Page 22 - Heat_Exchanger_2020
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Drilling Tool Wear
Heat Exchangers
Edge Chipping Land Wear
Cause Cause
• Low wear resistance carbide grade • Cutting speed too high
• Built-up edge has been formed • Low wear resistance carbide grade
• Insufficient coolant fluid • Radial run-out is too high
Remedy Remedy
• Reduce feed rate • Check that the correct geometry is used
• Increase cutting speed • Check that T.I.R run-out does not exceed 0.02 mm
• Increase coolant pressure • Reduce cutting speed
• Improve jet direction in case of external coolant supply • Increase coolant pressure
• Change to different geometry • Improve jet direction in case of external coolant supply
• Check tool and part clamping rigidity • Check and improve tool and part clamping rigidity
• Check if pocket gripping forces are too
low - if so, replace the tool body
Corner Fracture Corner Chipping
Cause Cause
Caused by excessive insert wear • Radial run-out is too high
before indexing the insert • Insufficient coolant fluid
• The grade and geometry could be Remedy
too weak for the applications • Check radial run-out
• Excessive load on the insert • Reduce feed rate increase the speed
• Built-up edge has been formed on the insert • Check tool and part clamping rigidity
Remedy • Check if pocket gripping forces are too
• Check radial run-out low - if so, replace the holder
• Reduce feed rate • Increase coolant pressure
• Increase the speed • Improve jet direction in case of external coolant supply
• Check tool and part clamping rigidity
• Check if pocket gripping forces are
too low, replace the holder
• Increase coolant pressure
• Improve jet direction in case of external coolant supply
Chisel Chipping Built-up Edge
Cause Cause
• Chisel run-out is too big • Cutting zone temperature is too low
• Combine of high feed and low speed • Negative cutting geometry
Remedy • Machining of very sticky materials such as low-
• Reduce feed rate and increase the cutting speed carbon steel, stainless steels, and aluminum
• Check that chisel misalignment Remedy
does not exceed 0.02 mm • Increase the feed
• Check tool and part clamping rigidity • Increase cutting speed
• Check if pocket gripping forces are too • Increase coolant pressure
low - if so, replace the holder • Check oil percentage in the coolant fluid
22 ISCAR
