... *114-610mm*6-12m material:12Cr1MoV, 15CrMo, 20G, etc seamless steel boiler tubes Standard: GB5310-2008 Material: 15CrMo, 12Cr1MoVG, 20G, 12Cr1MoV, 16Mn ... : 6-12m Application: high pressure boiler pipe, low and medium steel boiler pipe. Packing: in bundle, black painted, or as required ...