Description
SJ-DL3.7/240-01T is a Mitsubishi Electric SJ-DL series low-inertia CNC spindle motor designed for ultra-high-speed drilling and tapping machines, optimized for very fast acceleration and extremely high RPM operation.
This is the highest-speed variant in the SJ-DL 3.7 kW class (240 frame).
📊 Verified specifications
| Parameter | Value |
|---|---|
| Series | SJ-DL (Low inertia spindle motor) |
| Rated continuous output | 1.5 kW |
| Short-time rated output | 3.7 kW (10 min rating) |
| Acceleration/deceleration output | 15.0 kW (standard) |
| Actual accel/decel output | 18.0 kW |
| Base speed | 3000 rpm |
| Maximum speed | 24,000 rpm |
| Frame type | C71 (240-class frame) |
| Shaft diameter | Ø22 mm |
| Flange size | 130 mm square |
| Flange fitting diameter | Ø110 mm |
| Total length | 375 mm |
| Mass | 17 kg |
| Cooling | Machine-integrated (no fan) |
| Protection | IP54 (shaft excluded) |
(Source: Mitsubishi SJ-DL spindle motor specification tables)
⚙️ What “240” means
- /240 = ultra-high speed spindle configuration
- Higher RPM capability than /150 or /100 variants
- Designed for:
- very fast tapping cycles
- micro drilling
- precision high-speed machining
From Mitsubishi’s SJ-DL lineup:
- DL series is dedicated to drilling & tapping machines requiring very fast response
⚙️ What “T” means
T = Through-spindle / hollow-shaft configuration
Used for:
- through-tool coolant
- high-speed tapping spindles
- compact spindle cartridge integration
🧠 How this motor behaves
This is NOT a heavy cutting motor.
It is designed for:
- ⚡ extremely fast acceleration
- 🔁 frequent start/stop cycles
- 🎯 tapping and drilling precision
- 📈 very high RPM (up to 24,000)
But it has:
- ❌ low cutting torque
- ❌ not suitable for rough milling
⚖️ Position in Mitsubishi spindle hierarchy
| Series | Purpose |
|---|---|
| SJ-D | Balanced general spindle |
| SJ-DJ | Compact/lightweight spindle |
| SJ-DG | High torque + dynamic cutting |
| SJ-DL | Ultra high-speed tapping / drilling |
🧠 Simple explanation
SJ-DL3.7/240-01T is a 24,000 RPM ultra-high-speed CNC spindle motor designed for drilling and tapping machines, optimized for speed and response rather than cutting power.