standard specification for seamless carbon steel boiler tubes for high-pressur

Internal and external walls without oxide layer

to withstand high pressure without leakage

Cold bending deformation

Flattening without cracks

best bright finish

Delivery condition:1. NBK(+N)after cold forming, eventually above phase transition point, in a protective atmosphere of annealing oxidation medium2. GBK(+A)after cold forming, annealing in non oxidizing medium protective gas3. BK(+C)the final heat treatment after cold forming, therefore small steel pipe plastically, the plastically degree does not guarantee4. BKW(+LC)after final heat treatment, a tiny cold drawing deformation, continue again when machining steel pipe allowed inside certain limits cold deformation(bending, flaring)5. BKS(+SR)have a stress relief after cold forming, heat treatment, steel pipe can be carried out within a certain limit in the appropriate processing again

TIANJIN DALIPU OIL COUNTRY TUBULAR GOODS CO.,LTD is a modern professional industry and trade combined enterprise specializing in producing and trading seamless steel pipes.The main products of our company are the oil casings and oil pipelines. We not only supply our goods with many large oil fields, but also establish a long-term business relationship with the Middle East Europe, Africa and other countries around the world and co-operative very well.