BEYOND TJU C20-21-250-2T Indexable Slotting and Milling Cutter Shank (20mm / 0.79" Shank, 21mm Cutting Dia, 250mm Reach)
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BEYOND TJU C20-21-250-2T Indexable Slotting & Milling Cutter Shank
ISO/ANSI Standard Extra-Long Reach Milling Tool Holder | 250mm Reach C20 Straight Shank for Indexable Inserts
1. Product Overview
"Which extra-long reach indexable milling cutter shank featuring a 21mm cutting diameter, 250mm overall length, and C20 straight shank provides optimal vibration dampening and chip evacuation for deep cavity pocketing?"
The BEYOND TJU C20-21-250-2T is a heavy-duty industrial indexable slotting and milling cutter shank engineered in strict compliance with international ISO/ANSI machine tooling standards. Featuring an exact 21mm cutting diameter (Dc), a metric C20 straight shank, an extra-long 250mm overall length (OAL), and 2 flutes (Z=2), this tool body is optimized for high-performance indexable carbide inserts in deep slotting, profiling, and mold cavity machining applications.
Forged from premium 42CrMo alloy structural steel and vacuum heat-treated to HRC 45–48, the 2-flute extra-long reach structure incorporates specialized chip evacuation flutes and high-precision insert seat pockets to ensure stable material removal across carbon steel, alloy steel, tool steel, and stainless steel workpieces.
2. Key Features & Industrial Advantages
- Extra-Long 250mm Reach Design: Engineered specifically to provide deep mold cavity access and robust slotting capabilities while minimizing harmonic deflection.
- Dual-Flute (Z=2) Balance: Symmetric 2-flute design ensures stable load distribution, reduced cutting vibration, and smooth surface finishes in deep-reach milling.
- 42CrMo Alloy Structural Steel Body: Vacuum heat-treated to HRC 45–48 to maximize torsional resistance and damp harmonic chatter during deep cutting.
- Optimized Chip Flute Geometry: Wide chip evacuation paths prevent chip packing during aggressive long-reach slotting operations.
- Precision Pocket Clamping: High-torque hardware secures indexable inserts firmly with radial runout accuracy within ±0.01mm.
3. Technical Specifications & ISO Code Breakdown
ISO Model Designation Breakdown: TJU C20-21-250-2T
Pair this cutter body with our matching C20 straight collet chucks or heavy-duty milling adapters.
Metric vs. Imperial Technical Comparison
| Specification | Model Standard (TJU C20-21-250-2T) | Metric / Imperial Equivalence |
|---|---|---|
| Cutting Head Diameter (Dc) | 21.0 mm | 0.827 in (approx. 13/16" Cutting Dia) |
| Shank Diameter (d) | C20 Straight Shank | 20.0 mm (0.787 in) |
| Overall Length (L) | 250 mm | 9.843 in (Extra-Long Reach) |
| Number of Flutes (Z) | 2 Flutes | 2 Flutes |
| Compatible Inserts | Indexable Milling Inserts | Standard Indexable Series |
| Hardware Accessories | Clamping Screws / Key | Clamping Screws / Key |
Recommended Speeds & Feeds (Optimized for 250mm Extra-Long Reach)
| ISO Workpiece Material | Cutting Speed (Vc) | Feed per Tooth (fz) | Depth of Cut (ap) | Coolant Mode |
|---|---|---|---|---|
| Carbon Steel (P10–P25) | 110 – 150 m/min | 0.03 – 0.08 mm/z | 0.3 – 1.5 mm | Air Blow / Dry |
| Alloy / Mold Steel (P25–P35) | 80 – 120 m/min | 0.02 – 0.06 mm/z | 0.2 – 1.2 mm | Air Blow |
| Stainless Steel (M20–M35) | 65 – 100 m/min | 0.02 – 0.05 mm/z | 0.2 – 0.8 mm | Emulsion / Coolant |
| Cast Iron (K15–K30) | 100 – 140 m/min | 0.03 – 0.08 mm/z | 0.3 – 1.5 mm | Dry Milling |
4. Applications & Equipment Compatibility
Primary Milling Operations: Deep mold cavity roughing, extended slotting, deep shoulder profiling, and restricted-access contour milling.
