Dajin International (Group) Co., Ltd
drilling tools, magnesium,investment casting
DAJIN INTERNATIONAL(GROUP)CO., LTD.(Short form :DAJIN GROUP) is one large scale comprehensive trading and industrial corporation in the line of international trade, which established according to modern enterprise system and is the leading I/E Co.
The main products of DAJIN INTERNATIONAL (GROUP) CO., LTD are all kinds of petroleum drilling tools including drill collar, heavy wall drill pipe, kelly, stabilizer, non-magnetic drill tools, cross-over sub, bit subs and float subs, pup joint, downhole motor, turbine motor, bent joint, check valve, drilling jar, and so on.
Our drilling tools are made from premium chromium molybdenum alloy steel in accordance with API spec.7 and API RP7G, residual elements such as sulphur and phosphorous is reduced during the steel making process that make the kind of material with high physical properties.
Heat treatment is a decisive process in the production of drill tools. Heat treatment must be uniform and deep enough to ensure required physical properties in critical threaded sections. Heat treatment programs are established, which are based on the actual chemical analysis of each heat of steel to ensure the materials meet or surpass the requirements of API specification.
Thread is the most important factor for drilling string. All threads would be machined with CNC lathes and inspected with related threads would be phosphated or copperized and the roots cold rolled. All connections would be equipped with pressed steel thread protectors.
Quality control is performed strictly with requirement of API QI and ISO9002. We established a standard Inspection laboratory Center for physical and chemical testing. All testing information obtained is recorded on our inspection certificate furnished with each product, and all inspectors must have relevant qualification.
API making and monogram, API monogram, serial number, OD, ID, type and size of connections are stamped on recessed mill flat up to requirement of API specification.
To meet the need of prosperous development of global oil industry, we are sincerely expecting broad cooperation with worldwide friends to develop advanced drilling tools and facilities together.