Evaluating a Pre-Owned MURATEC MW120G CNC Twin Spindle Turning Center

When you’re buying a used Muratec MW120G, you’re not just purchasing a machine—you’re buying a high-speed production system designed for automation. This model is widely used in automotive and high-volume manufacturing thanks to its twin spindle + gantry loading architecture.

Below is a professional, expert-level evaluation checklist tailored specifically for this machine type.

1. Understand the Machine Architecture First

Before inspection, align expectations with how this machine works:

• Twin spindle (left + right) → simultaneous machining or part transfer
• Dual turret (8–12 tools each) → parallel operations
• Gantry loader → fully automated loading/unloading
• Short cycle production machine (as low as ~16 sec cycles)

This is not a job-shop lathe. It is a mass production cell machine.

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2. Core Technical Specifications (Benchmark Reference)

Use these as your baseline during evaluation:

Parameter	Typical MW120G Value
Chuck Size	6″–8″ (Ø165–210 mm)
Spindles	2
Max RPM	up to 6,000 rpm
Spindle Power	~11 kW × 2
Turrets	2 (8–12 tools each)
Turning Diameter	~120–295 mm range
Turning Length	~120–145 mm
Loader Capacity	~3 kg parts (dual)

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3. Mechanical Inspection (Critical for MW120G)

A. Spindle Condition (MOST CRITICAL)

• Check both spindles independently:
  • Bearing noise at high RPM
  • Thermal growth / vibration
  • Runout (micron-level expected)

Twin spindle misalignment = scrap production risk

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B. Turret & Tooling System

• Indexing accuracy (no backlash)
• Tool clamp rigidity
• Hydraulic turret locking condition

Weak turret = poor surface finish

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C. Gantry Loader System

This is where most used machines fail.

Check:

• Rail wear (especially carbon rail versions)
• Pick/place repeatability
• Cycle time consistency
• Sensors & gripper wear

If gantry fails → machine becomes useless for automation

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D. Slideways & Axes

• X/Z axis backlash
• Ball screw wear
• Servo load readings

Typical travels:

• X ≈ 130 mm
• Z ≈ 145 mm

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4. CNC & Electrical System

Most machines come with:

• Fanuc control (16T / 18i / 31i variants)

Check:

• Alarm history
• Servo load graphs
• Ladder modifications (automation lines often customized)

Important: Many MW120G machines were part of production lines, not standalone units.

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5. Automation & Integration Check

Ask the seller:

• Was this part of a transfer line or standalone cell?
• Is PLC / gantry logic complete?
• Are original programs included?

Missing automation logic = expensive rebuild

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6. Production History (Hidden Truth)

This machine is designed for:

• Automotive components
• High-volume repetitive parts
• Continuous operation (24/7)

Typical claim:

• Failure rate can be extremely low in production setups

But…

Used machines often have:

• Millions of cycles
• Heavy wear on loader + spindle

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7. Accuracy & Test Cut

Always request:

• Test cut on both spindles
• Roundness measurement
• Surface finish comparison

Why critical?

Twin spindle machines must:

• Match parts between operations
• Maintain micron-level tolerance

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8. Common Risk Areas (MW120G Specific)

High Risk

• Gantry loader failure
• Spindle mismatch (left vs right)
• Missing automation software

Medium Risk

• Hydraulic turret wear
• Chip evacuation system

Lower Risk

• Fanuc control (generally reliable)

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9. Ideal Buyer Profile

This machine is PERFECT if you:

• Run high-volume production
• Need cycle time reduction
• Want lights-out manufacturing

Not ideal if:

• Low batch / job shop work
• Frequent setup changes

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10. Professional Buying Decision Formula

Before purchasing, confirm:

✔ Mechanical integrity (spindles + turret)
✔ Automation system fully functional
✔ Control + PLC complete
✔ Test cut proven
✔ Spare parts availability

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Final Expert Insight

The MURATEC MW120G CNC Twin Spindle Turning Center is not just a CNC lathe—it’s a production system.

If you buy a good one → extremely profitable machine
If you buy a worn-out one → expensive automation problem

Muratec “Murata” MW120G CNC Twin Spindle Turning Center

With Overhead Gantry Loader, Fanuc 31iTB CNC Control, MW-200G (Left) & MW-120G (Right) Pallet Stocker Feeder Tables, All Installed Chucks, Tool Holders & Options Included

Specification	Metric	Imperial
Distance Between Spindles	340 mm	13.39 in
Max. Swing	295 mm	11.61 in
Standard Chuck Size	152 / 203 mm	6 / 8 in
Turning Diameter (Nominal)	120 mm	4.72 in
Turning Diameter (Max)	240 mm	9.44 in
Turning Length (Nominal)	80 mm	3.15 in
Turning Length (Max)	100 mm	3.94 in
Number of Turret Stations	8
X-Axis Stroke	130 mm	5.12 in
X-Axis Traverse Rate	24 m/min	945 IPM
Z-Axis Stroke	145 mm	5.71 in
Z-Axis Traverse Rate	24 m/min	945 IPM
Rapid Traverse Rate (X & Z)	24 m/min	78.78 FPM
Spindle Speed Range	45 – 4500 RPM	45 – 4500 RPM
Spindle Nose	A2-5
Spindle Bore	47 mm	1.850 in
Spindle Motor Power	11 kW	15 HP
Tool Shank Size (Square)	19 mm	0.75 in
Tool Shank Size (Round)	40 mm	1.570 in
Machine Weight (Approx.)	5,350 kg	11,800 lbs
Floor Space (L x W)	3540 x 3460 mm	139.37 x 136.22 in

Loader Specifications

Specification	Metric	Imperial
X-Axis Stroke (Left / Right)	200 / 1600 mm	7.87 / 63 in
X-Axis Max Speed	150 m/min	492 FPM
Y-Axis Stroke	485 mm	19.09 in
Y-Axis Max Speed	110 m/min	361 FPM
Z-Axis Stroke	155 mm	6.10 in
Z-Axis Max Speed	35 m/min	115 FPM
A-Axis Rotation	180°
A-Axis Speed	0.6 sec / 180°
Gripper Outer Diameter	90 mm	3.54 in
Gripper Jaw Stroke	30 mm	1.18 in
Max Workpiece Weight	3.6 kg x 2	8 lb x 2

Equipped With

• Fanuc 31iTB CNC Control
• Overhead Gantry Loader
• Rear Chip Conveyor
• (14) Pallet Stocker Feeder Tables (Left: MW-200G / Right: MW-120G)
• Coolant Tank and Pumps
• All Books & Manuals
• All Installed Chucks & Tool Holders