SJ-2B4601TK (Mitsubishi Electric)

SJ-2B4601TK is a Mitsubishi Electric SJ-B series built-in AC spindle motor, used in medium-duty CNC machining centers. It belongs to the SJ-2B spindle motor family, and is one of the higher-power variants in the 4500/4600 class range.

🔧 Verified specifications (official Mitsubishi data)

From Mitsubishi SJ-B series specification manual:

Parameter	Value
Continuous rated output	22 kW
Short-time rated output	26 kW (30 min rating)
Acceleration/deceleration output	26 kW (standard)
Actual accel/decel output	31.2 kW
Base speed	1250 rpm (low-speed coil) / 3000 rpm (high-speed coil)
Maximum speed	10,000 rpm
Continuous torque	168 N·m / 70 N·m (coil dependent)
Short-time torque	199 N·m / 82.8 N·m
Rotor inertia	0.105 kg·m²
Frame class	160–230 mm spindle body
Stator OD	Φ254.5 mm class
Cooling	Liquid / oil jacket cooling
Drive unit	MDS-D2-SP-320

🔧 Model code breakdown

Code part	Meaning
SJ	Mitsubishi spindle motor family
2B	SJ-B built-in spindle series
4601	22 kW class winding / configuration
TK	terminal / connector type

So:

SJ-2B4601TK = 22 kW built-in spindle motor for medium-to-heavy CNC machining

⚙️ Where it fits in the SJ-2B lineup

Compared with similar models:

Model	Power class	Character
SJ-2B4501TK	7.5 kW	medium duty
SJ-2B6602TK	11 kW	high torque
SJ-2B4601TK	22 kW (high class)	heavy-duty machining

So 4601TK is a significantly higher-power spindle, used in larger machines.

🏭 Typical applications

SJ-2B4601TK is used in:

large vertical machining centers (VMCs)
heavy milling machines
steel and cast iron cutting
boring / drilling operations
industrial production CNC systems

It is selected when machines require:

🧱 high cutting power (22 kW class)
⚖️ strong low-speed torque
🎯 stable continuous machining under load
🔧 heavy-duty industrial reliability

⚖️ Position in Mitsubishi spindle lineup

Series	Role
SJ-2B	compact built-in spindle motors (older generation)
SJ-BG	modern high-speed integrated spindles
SJ-DG	high-torque cutting spindles
SJ-DL	external high-speed spindle motors

🧠 Simple explanation

SJ-2B4601TK is a 22 kW built-in CNC spindle motor designed for heavy-duty machining centers, offering high torque, strong cutting capability, and stable industrial performance.

Mitsubishi M80 Built-IN Spindle Motor SJ-2B4601TK

Description