Programming instructions

ADT-CNC4620 Programming Manual
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22. What are the influences of cutting amount on cutting temperature?
A: If cutting speed increases by one time, the cutting temperature increases about 30%-40%; if the
feeding amount increases by one time, the cutting temperature only increases 15%-20%; if the
cutting depth increases by one time, the cutting temperature only increases 5%-8%.
23. What is process dimension chain?
A: The connected dimensions are arranged into closed dimension drawing, which is the dimension
chain; the dimension chain applied in the processing is called process dimension chain.
24. What is positioning error?
A: The position error of the processing surface relative to process reference due to workpiece
positioning is called positioning error.
25. What are the errors may be generated in the processing?
A: The errors in the processing might be principle, clamp installation, machine tool, clamp
precision, process system distortion, worepiece residual stress, tool and measurement.
26. What is the objective of using clamp in machinery manufacture?
A: In machinery manufacturing, the objective of using clamp is to ensure product quality, improve
labor productivity, solve the special difficulty in lathe processing, expand the processing range of
the machine tool, and reduce the technical requirement on workers.
27. What spindles are used if the workpiece is positioned with internal hole?
A: Commonly used spindles include cylindrical, small taper, cone, thread, and splined spindles.
28. What are the effects of positioning device and clamping device?
A: The effect of the positioning device is to confirm the position of the workpiece in the clamp,
making the workpiece in the proper position relative to tool and cutting motion during processing.
The effect of the clamp device is to clamp the workpiece, ensuring that the given position of the
workpiece in the clamp won’t change during processing.
29. What is repeat positioning? What is partial positioning?
A: The positioning points are more than the degrees of freedom that should be limited, indicating
that certain positioning points limit same degree of freedom, which is called repeat positioning.
30. What are machine tool errors? What are their main influences on the quality of workpiece?
A: Machine tool errors include:
1) The error between machine tool principal axis and bearing due to manufacture and wear;
It has bad influences on roundness, flatness and surface roughness of the workpiece.
2) The error due to machine tool rail wear, which will causse error in the straightness of
cylinder.
3) Machine tool transmission error: it destroies proper motion relationship and cause pitch
error.
4) Machine tool installation position error, e.g. parallel error of guide rail and principal axis
installation, which will cause taper error in processed cylinder.
31. What are geometric accuracy and work precision of the lathe?