Detailed introduction of 15CrMoG seamless steel pipe

Specifications and appearance quality of high-pressure boiler steel pipes:

GB/T5310-2017 "Seamless steel pipes for high-pressure boilers", according to different production processes, can be divided into: hot rolling, cold drawing, and hot expansion; single length is about 3-13 meters; can also be produced according to customer requirements. The outer diameter of hot-rolled boiler steel pipes is 22-1020mm, and the wall thickness varies from 2mm to 70mm. The outer diameter of cold-drawn (cold-rolled) pipes is 10~108mm, and the wall thickness varies from 2.0 to 13.0mm. The process for outer diameters greater than 508 is hot expansion;

Main grades of high-pressure boiler steel pipes:

10, 20, 20G, 20MnG, 25MnG, 15CrMoG, 12Cr2MoG, 12Cr1MoVG, 12Cr2MoWVTiB, 10Cr9Mo1VNb, SA210A1, SA210C, SA213 T11, SA213 T12, SA213 T22, SA213 T23, SA213 T91, SA213 T92, ST45.8/Ⅲ, 15Mo3, 13CrMo44, 10CrMo910, etc.

The manufacturing process of 15CrMoG seamless steel pipe: The raw material of boiler steel pipe is round tube billet, which is cut by a cutting machine into a billet with a length of about 1 meter and sent to the furnace for heating via a conveyor belt. The billet is sent into the furnace for heating at a temperature of about 1200℃. The fuel is hydrogen or acetylene. The temperature control in the furnace is the key issue. After the round tube billet is taken out of the furnace, it must be pierced by a pressure-piercing machine. Generally, the more common piercing machine is a tapered roller piercing machine, which has high production efficiency, good product quality, large piercing, and expansion, and can pierce a variety of steel types. After piercing, the round tube billet is successively subjected to three-roller oblique rolling, continuous rolling, or extrusion. After extrusion, it must be removed from the tube and sized. The sizing machine uses a conical drill bit to rotate at high speed into the steel billet to punch holes to form a steel pipe. The inner diameter of the steel pipe is determined by the outer diameter length of the sizing machine drill bit. After sizing, the steel pipe enters the cooling tower and is cooled by water spray. After cooling, the steel pipe must be straightened. After straightening, the steel pipe is sent to the metal flaw detector (or water pressure test) by a conveyor belt for internal flaw detection. If there are cracks, bubbles, and other problems inside the steel pipe, they will be detected. After quality inspection, the steel pipe must also pass strict manual selection. After the steel pipe is inspected, the number, specification, production batch number, etc. are sprayed with paint. And it is hoisted into the warehouse by a crane.

15CrMoG seamless steel pipe is a kind of boiler steel pipe, which belongs to the seamless steel pipe category. Its delivery state is normalizing + tempering; the manufacturing method is the same as that of seamless steel pipe, but there are strict requirements on the steel type used to manufacture steel pipes. High-pressure boiler steel pipes are often in high-temperature and high pressure conditions when used. Under the action of high-temperature flue gas and water vapor, the steel pipe will oxidize and corrode. The steel pipe is required to have high lasting strength, high oxidation and corrosion resistance, and good organizational stability. High-pressure boiler steel pipes are mainly used to manufacture superheater tubes, reheater tubes, gas guide tubes, main steam pipes, etc. of high-pressure and ultra-high-pressure boilers.