- 98% satisfied customers
- 72h delivery
- 30 dni na zwrot
Description
DIAMETER Ø21.5 mm
MORSE TAPER MT2
OVERALL LENGTH 248 mm
FLUTE LENGTH 150 mm
Technical specifications of the Ø21.5 mm drill bit
Twist drill with Morse taper shank
| TECHNICAL DATA | |
|---|---|
| Diameter | Ø21.5 NWKc HSSE |
| Standard | DIN 345 |
| Drill type | NWKc — twist drill with taper shank |
| Material | HSSE (cobalt high-speed steel) |
| Overall length l1 | 248 mm |
| Flute length l2 | 150 mm |
| Morse taper | MT2 |
| Point angle | 118° |
| Diameter tolerance | h8 |
| Cutting direction | Right-hand |
Ø21.5 mm HSSE twist drill – MT2 Morse taper
Product description and key benefits
The Ø21.5 mm twist drill with an MT2 Morse taper is designed for drilling mounting holes and through holes in structural steel up to 140 mm thick. The MT2 taper with a diameter of 17.780 mm ensures stable torque transmission at drilling diameters from 14 to 23 mm. The Ø21.5 Morse taper drill mounts directly in the spindles of shop-grade pillar drilling machines.
Key benefits of the Ø21.5 mm metal drill bit
- 5% cobalt in the HSS matrix — raises the tempering temperature to 650°C — 50°C higher than standard HSS
- Direct mounting in an MT2 spindle — eliminates the chuck as a source of runout — particularly important when drilling stainless steels, where runout reduces surface quality
- Drilling austenitic steels — the HSSE cutting edge handles work hardening in 304/316/321 steels
- h8 diameter tolerance — repeatable hole size even in difficult-to-machine materials
- Conforms to DIN 345 — dimensions identical to HSS — a replacement for use in existing machining cells
- Repeated resharpening — HSSE steel retains its properties after the cutting edge is reground on a tool grinder
The Ø21.5 Morse taper drill is designed for drilling holes in steel components of various thicknesses — from thin sheet metal to thick-walled sections. The versatile diameter allows one tool to be used for multiple operations at a single workstation. H12 tolerance holes, Ø21.500–Ø21.710 mm; close fits require reaming.
Morse tapers – dimensions to DIN 228
Dimension table for all Morse tapers MT0–MT6
| Taper | Diameter D [mm] | Length [mm] |
|---|---|---|
| MT0 | 9.045 | 49.8 |
| MT1 | 12.065 | 53.5 |
| MT2 | 17.780 | 64.0 |
| MT3 | 23.825 | 80.5 |
| MT4 | 31.267 | 117.5 |
| MT5 | 44.399 | 149.5 |
| MT6 | 63.348 | 210.0 |
REDUCTION SLEEVES COMPATIBLE WITH THE Ø21.5 MM DRILL BIT:
| ✓ | MT2 → MT3 — for a spindle with an MT3 socket |
| ✓ | MT2 → MT4 — for a spindle with an MT4 socket |
| ✓ | MT2 drill drift — for removing the drill bit from the spindle |
Cutting data for the Ø21.5 mm drill bit according to ISO 513
Recommended machining conditions for a diameter of Ø21.5 mm
| ISO symbol | Workpiece material | Vc [m/min] | f [mm/rev] | n [rpm] | Vf [mm/min] |
|---|---|---|---|---|---|
| P Steel | Structural steel up to 900 N/mm² | 11÷20 | 0.20 | 163÷296 | 33÷59 |
| K Cast iron | Gray cast iron GG20–GG30 | 13÷16 | 0.20 | 192÷237 | 38÷47 |
| N Copper and Al alloys | Cu, CuZn, Al, and alloys | 25÷28 | 0.25÷0.32 | 370÷415 | 92÷133 |
Deep-hole drilling (over 3×D)
When drilling holes deeper than 64 mm (3×Ø21.5), periodically retract the drill every 1–1.5×D to remove chips. Use ample emulsion cooling (minimum concentration of 6–8%). Reduce the feed by 30–50% from nominal values.
Material compatibility of the Ø21.5 mm drill bit
Range of workpiece materials and application limitations
✓ Structural steel (S235, S355) up to 900 N/mm²
✓ Gray and ductile cast iron (GG20, GGG40)
✓ Low-carbon and medium-alloy steel
▲ Stainless steel (Vc reduced by 30%, ample coolant)
▲ Aluminum and Al alloys (emulsion coolant required)
✗ Hardened steels above 45 HRC
Frequently asked questions about the Ø21.5 mm drill bit
In S235/S355 structural steels, spot drilling is not necessary — the 118° angle provides self-centering. Spotting with a 90° NC spotting drill is recommended when drilling on uneven or inclined surfaces, where the drill may slip away from the marked point.
The HSS drill can be used for stainless steel with Vc reduced by 40% and ample cooling with a 8–10% emulsion. An HSSE (cobalt) drill of the same diameter is a more efficient option, retaining its hardness up to 650°C.
A pillar or box-column drilling machine with an MT2 spindle and a minimum power rating of 0.75–1.5 kW. Bench drilling machines with a drill chuck are not recommended — they cannot transmit the torque generated at a diameter of 21.5 mm.
Product accessories
Long reduction sleeve MK1-2 PTPb 1762
Reference: 0000006908 In stock > 10 items
€15.79
€19.42 brutto
Reduction sleeve MK4 MK2 1751 PTPa DIN 228
Reference: 1181 In stock > 10 items
€15.79
€19.42 brutto
Reduction sleeve MK5 MK2 1751 PTPa DIN 228
Reference: 4910 In stock > 10 items
€22.37
€27.51 brutto
Reviews
No customer reviews for the moment.
Shipping
All orders are delivered by courier company GLS. For orders exceeding 369 PLN gross shipping is FREE
| Courier GLS | Przelew24 / Prepayment | 14,76 zł gross | Delivery time 1 working day |
| Courier GLS | Cash on delivery | 17,26 zł gross | Lead time 1 working day |
Recommended for you
This website uses its own and third-party cookies to improve our services and show you advertising related to your preferences by analyzing your browsing habits. To give your consent to its use, press the Accept button.
Cookie preferences
Functional cookiesTechnical
Functional cookies are strictly necessary to provide the services of the shop, as well as for its proper functioning, so it is not possible to refuse their use. They allow the user to browse through our website and use the different options or services that exist on it.
Advertising Cookies
These are cookies that collect information about the advertisements shown to users of the website. They can be anonymous, if they only collect information about the advertising spaces shown without identifying the user, or personalised, if they collect personal information about the user of the shop by a third party, for the personalisation of these advertising spaces.
Analytics cookies
Collect information about the user's browsing experience in the shop, usually anonymously, although sometimes they also allow the user to be uniquely and unequivocally identified in order to obtain reports on the user's interests in the products or services offered by the shop.