Machinery's Handbook, 31st Edition
SURFACE GRINDING 1329 Table 2b. Grinding Wheel Recommendations for Surface Grinding—Using Type 2 Cylinder Wheels, Type 6 Cup Wheels, and Wheel Segments Material Type 2 Cylinder Wheels Type 6 Cup Wheels Wheel Segments High tensile cast iron and nonferrous metals 37C24-HKV 37C24-HVK 37C24-HVK Soft steel, malleable cast iron, steel castings, boiler plate 23A24-I8VBE
23A24-I8VBE or 23A30-G12VBEP 32A46-G8VBE or 32A36-E12VBEP 32A46-H8VBE 23A30-H8VBE or 23A30-E12VBEP
23A24-I8VSM or 23A30-H12VSM 32A36-G8VBE or 32A46-E12VBEP 32A46-G8VBE or 32A60-G12VBEP 23A30-H8VSM or 23A30-G12VSM
Hardened steel—broad contact Hardened steel—narrow contact or interrupt cut
32A46-G8VBE or 32A60-E12VBEP 32A60-H8VBE
General-purpose use
…
Process Data for Surface Grinding.— In surface grinding, similarly to other metal-cut ting processes, the speed and feed rates that are applied must be adjusted to the operational conditions as well as to the objectives of the process. Grinding differs, however, from other types of metal cutting methods in regard to the cutting speed of the tool; the periph- eral speed of the grinding wheel is maintained within a narrow range, generally 5500 to 6500 surface feet per minute. Speed ranges different from the common one are used in particular processes which require special wheels and equipment.
Table 3. Basic Process Data for Peripheral Surface Grinding on Reciprocating Table Surface Grinders
Downfeed, in. per pass
Crossfeed per pass, fraction of wheel width
Hardness (Brinell/ Rockwell)
Wheel Speed, fpm
Table Speed, fpm
Work Material
Material Condition
Finish, max.
Rough
52 RC max. Annealed, cold drawn
5500-6500 50-100 0.003 0.0005
1 ∕ 4
Plain carbon steel
52-65 RC Carburized and/or quenched and tempered 5500-6500 50-100 0.003 0.0005
1 ∕
10
52 RC max. Annealed or
1 ∕ 4
quenched and tempered 5500-6500 50-100 0.003 0.001
Alloy steels
52-65 RC Carburized and/or quenched and tempered 5500-6500 50-100 0.003 0.0005
1 ∕ 10
150-275 BHN Annealed
5500-6500 50-100 0.002 0.0005
1 ∕ 5
Tool steels
56-65 RC Quenched and tempered 5500-6500 50-100 0.002 0.0005
1 ∕ 10
200-350 BHN Normalized, annealed
5500-6500 50-100 0.003 0.001 5500-6500 50-100 0.003 0.0005 5500-6500 50-100 0.003 0.001
1 ∕ 4
Nitriding steels
60-65 RC Nitrided
1 ∕ 10
52 RC max. Normalized, annealed
1 ∕ 4
Cast steels
Over 52 RC Carburized and/or quenched and tempered 5500-6500 50-100 0.003 0.0005
1 ∕ 10
52 RC max. As cast, annealed, and/or 52 RC max. As cast, annealed or
Gray irons
1 ∕ 3
quenched and tempered 5000-6500 50-100 0.003 0.001
Ductile irons
1 ∕ 5 1 ∕ 4 1 ∕ 8 1 ∕ 3
quenched and tempered 5500-6500 50-100 0.003 0.001
135-235 BHN Annealed or cold drawn 5500-6500 50-100 0.002 0.0005 Over 275 BHN Quenched and tempered 5500-6500 50-100 0.001 0.0005
Stainless steels, martensitic
Aluminum alloys
30-150 BHN As cast, cold drawn or treated
5500-6500 50-100 0.003 0.001
In establishing the proper process values for grinding, of prime consideration are the work material, its condition, and the type of operation (roughing or finishing). Table 3 gives basic process data for peripheral surface grinding on reciprocating table surface
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