METHOD TO PRODUCE DRILLING BITS WITH PDC-PLATES Russian patent published in 2010 - IPC E21B10/46 B23H1/00 B23K35/22 

FIELD: process engineering.

SUBSTANCE: invention relates to drilling equipment and can be used in production of drilling bits furnished with polycrystalline-diamond plates (PDC). Proposed method comprises turning and milling of the body components, drilling ducts to feed flushing fluid from nit inner space to blades and cutting edges of rock-braking inserts with PDC-plates, machining seats for said plates, fitting graphite plugs in said seats, hard-facing the space between said plugs, withdrawing graphite plugs and fitting inserts with PDC-plates therein, and sealing off said inserts. Then sharp edges of flushing ducts, at their exit from drilling bit inner space, are upset by melting with hard-alloy electrode to produce annular chamfer-like site of round-oval shape, when duct section runs onto lateral surface of drilling bit that features flat, convex or concave surface. At the same time, produced surfaces are reinforced by hard-alloy electrode metal. Then drilling bit entire work and inner surfaces, including inner space and inner ducts, are cleaned, degreased for high-wear-resistant cluster coat to be electrochemically deposited thereon. Said chromium-based coat incorporates diamond microparticles and features thickness of 0.5 mm, micro hardness of up to 1200 kg/mm² with friction factor less than 0.09.

EFFECT: reliable protection of drilling bit body, its flushing ducts and rock-braking elements against abrasive wear and reduced balling.

6 dwg