The object of this report is to define the classification, to explain the manufacturing process and to discuss the factors that must be considered in order to determine, under different operating conditions, the advantages and disadvantages of the bits.
In generally speaking, the use of detachable bits, which is continually expanding, is no longer confined to small mines and contractors. Although such bits are now manufactured from high-carbon steel, which.has greatly improved their quality, yet they must be considered as, being in the development stage still.
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