Hebei Ranking Bit Manufacture Co,LTD is mainly engaged in the development of various series of bits,development,production and sales. Ranking company has developed and mass-produced products 3 inches to 26 inches series steel rock bit,various types of PDC bits,core bit and production and processing assembly 0.6m to 3m large diameter hole openers.Widely used in the oil,natural gas,hydrology,address,ore drilling engineering,product marketing the country and 20 countries and regions in the world. Ranking various rock bits,to ensure full compliance with all the terms and standard of American Petroleum Institute API specification,design,manufacturing and production and to ensure full compliance with the API specification requirements and content. Less