... .Increase output of 30%-50% 5. ISO 9001:200 high strength proppant bauxiteIntertek Refractories Co., Gongyi City, founded in 2001 ... hometown of refractories - Henan Gongyi.The company has strong technical force and advanced production testing equipment, has a production ... , innovation, more than 50 existing types of technical personnel, has developed a high-density, medium density, low density and many ...