HONING ALLOWANCES

Minimum stock allowance for removal of surface imperfections.
Finished ID
Inch
0.065
and
Under
Over
0.065
to
0.125
Over
0.125
to
0.180
Over
0.180
to
0.230
Over
0.230
to
0.360
Over
0.360
to
0.460
Over
0.460
to
0.563
Up to 1.500
0.010
0.011
0.013
0.015
Over 1.500 to 3.000
0.010
0.012
0.014
0.016
0.018
Over 3.000 to 4.000
0.011
0.013
0.015
0.017
0.019
0.021
0.023
Over 4.000 to 4.750
0.014
0.016
0.018
0.020
0.022
0.024
Over 4.750 to 6.000
0.015
0.017
0.019
0.021
0.023
0.025
Over 6.000 to 8.000
0.016
0.018
0.020
0.022
0.024
0.026
Over 8.000 to 10.500
0.022
0.023
0.025
0.027
Over 10.500 to 12.500
0.023
0.024
0.026
0.028
Over 12.500 to 14.000
0.024
0.025
0.027
0.029
Over 14.000 to 15.000
0.025
0.026
0.028
0.030

NOTE: These allowances plus nominal size tolerances must be considered in calculating the size to be ordered.


HONING


Example #1: Establish ID size of 5″ OD tube which will clean up by honing to a 4.238/4.240″ ID.
Step 1
5.000” OD – 4.238” (minimum finished ID) = .762÷ 2” = .381 nominial wall. Minimum clean up allowance for removal of ID surface imperfections from table 2 is .023”
Step 2
Minimum honed size
4.238”
 
Less
-.023
clean up allowance from table #2
 
Maximum ID size to order
=4.215”
Step 3
Standard drawn-over mandrel ID tolerance for this size is:
[one_fourth_last]+.000”[/one_fourth_last]
-0.14″
 
Therefore ordered ID size should be 4.215”

Example #2: Establish ID size of 8.500” OD tube which will clean up by honing to 7.664/7.666” ID.

Step 1
8.500” OD – 7.664” (minimum finished ID) = .836÷ 2” = .418 nominal wall. Minimum clean up allowance for removal of ID surface imperfections from table 2 is .025”
Step 2
Minimum honed size
7.664”
Less .025
clean up allowance from table #2
= 7.639″
Step 3
7.639″
 
Less the + ID tolerance
-.025”
 
Maximum ID size to order
=7.614″
Step 4
Standard ID tolerance for this size is
+.025″
–.025″
 Therefore ordered ID size will be 7.614″
+.025″
-.025″