Vigorously develop circular economy: the company adheres to the development path of circular economy, realizes the efficient utilization of energy and A514 grade Q quenched and tempered steel resources, implements "four closed circuits" for renewable gas, industrial water, solid waste and waste heat steam according to the reduction of resource consumption - reuse - recycling, vigorously promotes advanced technologies such as energy-saving new technologies, new processes, A514 grade Q quenched and tempered steel new materials, and promotes the competition of enterprises Struggle.
Design of smelting composition and smelting process of SN400A, SN400B, SN400C steel, A514 grade Q quenched and tempered steel product: The smelting process adopts low-sulfur molten iron and low-sulfur scrap on the basis of the general process flow of steel for export, adding the refining process of LIIF furnace deep desulfurization and SiCa treatment. In this way, the sulfur content in the steel can be reduced, and the sulfide in the steel can be modified. Greatly improve the toughness of steel and improve the casting performance of molten steel, and increase the qualification rate of the tundish temperature to ensure smooth casting.
A514 grade Q quenched and tempered steel, Q345D seamless pipe is low-alloy high-strength structural steel. It is named as low-alloy because of a small amount of alloy elements in the steel. Q345D seamless pipe is mainly used for construction and engineering structures. The carbon content of Q345D seamless pipe is ≤ 0.18%. Due to the effect of alloy elements, the yield strength of Q345D seamless pipe is 25% - 150% higher than that of carbon structural steel pipe with the same carbon content. Q345D seamless pipe can reduce the weight of steel structure, save steel products and effectively extend the service life of steel structure.
The sulfur element (S element) comes from the ore and fuel coke of steelmaking. It is a harmful element in A514 grade Q quenched and tempered steel etc. steel. Sulfur exists in steel in the form of iron sulfide (FeS). FeS and Fe form a low melting point (985℃) compound. The hot working temperature of steel is generally above 1150 - 1200℃, so when the steel is hot working, the premature melting of FeS compound causes the workpiece to crack, which is called "hot brittleness". It reduces ductility and toughness of steel and causes cracks during forging and rolling. Sulfur is also detrimental to welding performance and reduces corrosion resistance.
A514 grade Q quenched and tempered steel, Q345 and Q345B are steel numbers. The differences are as follows:1. Q345 is general and does not indicate the quality level; Q345B is clear and the quality level is B.2. Q345 does not require to inspect the impact performance; Q345B requires that the impact performance at room temperature is qualified (impact at 20 ℃).3. Q345 does not indicate carbon content of steel; Q345B carbon content is 0.20%.Q345 refers to carbon structural steel with yield point (σ s) of 345MPa. The following letters indicate the quality level, including A, B, C, D and E.
Keep close relationship with all manufacturers and users, cooperate sincerely, share weal and woe together. We are deeply tolerant of travelling with you! We value and value each other's career and friendship. No matter when and where, all our staff will spare no effort to put into the work, and do their best to provide A514 grade Q quenched and tempered steel satisfactory services for all friends, so as to achieve win-win and multi win for each other.
The company has passed the ISO9001: 2008 quality system certification, strictly implemented the ISO9001 quality management system. Besides, we have continuously improved the after-sales service network to make every effort to provide more convenient, accurate and faster services for all customers. We will supervise the production, control the quality in the factory, Inspect the cargo before shipment, Issue the test report to sales department. From the steel prodcution to steel delivery, we always focus the whole process.
