摘要 |
An earth boring shear bit having a plenum from which drilling fluid flows along passageways to the outside of the bit is made by positioning a plenum blank 509 in a mould, at least partially filling the remainder of the mould with matrix powder and binder and then sintering. The plenum blank 509 is made in a mould which in turn is formed using a pattern of the plenum. The pattern may be made using a computer aided manufacturing technique. Also a method of manufacturing an earth-boring shear bit having a plenum and at least one fluid pathway by modeling fluid flow through the plenum fluid pathway, determining a geometry to reduce fluid separation through the fluid pathway, constructing a plenum blank 509 based upon the model and sintering matrix powder between the plenum blank and a bit head mold to create the fluid plenum and at least one fluid pathway. |