External Turning Tool Holder B&W-Clamp



  • Manufactured from High Tensile Steel to provide better yield strength under heavy working conditions.
  • Used for various external cutting operations on the lathe.
  • The clamp holds the negative type insert rigidly in place for stability during operations.
  • The inserts can be easily and rapidly replaced once worn down thus saving machining time and cost.
  • Rust preventive black oxide finish.
  • Inserts can be provided on request.
External Turning Tool Holder B&W-Clamp
External Turning Tool Holder B&W-Clamp

Application

External turning tool holders are used for material removal from the outer surface of the workpiece through operations like longitudinal turning, facing or a combination of both in order to obtain the required length, diametre and contour.

  • Turning: The operation in which the tool moves along the axis of the workpiece in order to reduce its diametre to the required size.
  • Facing: The operation in which the tool moves into the workpiece or in a direction perpendicular to the axis of the workpiece.

The turning tool holders are available in a number of shapes and sizes each having their distinguish entering/lead angle, seat inclination angle and clamp styles. 

Nomenclature

Cutting Geometry

 

  • Entering Angle: The angle between the cutting edge and the direction of the feed.
  • Lead Angle: The angle made by the plane of the workpiece with the cutting edge of the tool.
  • End Cutting Edge Angle: The angle between the end cutting edge and the feed direction.
  • Insert Rake Angle: The angle between the cutting edge when viewed from the side and the axis of the insert’s seat.
  • Inclination Angle: The angle of the axis of the insert’s seat with respect to the horizontal axis.
  • Effective Rake Angle: Combination of the Insert rake angle and the inclination angle, formed between the cutting edge and the horizontal axis.
  • Clearance Angle / Side Relief: The inclination of the insert with respect to the vertical axis.

Effects of cutting geometry

Nose Radius

The angle formed between the main and the auxiliary cutting edge of the insert is called the nose radius. The larger the angle, higher is the cutting edge strength of the insert. Thus a higher nose radius is preffered for roughing operations. However, large nose radius also gives rise to higher distribution of cutting forces, both axially and radially, therefore increasing the power consumption as well as the vibration tendencies. Inserts with smaller nose angles are prefered for finishing, profiling or for turning intricate contours inaccessible to larger radii.

 

Holder shapes

Different holders are available for different entering angles and insert clearances. 

Rigid and lever clamping methods facilitate mounting of negative inserts (N) or inserts with 0° clearance angle, whereas screw clamping methods facilitates the clamping of N type inserts as well as inserts with some positive clearance angle.

Positive inserts consume lower power for material removal and exert lower forces. As the clearance angle increases, the strength of the cutting edge decreases. Negative inserts on the other hand provides higher edge strength but consume more power and exert higher cutting forces.

Type Size

Dimension

(mm)

Carbide Insert

Action

H L
APPROACH ANGLE 93°

BTJNR/L

2020 K16 20 125

TNXX 1604XX

2525 M16 25 150
3232 P16 32 170
APPROACH ANGLE 105°

BTQNR/L

2020 K16 20 125

TNXX 1604XX

2525 M16 25 150
3232 P16 32 170
APPROACH ANGLE 60°

BTENN

2020 K16 20 125

TNXX 1604XX

2525 M16 25 150

3232 P16 32 170

APPROACH ANGLE 95°

BCLNR/L

2020 K15 20 125

CNMX 1504XX

2525 M15 25 150
3232 P15 32 170
APPROACH ANGLE 93°

BDJNR

2020 K15 20 125

DNXX 1504XX

2525 M15 25 150
3232 P15 32 170
APPROACH ANGLE 62.5°

BDNNN

2020 K15 20 125

DNXX 1504XX

​​

2525 M15 25 150
3232 P15 32 170
APPROACH ANGLE 95°

BWLNR/L

 

 

2020 K06 20 125

WNXX 0604XX

2525 M06 25 150
2020 K08 20 125

WNXX 0804XX

2525 M08 25 150
APPROACH ANGLE 93°

BVJNR/L

2020 K16 20 125

VNXX 1604XX

2525 M16 25 150
3232 P16 32 170
APPROACH ANGLE 117.5°

BVQNR/L

2020 K16 20 125

VNXX 1604XX

2525 M16 25 150
3232 P16 32 170
APPROACH ANGLE 72.5°

BVVNNN

2020 K16 20 125

VNXX 1604XX

2525 M16 25 150
3232 P16 32 170
APPROACH ANGLE 93°

WTJNR/L

 

 

2020 K16 20 125

TNXX 1604XX

2525 M16 25 150
3232 P16 32 170
2525 M22 25 150

TNXX 2204XX​

APPROACH ANGLE 60°

WTENN

 

 

2020 K16 20 125

TNXX 1604XX

2525 M16 25 150
3232 P16 32 170
2525 M22 25 150

TNXX 2204XX​

APPROACH ANGLE 105°

WTQNR/L

 

 

2020 K16 20 125

TNXX 1604XX

2525 M16 25 150
3232 P16 32 170
2525 M22 25 150

TNXX 2204XX​