Hot-rolling seamless steel pipe applicable to high temperature of 580-620 DEG C and high pressure of 24-30MPa and production method thereof

The invention provides a hot-rolling seamless steel pipe applicable to high temperature of 580-620 DEG C and high pressure of 24-30MPa and a production method thereof. The steel pipe comprises the components by weight percentage of 0.08-0.12% of C, 0.20-0.50% of Si, 0.30-0.60% of Mn, 0-0.020% of P, 0-0.010% of S, 0-0.40% of Ni, 8.00-9.50% of Cr, 0.85-1.05% of Mo, 0-0.20% of Cu, 0-0.015% of Al, 0.18-0.25% of V, 0.06-0.10% of Nb, 0.030-0.070% of N and the balance of Fe. Simultaneously, the invention also provides the production method for producing the hot-rolling seamless steel pipe. The steelpipe and the production method have the effects that the performance of the steel pipe completely meets the requirement of ASME SA-335M standard on the tension and hardness and meets the requirement of GB5310 on impacting and duration strength, the steel pipe has excellent high-temperature performance, is applicable to the high-temperature bearing parts such as a steam pipeline, a connecting box and ...

Pre-deoxidation recarburization process for arc furnace steel-smelting molten steel with slag

The invention relates to a pre-deoxidation and carburization craft of molten steel with slag in the electric-arc steelmaking furnace, comprising the following steps: (1) charging; (2) electrifying melting; (3) oxygen blowing to boost melting; (4) oxidation refining; (5) temperature measuring and sampling; (6) addition of deoxidizer (7) tapping. The pre-deoxidation and carburization craft of molten steel with slag in the electric-arc steelmaking furnace solves the problems in the prior art of high oxidation of molten steel in the electric-arc steelmaking furnace and low carbon content. The pre-deoxidation and carburization craft of molten steel with slag in the electric-arc steelmaking furnace has the advantages that: 1. the craft has easy operation and obvious effect. The carbon content of the steel in the electric furnace is increased, the oxygen content in molten steel is decreased and over-oxidation of the molten steel is avoided. 2. the addition of deoxidizer used for the molten steel ...

Seamless steel tube for petroleum cracking and heat treatment method thereof

The invention provides a seamless steel tube for petroleum cracking. The steel tube comprises the following components in percentage by weight: 0.08 to 0.15 percent of C, 0.20 to 0.50 percent of Si, 0.30 to 0.60 percent of Mn, less than or equal to 0.020 percent of P, less than or equal to 0.020 percent of S, less than or equal to 0.20 percent of Ni, 4.00 to 6.00 percent of Cr, 0.40 to 0.55 percent of Mo, less than or equal to 0.20 percent of Cu, less than or equal to 0.015 percent of Al, less than or equal to 0.08 percent of V, less than or equal to 0.01 percent of Nb, less than or equal to 0.008 percent of N, and the balance of Fe. The invention also provides a normalizing and tempering heat treatment process for producing the seamless steel tube. The invention has the advantages that: the steel tube is subjected to heat treatment by strictly controlling chemical compositions and adopting a heat treatment system beyond a GB9948 standard, various properties of the steel tube which issubjected ...

Hot-rolling seamless steel pipe applicable to high temperature of 580-620 DEG C and high pressure of 24-30MPa and production method thereof

The invention provides a hot-rolling seamless steel pipe applicable to high temperature of 580-620 DEG C and high pressure of 24-30MPa and a production method thereof. The steel pipe comprises the components by weight percentage of 0.08-0.12% of C, 0.20-0.50% of Si, 0.30-0.60% of Mn, 0-0.020% of P, 0-0.010% of S, 0-0.40% of Ni, 8.00-9.50% of Cr, 0.85-1.05% of Mo, 0-0.20% of Cu, 0-0.015% of Al, 0.18-0.25% of V, 0.06-0.10% of Nb, 0.030-0.070% of N and the balance of Fe. Simultaneously, the invention also provides the production method for producing the hot-rolling seamless steel pipe. The steelpipe and the production method have the effects that the performance of the steel pipe completely meets the requirement of ASME SA-335M standard on the tension and hardness and meets the requirement of GB5310 on impacting and duration strength, the steel pipe has excellent high-temperature performance, is applicable to the high-temperature bearing parts such as a steam pipeline, a connecting box and ...

Calcium treatment method for molten steel in steel making

The invention provides a calcium treatment method for molten steel in steel making, which comprises the steps of: melting steel in an electric furnace, tapping and pre-deoxidizing, conducting calcium treatment to the molten steel and stirring to cause impurities to float up. After the calcium treatment, the compound impurities in the molten steel is easy to float up after being stirred; the impurities with a diameter less than 10 mum, which collide with each other and grow up with bottom argon stirring in the course of refining, can also float up and be eliminated . The method has the advantages that the adoption of calcium treatment method for molten steel in steel making plays a good role in reducing the impurities in the molten steel; the impurities super-long heat is obviously reducedfrom originally 6-10 furnaces per month to currently less than 2 furnaces per month; the rating of class-B impurities decrease totally; level 0 and level 0.5 together account for 97.2%; B refinement is ...

Bearing fault diagnosis device

A bearing fault diagnosis device disclosed by the present invention comprises a transmission structure, a mechanical direction adjusting structure and a detection box arranged on the side surface of the transmission structure, the transmission structure comprises a bottom backing plate, the top of the bottom backing plate is connected with a transmission guide rail, a sliding block is embedded in the inner side of the transmission guide rail, and the top of the sliding block is connected with a bearing plate. A bearing detection structure is arranged at the top of the bearing plate, a detection plate is arranged on the side face of the bottom base plate and is of a cuboid structure, two image collection discs are arranged on the inner wall of the detection plate at intervals and right face the bearing detection structure, and the two mechanical direction adjusting structures are located opposite to the detection plate. The bearing fault diagnosis device provided by the invention can effectively ...

Experiment monitoring method and device for movable gearbox

The invention discloses an experiment monitoring method and device for a movable gearbox. The method comprises the steps that a motor and the gearbox are fixed to a movable trolley; an experiment monitoring circuit is connected through a disconnecting switch; adjusting the input current of the motor through the frequency converter; through a resistance strain gauge installed on the surface of the gear box, the deformation quantity of a gear box shell after the gear box runs is detected; the change condition of the internal pressure is detected through a barometer mounted on the gear box; the temperature sensor fixedly connected with the gear box is used for detecting the temperature change of the gear box during operation. According to the experiment monitoring method for the movable gear box, daily operation parameters of the gear box can be tracked, the current life cycle of equipment of the same series can be predicted, and data support is provided for preventive overhaul and part replacement ...

Calcium treatment method for molten steel in steel making

The invention provides a calcium treatment method for molten steel in steel making, which comprises the steps of: melting steel in an electric furnace, tapping and pre-deoxidizing, conducting calcium treatment to the molten steel and stirring to cause impurities to float up. After the calcium treatment, the compound impurities in the molten steel is easy to float up after being stirred; the impurities with a diameter less than 10 mum, which collide with each other and grow up with bottom argon stirring in the course of refining, can also float up and be eliminated . The method has the advantages that the adoption of calcium treatment method for molten steel in steel making plays a good role in reducing the impurities in the molten steel; the impurities super-long heat is obviously reduced from originally 6-10 furnaces per month to currently less than 2 furnaces per month; the rating of class-B impurities decrease totally; level 0 and level 0.5 together account for 97.2%; B refinement is ...

Dry spinning process of making bright polyacrylic fibre