GB 5310 12Cr1MoVG High Pressure Boiler Tubes
GB 5310 12Cr1MoVG Seamless steel tubes and pipes for high pressure boiler
12Cr1MoVG is a Cr-Mo-V low alloy heat-resistant steel introduced from the Soviet Union in the 1950s and 1960s. Vanadium is an element that reduces the y-phase region. When dissolved in y-fe, it will inhibit the transformation of ADI to pearlite, which is beneficial to the formation of ADI. The total amount of alloy in 12Cr1MoVG steel is only one half of that of 2.25Cr-1Mo steel, but the endurance strength (580 ° C) is 1.4 times of that of 2.25Cr-1Mo steel. Similar steel grades widely used abroad include ASTM a405 p24 in the United States, bs3604 in the United Kingdom, DIN 13crmov42 in Germany, etc.
Manufacturing methods
(1)Steel smelting method
GB 5310 12Cr1MoVG steel will be smelted by electric furnace plus furnace refining, oxygen converter plus furnace refining or electroslag remelting method.
(2)Manufacturing methods and requirements for tube blanks
The tube blank can be produced by continuous casting, die casting or hot rolling (forging).
Forging and rolling: the initial forging temperature is 1180-1145 ℃, and the final forging temperature is greater than 850 ℃. After forging, stack cooling is required.
(3)Manufacturing method of steel tube
GB 5310 12Cr1MoVG Steel tubes shall be manufactured by hot rolling (extrusion, expansion) or cold drawing (rolling).
Cold and hot processing: small diameter steel pipes can be cold bent without heat treatment after bending. Large diameter thin-walled tube can be cold bent, after bending, it needs to do high temperature heat treatment. Large diameter thick wall pipe needs hot bending. The heating temperature of the hot bend is 980 ° C, and the final bending temperature is more than 800 ℃. After bending, it needs normalizing and adding back.
GB5310 12Cr1MoVG boiler steel pipe Chemical Composition and Mechanical Property
| Steel grade | 12Cr1MoVG Chemical composition(%) | |||||||
C | Mn | Si | V | Cr | Mo | P | S | ||
GB5310 | 12Cr1MoVG | 0.08~0.15 | 0.40~0.70 | 0.17~0.37 | 0.15-0.30 | 0.90-1.20 | 0.25~0.35 | ≤ 0.025 | ≤0.010 |
12Cr1MoVG Mechanical property | ||||
| Tensile strength (MPa) | Yield strength (MPa) | Elongation(%) | |
GB5310 | 12Cr1MoVG | 470~640 | ≥ 255 | ≥ 21 |
GB5310 12Cr1MoVG boiler steel pipe Application
12Cr1MoVG boiler steel pipe is used for high-pressure boilers heating surface tubes, economizer, superheater, reheater, petrochemical industrial pipe etc.