Machinery's Handbook, 31st Edition
1318 CYLINDRICAL GRINDING Variables of the cylindrical grinding process, often referred to as grinding data, com prise the speed of work rotation (measured as the surface speed of the work); the infeed (in inches per pass for traverse grinding, or in inches per minute for plunge grinding); and, in the case of traverse grinding, the speed of the reciprocating table movement (expressed either in feet per minute, or as a fraction of the wheel width for each revolution of the work). For the purpose of starting values in setting up a cylindrical grinding process, a brief listing of basic data for common cylindrical grinding conditions and involving frequently used materials, is presented in Table 3. Table 3. Basic Process Data for Cylindrical Grinding Traverse Grinding Traverse for
Each Work Revolution, In Fractions of the Wheel Width Rough Finish
Infeed per Pass
Work Surface Speed,
inch
mm
Work Material
Material Condition
fpm m/min Rough
Finish
Rough Finish
Annealed 100 30.5 0.002 0.0005
0.05
0.013
1 ∕ 6 1 ∕ 8 1 ∕ 6 1 ∕ 8 1 ∕ 6 1 ∕ 8
1 ∕ 2
Plain Carbon Steel
Hardened 70 21 0.002 0.0003–0.0005 0.05 0.007–0.013 1 ∕ 4
Annealed 100 30.5 0.002 0.0005
0.05
0.013
1 ∕ 2
Alloy Steel
Hardened 70 21 0.002 0.0002–0.0005 0.05 0.005–0.013 1 ∕ 4
Annealed 60 18 0.002 0.0005 max.
0.05 0.013 max.
1 ∕ 2
Tool Steel
Hardened 50 15 0.002 0.0001–0.0005 0.05 0.003–0.013 1 ∕ 4
Annealed or Cold Drawn Cold Drawn or Solution Treated
Copper Alloys
100 30.5 0.002 0.0005 max.
0.05 0.013 max.
1 ∕ 6
1 ∕ 3
Aluminum Alloys
150 45.7 0.002 0.0005 max.
0.05 0.013 max.
1 ∕ 6
1 ∕ 3
Plunge Grinding, Infeed per Revolution of the Work
Inch
Millimeter
Work Material
Roughing
Finishing 0.0002 0.000050 0.000025
Roughing
Finishing
Steel, soft
0.0005 0.0002 0.0001
0.013 0.005 0.003
0.005 0.0013
Plain carbon steel, hardened Alloy and tool steel, hardened
0.00064 These data, which are, in general, considered conservative, are based on average operating conditions and may be modified subsequently by: a) reducing the values in case of unsatisfactory quality of the grinding or the occurrence of failures; and b) increasing the rates for raising the productivity of the process, particularly for rigid workpieces, substantial stock allowance, etc. High-Speed Cylindrical Grinding.— The maximum peripheral speed of the wheels in regular cylindrical grinding is generally 6500 feet per minute (1980 m/min); the com monly used grinding wheels and machines are designed to operate efficiently at this speed. Recently, efforts were made to raise the productivity of different grinding meth- ods, including cylindrical grinding, by increasing the peripheral speed of the grinding wheel to a substantially higher than traditional level, such as 12,000 feet per minute (3658 m/min) or more. Such methods are designated by the distinguishing term of high- speed grinding. For high-speed grinding, special grinding machines have been built with high dynamic stiffness and static rigidity, equipped with powerful drive motors, extra-strong spindles and bearings, reinforced wheel guards, etc., and using grinding wheels expressly made and tested for operating at high peripheral speeds. The higher stock-removal rate accomplished by high-speed grinding represents an advantage when the work configuration and material permit, and the removable stock allowance warrants its application. CAUTION: High-speed grinding must not be applied on standard types of equipment, such as general types of grinding machines and regular grinding wheels. Operating
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