φ620mm Swing · φ220mm Max Grinding · One-clamp bore & face grinding

The MK2120 is a CNC turret internal grinding machine designed for efficient and high-accuracy inner bore finishing on medium to large-diameter components. Capable of handling holes from 20mm to 220mm in diameter and grinding up to 200mm in depth, this model is ideal for machining deep, precise bores with minimal setup time.

MK2120 Series

Regular maintenance

Spare parts supply

On-site installation service

Customized design

Key Features

● Wide Internal Grinding Range: 20–220mm. Accommodates both small precision holes and large industrial bores.

● Deep Bore Grinding: Up to 200mm. Allows for machining of long bushings, deep sleeves, and internal cylinders.

● Turret Tool System: Supports automatic switching between grinding heads or dressing tools to reduce downtime.

● CNC-Controlled Axes: Enables full automation of feed, positioning, and spark-out cycles for superior repeatability.

● High Rigidity + Thermal Stability: Ensures long-term dimensional accuracy under continuous production conditions.

Get More Details →

Recommended Configurations

● Workpiece Spindle & Clamping: Servo/variable frequency motor, pneumatic/hydraulic fixtures, centers or centerless support, optional cooling

● Feeding & Motion System: Servo motor, ball screw, precision rails, gap compensation

● Wheel Dressing System: Internal wheel dresser (single-point/roller/diamond), automatic cycle setting

● Cooling & Chip Removal: Cooling circulation, adjustable nozzles, filtration (magnetic separator + paper filter), chip conveyor

● Control & Automation: HMI touch screen, automatic loading/unloading

● Measurement & Compensation: Contact/laser probe, rotary encoder/displacement sensor

● Safety & Protection: Enclosed cover, interlock system, emergency stop, wheel protection, spark/dust protection

● Accessories & Options: Workpiece positioning stand, internal fixture, lighting, non-standard fixtures

Get More Details →

Application Case

● Client: Automotive Gear Manufacturer (Czech Republic).

● Workpiece: Gear bores with 180mm ID, 150mm deep.

● Setup: MK2120 with dual turret heads, coolant tank, and Siemens CNC.

● Results: Achieved bore tolerance: IT5 level (≤±0.005mm), cycle time reduced by 28% with turret switching, bore roundness deviation: < 2μm, surface finish: Ra 0.4 μm.Client feedback: “Exceptional deep bore performance with reduced operator effort.”

Get More Details →

Specifications	Unit	MK2120
Grinding hole diameter	mm	20-220
Max.grinding depth	mm	200
Max.swinging over the table	mm	620
Max.table travel(Z-axis)	mm	600
Max.travel of the wheel head(X-axis)	mm	200
Max.speed of Z-axis	m/min	8
Max.speed of X-axis	m/min	5
Workpiece spindle speed	r/min	100～500
Bore roundness	mm	0.002
Cylindricity of bore	mm	0.004
Surface roughness of bore	μm	Ra0.32
Surface roughness of end face	μm	Ra0.63
Perpendicularity of end face to bore	μm	0.005
Max.turning angle of headstock	°	30
Total power of machine	kw	18
Machine weight	kg	4500

MN CATALOG.pdf

Frequently Asked Questions

1、I only have part drawings. Can you recommend a suitable internal cylindrical grinding machine?

Absolutely! Minnuo has an experienced pre-sales technical team. As long as you provide the part drawings, whether it's for internal hole machining with an internal cylindrical grinding machine or a customized model with combined functions, we can recommend a single machine within 10 minutes. For solutions involving multiple machines, a complete proposal will be provided within 5 working days.

2、Can I customize a CNC internal cylindrical grinding machine to match my process requirements?

Yes. I can customize a CNC internal cylindrical grinding machine based on workpiece size, accuracy requirements, automation level, and more—including spindle type, grinding wheel configuration, automatic loading/unloading system, and cooling system—so it fully matches my on-site production needs.

3、 How is the quality of your internal cylindrical grinding machines guaranteed?

We are equipped with multiple high-end international machining centers, ensuring that all key components of the internal cylindrical grinding machine have high precision and consistency. Each machine is fully tested before delivery and comes with a detailed quality inspection report.

4、What is the typical delivery time?

For standard models, we have inventory available for fast delivery. For customized internal cylindrical grinding machines, the delivery time is generally 30–45 working days. We will confirm the exact timeline based on the complexity of the order.

5、Do you support full machine customization?

Yes. Whether it’s the control system, machine bed design, grinding range, or sheet metal guarding, I can fully customize the internal cylindrical grinding machine based on my specific needs. You also offer combined solutions like internal and external cylindrical grinding machines in a single setup.

6、What types of workpieces are suitable for an internal bore grinding machine?

An internal bore grinding machine is mainly used for machining internal holes of parts such as sleeves, gear bores, bearing inner rings, and hydraulic components. You can use it to achieve high-precision grinding of inner bores, stepped holes, tapered holes, and more. It is widely applied in industries like automotive, hydraulics, and mold manufacturing.

7、What level of accuracy can a high precision internal grinding machine achieve?

Our high precision internal grinding machine can consistently achieve machining accuracy within 2μm, and some high-end models can reach below 1μm in a temperature-controlled workshop. If I have high requirements for roundness or coaxiality, I can also choose optional in-process measuring systems and active dressing units.

8、Is it complicated to maintain an internal cylindrical grinding machine during use?

Not at all. You only need to regularly check the lubrication oil, grinding wheel wear, spindle operation status, and whether the cooling system is functioning properly. Our internal cylindrical grinding machine is designed with a compact structure and easy maintenance in mind. We also provide maintenance manuals and training services to help you complete daily upkeep with ease.