self-cleaning roller cone of drill bit

  • 1Hughes Christensen — Hughes Christensen, a division of Baker Hughes Inc., is a large oil and gas drill bit company. Howard Hughes, Sr. founded the company early in the 20th century. His two cone, rolling cutter rock bit whose patent was issued by the US Patent Office …

    Wikipedia

  • 2Wrench — For other uses, see Wrench (disambiguation). A set of chrome vanadium metric wrenches, open at one end, box/ring at the other. This type is commonly known as a combination wrench. A wrench or spanner is a tool used to provide grip and mechanical… …

    Wikipedia

  • 3Business and Industry Review — ▪ 1999 Introduction Overview        Annual Average Rates of Growth of Manufacturing Output, 1980 97, Table Pattern of Output, 1994 97, Table Index Numbers of Production, Employment, and Productivity in Manufacturing Industries, Table (For Annual… …

    Universalium

  • 4M1 Garand — Rifle, Caliber .30, M1 M1 Garand with en bloc clips. Type Semi automatic rifle Place of origin …

    Wikipedia