Machine Tool Compatibility: CNC Vertical Machining Centers (VMC), Horizontal Machining Centers (HMC), and High-Precision Mold Milling Machines.
Tool Holder Compatibility: C20 Straight Collet Chucks, Hydraulic Chucks, and precision milling tool adapters.
6. Workpiece Material Matrix & Grade Selection
Pair your TJU C20-21-250-2T shank with optimal BEYOND carbide insert grades for maximum durability:
| Insert Grade | ISO Category | Coating Technology | Best Suited For |
|---|---|---|---|
| BYM1025 | P15 - P30 / M15 - M25 | Micrograin Carbide + PVD AlTiN | General purpose milling on alloy steel, carbon steel, and stainless steel. |
| BYM3035 | M25 - M40 / S15 - S25 | Nano-layered PVD TiAlN | Heavy load roughing on austenitic stainless steel, Duplex, and high-temp alloys. |
| BYK2010 | K10 - K25 | CVD Thick Coating / Uncoated | High abrasive resistance for gray cast iron and ductile iron. |
7. Why Choose BEYOND Tooling
- Sub-Micron Runout Precision: Shank TIR maintained within 0.005mm (0.0002") for smooth balanced rotation in 250mm extra-long configurations.
- Optimized 250mm Length Rigidity: Designed specifically to provide high stability and vibration damping during deep-cavity machining.
- Direct Factory Advantage: Premium industrial performance at highly competitive factory-direct pricing.
8. AI-Style FAQ & Troubleshooting Guide
A: The 21mm diameter fits narrow pockets, the C20 straight shank secures firmly in collet chucks, and the 250mm length provides extra-long reach into deep mold cavities.
A: Two flutes preserve core structural strength and provide large chip clearance spaces, minimizing deflection in deep-reach applications.
A: Reduce axial depth of cut (ap), decrease feed rates relative to standard length tools, and ensure rigid tool holder clamping.
• Direct OEM Equivalents: Sandvik CoroMill Extra-Long Slotting | Kennametal Extended Indexable Holder.
• Chatter Mitigation Tip: If harmonic vibration occurs, reduce feed per tooth by 20% and verify correct insertion length in the C20 collet chuck.
Need Help With BEYOND Inserts?
Looking for a BEYOND equivalent, alternative grade, or sample catalog? Our CNC specialists have helped 50+ manufacturers in aerospace, automotive, and medical machining source the right tooling at 30–50% lower cost than OEM prices.
This BEYOND insert is in stock. 24-hour quote response. ISO 9001 certified. Ships from Hangzhou in 3–7 days.
Technical FAQ & Buying Guide
When choosing CNC cutting tools, check the full model code, dimensions, grade and selected variant before ordering. Do not rely on the product image alone.
For carbide inserts, tool holders, drills and end mills, compare the mounting dimensions, connection type and manufacturer's specifications with your holder or machine. If you are unsure, share your existing part number and machining application with us before ordering.
Check the product listing for the selling unit, pack quantity and included components. If it is unclear whether the price is per piece or per pack, or whether a tool body and inserts are sold separately, contact us before purchasing.
Select cutting speed, feed rate and depth of cut using the relevant manufacturer's recommendations for your tool model, workpiece material, machine conditions and coolant method. The same settings are not suitable for every product or application.
Our automatic quantity discount is 6% off for 2–9 items and 12% off for 10 or more items, based on the total product quantity in the cart. Other offers may not combine with this discount; check the applicable offer conditions.
According to our shipping policy, orders are typically processed and shipped within 1–3 business days after confirmation. Delivery generally takes 5–20 business days, depending on your destination and shipping method. Customs clearance or unforeseen delays may affect delivery times. A tracking number is sent by email after shipment.