - TiAlN Coated - 40-8NPT
| Application | Threading |
| Thread Form | NPT |
| Internal or External | Internal & External |
| Insert Size | 40 |
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The Carmex Carbide Threading Insert for NPT and common thread profiles is a TiAlN-coated solution built for machinists who need reliable, high-precision threading across internal and external surfaces.
- Five length options: Inserts are available in five lengths, ranging from 12 mm to 40 mm, to fit a variety of hole depths and turning passes.
- Broad thread compatibility: Covers all common thread profiles, reducing the need to stock multiple tool types.
- Pitch range flexibility: Capable of handling pitches from 0.5 mm (32 TPI) to 6.0 mm (4 TPI) for diverse applications.
- Double-sided cutting edges: Each insert features two cutting edges to maximize usable life, with exceptions for BSPT / NPT / NPTF / American Buttress / API RD.
- Internal & external threading: For many profiles, the same insert can machine both internal and external threads, minimizing tool changes (except ISO / UN / NPSM / UNJ / Acme).
- NPT-focused design: Specifically optimized for NPT and related pipe-thread profiles, supporting accurate, consistent taps on threaded parts.
- 40-8NPT designation: Clear sizing and compatibility for standard NPT threading tasks.
This carbide threading insert set is engineered to deliver durable performance in demanding materials and high-speed threading. The TiAlN coating enhances hardness and wear resistance, helping maintain accuracy over longer runs and reducing tool downtime. With its versatile length and pitch options, it’s well-suited for job shops, contract manufacturers, and in-house production environments that require reliable threading across multiple standards without swapping inserts mid-operation.
Part Numbers
- Protool Part Number
- 40-8NPT
- Brand
- Carmex
- Category
- Thread Mill
Delivery
Free UK mainland delivery on orders over £50 ex VAT. In-stock items ordered before 4:30pm are dispatched the same working day. Full delivery information.
Returns
14-day returns on unused stock items in original packaging. Special-order and bespoke tooling is non-returnable. Read our returns policy.
Technical Support
Over 30 years of machining experience behind the counter. Call 01732 887334, Mon–Thurs 8:30–17:30, Fri 8:30–16:30.
Trade Accounts
Credit accounts, contract pricing and scheduled call-off orders available for trade customers. Apply for an account.
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 40-8NPT. Click any other SKU to view its full details.
| Product SKU | Insert Size | Pitch | Price | Stock | Order |
|---|---|---|---|---|---|
| 12-18NPT | 12 | 18 | £32.74 | In Stock | |
| 14-14NPT | 14 | 14 | £32.74 | In Stock | |
| 14-18NPT | 14 | 18 | £32.74 | In Stock | |
| 21-11.5NPT | 21 | 11.5 | £43.74 | In Stock | |
| 21-14NPT | 21 | 14 | £43.74 | In Stock | |
| 30-11.5NPT | 30 | 11.5 | £60.05 | In Stock | |
| 30-8NPT | 30 | 8 | £60.05 | In Stock | |
| 40-11.5NPT | 40 | 11.5 | £103.37 | 5 days | |
| 40-8NPT Viewing | 40 | 8 | £103.37 | 5 days |
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