Bond s law

For the size ranges involved, the crushing may be considered as intermediate and Bond s law will be used. 

Bond s law of particle size reduction provides an ostensibly more reasonable estimate of the power required to crush or grind a solid (46)... 

Combining Bond s work index [Eq. (27)] with Bond s law [Eq. (26)]... 

A third version of the comminution law is the one attributed to Bond (1952, 1963), who considered that the work necessary for reduction was inversely proportional to the square root of the size produced. In Bond s consideration, n takes the value of 3/2, giving the following version (Bond s law) also by integration of Equation 4.1 ... 

When Xi and X2 are measured in micrometers and E in kWh/ton, K = 5Ei, where E is the Bond Work Index, defined as the energy required to reduce a unit mass of material from an infinite particle size to a size such that 80% passes a 100 pm sieve. The Bond s work index is obtained from laboratory crushing tests on the feed material. Bond s law holds reasonably well for a variety of materials undergoing coarse, medium, and fine size reduction. 

Bond s Law. A theory of grinding which postulates that the grinding rate of a solid is proportional to the crack propagation speed in the solid. (F.C.Bond, Trans. Amer. Inst. Min. (metall) Engrs. 193,1952, p484). 

However, Bond s law is usually presented in the form shown in Equation (12.8b). The law is based on data which Bond obtained from industrial and laboratory scale processes involving many materials. 

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