How to Improve Tool Life in Turning

Issuing time:2024-04-05 14:47

The three main machining parameters when turning are speed, feed and depth of cut. Each factor affects tool life. To achieve the best turning tool life:


Reduce cutting speed v c (to reduce heat)


Optimize feed f n (minimize cutting time)


Optimize cutting depth a p (reduce the number of cuts)


Cutting speed, v c

Too low

  • Built-in edge


    Blunted edge


    Uneconomical


    Poor surface

Too high

  • Rapid wear of the back cutting edge


    Poor finish


    Rapid crater wear


    Plastic deformation

Cutting speed vc has a great influence on tool life. Adjust vc to obtain the best economic vc. (Tool life on the Y axis

Feed rate, f n

Too light

  • Longitudinal beam


    Fast wear of the back cutting edge


    Built-in edge


    Uneconomical

Too heavy

  • Less chip control


    Poor surface finish


    Cradle wear/plastic deformation


    High power consumption


    Chip welding


    Chip hammering

Depth of cut, p

Too small

  • Less chip control


    Vibration


    Overheating


    Uneconomical

Too deep

  • High power consumption


    Breakage of blades


    Increased cutting forces

Tool maintenance

Establishing a tool maintenance routine in your shop will increase turning tool life, prevent problems and save money.

Check the insert seat

It is important to ensure that the insert seat is not damaged during machining or handling.


Look for:


Pockets that are too large due to wear. Inserts not properly seated on both sides of the slot. Check clearance using a 0.02 mm (0.0008 in) gauge


No gaps allowed in the corners between the shim and the bottom of the pocket


Shim damage. Shims should not have chipped corners in the cutting area


Shim wear due to chip breaking and/or insert indentation


Cleaning the blade seat

Make sure the insert seat is free of dust or chips from machining. If necessary, clean the insert seat with compressed air. If a boring bar with a cutting head is used, it is also important to check and clean the connection between the cutting head and the boring bar when the cutting head is changed.

Torque wrench

For optimal performance of screw-clamp toolholders, the insert should be properly tightened using a torque wrench. Use the recommended torque for each toolholder.


Too much torque can negatively affect the performance of the tool and cause the insert and screw to break


Too little torque can cause the insert to move, vibrate and reduce cutting results


Clamping screw

 Always use a torque wrench to ensure that the screws are properly tightened. Use adequate screw lubrication to prevent the screws from seizing. Lubricant should be applied to the screw threads and screw head surfaces. Replace worn or damaged screws.