Bond Work Test

Related Calculations. Although the Bond grindability test is run dry, the work index calculated above is for wet grinding. For dry grinding, the work index must be multiplied by a factor of 4/3. 

A crushability work index can also be empirically calculated. A Bond crushability test (based on striking the specimen with weights) indicates the crushing strength C per unit thickness of material, in foot pounds per inch. This is related to work index IT, in kilowatthours per ton, by the formula Wt = 2.59C/S, where S is the specific gravity. 

As the limestone must be ground to about 90 % less than 40 pm, it is important that the operating and capital costs of the grinding equipment should not be excessive. The Bond Work Index test [12.7] was developed as a measure of the ease with which a substance can be ground. The value of the index for many limestones is between 8 and 10 kW hr/short ton. 

Test Method for Limestone Grindability and Calculation of Bond Work Index", Method 7. In FGD Chemistry and Analytical Methods Handbook , Vol. 2, EPRI Report CS 3612, July 1984. 

Working Life of Liquid or Paste Adhesive by Consistency and Bond Strength. Test for (D 1338) ... 

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. 

Linus Pauling, an American chemist, was the first to take a closer look at the electrical difference of bonds. He tested the differences in energies of covalent bonds. In 1939, he published The Nature of the Chemical Bond which discussed the energy levels of molecules. Pauling was recognized for his work with protein structures. His electrochemical valency theory won the Nobel Prize for Chemistry in 1954. 

Linus Pauling (1901-1994) was born in Portland Ore gon and was educated at Oregon State University and at the California Institute of Technology where he earned a Ph D in chemistry in 1925 In addition to re search in bonding theory Pauling studied the structure of proteins and was awarded the Nobel Prize in chemistry for that work in 1954 Paul ing won a second Nobel Prize (the Peace Prize) in 1962 for his efforts to limit the testing of nuclear weapons He was one of only four scientists to have won two Nobel Prizes The first double winner was a woman Can you name her" ... 

Because of their greater thickness, CAA oxides serve to protect the metal surface from corrosion better than thinner oxides but the important factor for bond durability is the stability of the outer oxide structure when water diffuses to the oxide-polymer interphase. Accordingly, it would be expected that the performance of CAA treated adherends would be similar, although no better, than that of PAA, or BSAA. The wedge test data shown in Fig. 20 and other work [29,77,97,98] support this and demonstrate that when these processes are done correctly the wedge test crack will be forced to propagate entirely within the adhesive. Similar arguments are likely with BSAA adherends, also. 

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