Хонинговальные головки

Wheel manufacturers such as Universal Grinding Wheel (Saint-Gobain Abrasives) have taken this concept further, and produced wheels with multiple pore former size distributions to create both macroporosity for high permeability and microporosity for controlled fracture of the bond. This type of wheel, with trade names such as Poros 2, has proved very effective for creep-feed […]

Finally, for the roughest dressing of large cylindrical or centerless wheels there are grit tools and cluster impregnated tools (Figure 7.12). Grit tools represent the most cost-effective dressing tool for the commonest applications using straight wheels. Clusters consist of a single layer of five to seven large natural diamonds semiex­posed on a round flat surface […]

Diamond rolls are high-precision tools and must be treated as such. The following are recommended procedures for assembling a roll on a spindle shaft: • Standard roll/spindle assembly tolerances. Standard toleranced assemblies refer to rolls with bore tolerances of 2.5 to 7 pm over nominal mounting on shafts with nominal to 2.5 pm undersize, giving […]

Comparison of various international surface roughness systems is given in Table 2.1. 2.2.20 Factors That Affect Roughness Measurements Relative values between different roughness systems will vary by up to 20% depending on the metal-cutting process by which they were generated. Even when considering just grinding, the abrasive type can alter the ratio of Rz to […]

During grinding, the cutting edge of the grain penetrates the workpiece on a very flat path causing plastic flow of the material after a very short phase of elastic deformation. Since the angle between cutting edge contour and workpiece surface is very small due to the cutting edge rounding, no chip is formed initially. The […]

Wheels are speed tested by overspinning the wheel by a factor prescribed by the appropriate safety code for the country of use. In the U. S., ANSI B7.1 specifies that all wheels must be spin tested with an overspeed factor of 1.5 times the operating speed. The theory behind this reverts back to conventional wheel […]

3.3.1 Importance of Crystal Size A limitation of the electrofusion route is that the resulting abrasive crystal structure is very large; an abrasive grain may consist of only one to three crystals. Consequently, when grain fracture occurs, the resulting particle loss may be a large proportion of the whole grain. This results in inefficient grit […]

As with diamond, CBN grain grades are most commonly characterized by toughness and by shape. Toughness is measured both at room temperatures and at temperatures up to >1,000°C comparable to those used in wheel manufacture, the values being expressed in terms of a toughness index (TI) and thermal toughness index (TTI). The details of the […]

6.6.1 Introduction A number of considerations must be taken into account when selecting vitrified bond for diamond that places different demands relative to conventional wheels. These are primarily the effects of: Hard work materials Low chemical bonding High grinding forces Reactivity with air at high temperatures These considerations are discussed as follows. 6.6.2 Hard Work […]

In addition to the stationary tools for traverse dressing, full forms can be dressed simultaneously using form blocks. These are blocks that have a layer of diamond either sintered or directly plated and molded to the form required in the wheel. They are used especially in surface grinding where the block is set on the […]