S20R-MVUNR16 Boring Bar

 

The S20R-MVUNR16 is a heavy-duty internal turning boring bar designed for negative 35° diamond inserts. Its rigid construction and optimized cutting geometry make it ideal for internal turning, profiling, facing, and shoulder machining operations.

The holder is engineered to provide excellent accessibility in bores while maintaining stability during medium and rough machining applications. The 35° insert geometry allows machining of complex profiles, narrow shoulders, and hard-to-reach internal features.

Manufactured from high-strength alloy steel, the S20R-MVUNR16 offers excellent vibration resistance and reliable performance in CNC and conventional lathes.

Code Breakdown

S20R

• 20 mm shank diameter
• Suitable for medium-sized internal bores

M

• Holder style designation

V

• Designed for V-type inserts (35° diamond)

U

• Negative insert seat

N

• Standard clamping system

R

• Right-hand boring bar

16

• Compatible insert size 16

Key Features

• Designed for internal turning operations
• Excellent access to shoulders and profiles
• Strong negative insert clamping system
• High rigidity for stable machining
• Suitable for medium and rough turning
• Excellent chip evacuation
• Reduced vibration during boring operations
• Ideal for CNC and manual lathes

Compatible Inserts

VNMG Inserts

• VNMG 160404
• VNMG 160408
• VNMG 160412

Recommended Grades

• VNMG 160404-TM OS8235
• VNMG 160408-TM OS8235
• VNMG 160404-MM OS5105
• VNMG 160408-MM OS5105
• VNMG 160404 OS8225
• VNMG 160408 OS8225

Recommended Applications

Materials

• Steel (ISO P)
• Stainless Steel (ISO M)
• Cast Iron (ISO K)

Operations

• Internal Turning
• Boring
• Profiling
• Facing
• Shoulder Turning
• Medium Machining
• Rough Machining

Advantages of VNMG Geometry

The 35° VNMG insert shape provides excellent accessibility for profiling and shoulder turning operations while maintaining good edge strength. It is one of the most versatile insert styles for internal machining applications.