High-performance deep grinding, with increased wheel peripheral speed and increased feedrate, is a special case requiring a cooling lubricant supply system adapted in terms of pressure and volume flow capability [Rowe and Jin 2001]. Application limits for high-performance grinding result from wheel safety requirements, that is, the maximum admissible peripheral speeds for grinding wheels. These are approximately 125 m/s for grinding wheels with resin and vitrified bond. In the case of wheel peripheral speeds higher than 125 m/s, mainly CBN grinding wheels with sintered metal or plated metal bond in a metallic base body are used for steel materials. The advantages of highspeed grinding are higher surface quality, shorter machining times, lower wheel wear, and low grinding forces.
Table 16.2 compares typical process values for reciprocating, creep, and high-performance grinding [Minke and Tawakoli 1991]. In the case of creep and high-performance grinding, infeeds in the mm-range reach maximum values of approximately 30 mm. The specific material removal rates in the case of creep feed grinding differ within the range of the conventional values of Q’w = 3 to 5 mm3/(mm/s) [Minke and Tawakoli 1991].
Due to the higher grinding forces in high-performance grinding processes, more demanding requirements are placed on the grinding machine and machine system:
• Rigid concrete or superior stiff structural design
• Robust guiding elements
• Effective spindle drives and mountings
• Use-friendly cooling lubricant and cooling system
• Adapted grinding tools and dressing equipment
• Efficient control equipment
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TABLE 16.2 Process Parameters of Reciprocating, Creep, and High-Performance Grinding Processes
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