Page 1049 - Tungaloy Catalog

Technical Reference
Drilling Tools
Nomenclature for gun reamer

Guide pad Driver
Tip Shank

Corner Oil hole
Margin
Primany
clearance angle Secondary clearance angle
Secondary engage angle
Primary engage angle

Troubleshooting in gun reaming

Trouble Possible Causes Countermeasures
• Enlarge chamfer angle and
• Chamfer angle small
Increased burnishing torque increase stock allowance
due to excessively small stock • Reduce cutting speed to prevent
allowance • Excessive wear in peripheral peripheral wear of edge
cutting edge • Increase lubricity of cutting fluid
Breaking of reamer
• Faulty filtering of cutting fluid • Improve flitering accuracy
Sticking • Incorrect selection of cutting • Change to fluid with higher lubricity
fluid
• Insufficent cutting fluid pressure • Increase fluide pressure
• Repair electrical system
Mechanical trouble
• Improve clamping method of workpiece
• Reduce fluid pressure
Excessive feed rate per tooth
• Increase number of teeth
• Excessive chamfer angle • Reduce chamfer angle
Unacceptable Improper tool specifications • Excessive back taper • Reduce back taper
• Peripheral run out excessive • Improve run out accuracy
surface • Cutting edge run out is large • Improve run out accuracy
roughness Faulty regrinding
• Residual damage of preceding process • Remove residual damage completely
• Excessive fluid pressure
• Reduce fluid pressure
Too large and Improper cutting fluid • Improper selection of cutting • Increase activity and lubricity of the fluid
Faulty machining accuracy Faulyt machine accurancy • Clamping position wrong • Correct spindle run out and Technical Reference
inconsistant over
fluid
size
bushing clearance and alignment
• Improper clamping position
Faulty clamping of workpiece
• Clamping force inadequate
• Increase clamping force
• Excessive bushing clearance
• Correct bushing clearance
• Correct peripheral run out
• Outer run out of reamer large
Improper tool specifications
Defective Faulty machine accuracy • Faulty spindle run out and alignment • Correct spindle run out and alignment 14
• Insufficient reamer rigidity • Increase reamer rigidity
out of roundness
Faulty clamping position of workpiece • Chamge clamping position
• Reduce reamer guide width
Unevenness in wall thickness of workpiece
(margin width)
Chamfer angle small • Increase chamfer angle
Insufficient
Excessive wear in peripheral • Cutting speed • Decrease cutting speed
oversize
cutting edge • Faulty lubricity of cutting fluid • Increase lubricating capacity
allowance
Faulty regrinding (residual damage) • Increase regrinding stock amount
14–31