Хонинговальные головки

As with all new technologies, it took significant time and application knowledge to understand how to apply SG. The abrasive was so tough that it had to be blended with regular fused abrasive at levels as low as 5% to avoid excessive grinding forces. Typical blends are now • 5SG (50%) • 3SG (30%) • […]

Interestingly, GE also developed a grit-type GE 550 that is a microcrystalline product; this could be considered the “SG” of CBN grains. It is extremely tough and blocky and wears by microfrac­turing. However, just like SG grains, it also generates high grinding forces and is, therefore, limited to use in the strongest bonds, such as […]

Diamond reacts with air at temperatures above 650°C. Therefore, the wheels must either be fired at low temperatures, or in an inert, or reducing, atmosphere. Very low temperature bonds, however, FIGURE 6.10 Hot pressed fully densified vitrified diamond bond structure. FIGURE 6.11 Typical application for a porous vitrified fine grain diamond structure wheel-grinding of polycrystalling […]

7.4.1 Introduction Rotary diamond tools were the industry’s answer to life issues with stationary tools and are in many ways the rotary equivalents to single points, blades, grit tools, and form blocks. A rotary diamond tool (also called “truer,” “dresser,” or “roll”) consists of a disc with diamond in some form held on the periphery […]

Out-of-balance and eccentricity of the grinding wheel are the main causes of forced vibrations [Inasaki and Yonetsu 1969, Gawlak 1984]. The wheel, as a source of vibration, can be relatively easily identified through frequency measurement. The main concern with wheel-induced vibration is how to eliminate out-of-balance and wheel runout. There are a number of other […]

Grinding, once considered primarily a finishing operation involving low rates of removal, has evolved as a major competitor to cutting, as the term “abrasive machining” suggests. This is what Milton Shaw, the man who is considered the great pioneer and father of American grinding, said about 10 years ago. Shaw led the development of grinding […]

When the infeed reaches its final feed point, the grinding force F will change with time t as the system relaxes according to the equation Ft and power are directly related; therefore t can be determined from a log plot of the decay in power during spark-out. After 3t virtually all grinding has ceased, preventing […]

When a scratching tool enters a fine-grained material, an entry section is formed by pure plastic deformation. The length of the entry section strongly depends on the corner radius of the diamond. If the material-specific shear stress is exceeded due to increasing scratching depth, a permanent deformation occurs thrusting aside the material and causing bulgings […]

Fm = Ms g/ 4.6.3.1 Clamping Force for Unbalance of the Wheel Fu = 8 Vs2 /rs2 Vb where 8 = unbalance (force. distance) vs = wheel speed rs = wheel radius 4.6.3.2 Clamping Force for Motor Power Surge It is assumed that electric motors can develop a surge torque of 2.5 times their rated […]

Direct comparison of the performance of SG and Cubitron is difficult because the grain is merely one component of the grinding wheel. SG is harder (21 GPa) than Cubitron (19 GPa). Anecdotal evidence in the field suggests that wheels made from SG give longer life but Cubitron is freer — cutting. This can make Cubitron […]