Among the many economic and technical indicators in the steelmaking process, steel consumption is the most important comprehensive economic and technical indicator in the steelmaking process, which generally accounts for more than 80% of the production cost of the converter. Under the current severe market situation, optimizing the steel consumption index is a key link for enterprises to reduce costs and increase benefits, and plays an important role in improving the competitiveness of the product market.

Since the third quarter, Hebei Xinda Iron and Steel steelmaking plant has continued to work on the main line of "improving quality and reducing cost", adhering to the goal of full staff as the basis, the whole system as the carrier, and full efficiency, focusing on the steel material consumption indicators, and realizing the breakthrough of process indicators, the improvement of product quality, and the reduction of cost through advanced standardization, optimization of process technology, and improvement of equipment function accuracy. Continue to reduce production costs by breaking the game. In July 2023, the consumption of steel material was reduced by 5.17kg/t, and the consumption of solvent material was reduced by 22.82kg/t, with a monthly effect of 45.4016 million yuan, and the cost reduction work achieved remarkable results!

Scientific steelmaking

01 Reduce steel consumption

Focus on the target task, take the initiative to solve the problem. In the face of the challenge goal of cost reduction and efficiency increase proposed by the company, the steel mill actively explored the optimization process method according to the concept of "all around the converter dry, to serve the converter operation", and set up a special research group on steel material consumption led by the director Ren Haibing and the participation of middle-level cadres and technical backbone. Study the solution item by item to achieve full coverage of converter, continuous casting and other areas. Through a series of measures such as low-slag smelting, slag steel recovery, temperature composition optimization control, and other iron-containing material addition timing selection, converter spatter control, and reduction of final slag TFe, the steel material consumption in July was reduced by 4.55kg/t compared with the monthly target plan, while the consumption of hot metal continued to decrease, reaching a good level, and achieving periodic results.

All the cadres and workers of the steel mill solve the problem in the practical work, unify the thinking in solving the problem, and overcome the fear of "stopping and avoiding" when they encountered problems in the past. Now create a "do not look for the factory director to find the scene, the eyes to find insufficient, rely on data to find leaks, dig the potential of the first line" a good atmosphere, the majority of cadres and workers have lamented, "originally encountered difficult problems did not dare to do, now is to do everything possible to prove that I am capable."

Smart steelmaking

02 Create a material heat balance calculation model

Investigation and research is the source of insightful insights and the basic skill of doing a good job. In order to reduce the consumption cost of auxiliary materials in the steelmaking process, Ren Haibing, the director of the steelmaking plant, led the technical backbones to carry out in-depth field research, formulated the technical plan of reblowing in full furnace service according to the on-site production practice, carried out experiments and explored, further optimized the calculation model of smelting material balance and heat balance combined with the theoretical knowledge of steelmaking, guided the blowing operation of the converter, and significantly improved the overall operation level of the converter. The total iron of converter slag decreased by 2.57% compared with the first quarter, reducing the loss of steel material by 2.67kg/t, and reducing the cost by 4.9643 million yuan /t.
In addition, the steelmaking plant also put the iron and steel work into practice, with the concept of "quality stability is the best way to reduce the iron to steel ratio", through the introduction of ladle cover, scrap baking and other processes, optimize the converter and continuous casting process, stabilize the converter smelting operation, minimize the heat loss of each link, and lay a solid foundation for reducing iron consumption and steel consumption.

Benchmarking advanced

03 Reduce the refining cost of Q195L steel grade

In order to further reduce the refining cost of Q195L steel grade, the steel mill has organized technical personnel to study the standard of the surrounding peer enterprises, and improve and optimize by learning from their process control experience and combining with the actual situation of steelmaking production. In the converter, the slag material is reasonably added according to the heat balance calculation, stable operation, control splashing, reduce the oxidation of molten steel, and the total iron in the slag is controlled below 18%; In terms of refining, according to the condition of converter molten steel, aluminum wire and aluminum particles are used to deoxidize slag making process, AD powder is used to replace part of aluminum material for deoxidizing slag making process. Meanwhile, the composition of molten steel and slag making process are adjusted according to the actual situation to prevent the composition control and continuous casting flocculation. Slab continuous casting further protection casting, including large ladle, medium ladle nozzle and argon seal, reduce alloying element burning loss. Through strict control of the material structure, deoxidation mode and key control points in the production process, the steel mill reduces the consumption of deoxidizer, alloy consumption, slag consumption, energy and power consumption and improves the quality of the casting billet, achieving a cost reduction of more than 105.4 yuan /t per ton of steel.

Equipment management

04 Improve product quality

In this era of winning by quality, we must have the spirit of pursuing the ultimate in quality. From cadres to grass-roots workers in steel mills, they always uphold the "heart of awe" for quality, strictly grasp the lifeline of product quality, and firmly carry out basic work from the source. In equipment management, steel mills dare to break the equipment management mindset, have the courage to face the problem and solve the problem. Strictly regulate equipment three-point inspection, enhance maintenance planning, clarify equipment TPM and equipment lean management ideas, and focus on daily minor work such as lubrication and fastening. When the continuous casting machine is shut down, the mold vibration level is checked and adjusted, and the control error is within ±0.5mm; When replacing the draw-straightening machine and the secondary cooling support roll, it is necessary to carry out radian check to improve the accuracy of the casting machine. Reasonable use of downtime maintenance time, each section of the water nozzle to measure and verify, do a good job of secondary cooling, to ensure that the spray distance of each section of the water nozzle to the casting blank is uniform and the water spray can cover the surface of the casting blank evenly, for the stable quality of the casting blank escort.

"The cost can be further reduced", "we optimize and optimize", such a dialogue in the production line of steel mills has become the focus of the sentence, from the factory to the workshop, and then to the workshop, the team, to promote the implementation of one cost reduction project after another, and continue to produce fruitful results in cost reduction and efficiency. In the next step, steel mills will always take production index control as the main line, based on production safety and stability, and strengthen standardized operation as the basic requirements, continue to adhere to the general policy of "iron before grasping the cost, steel after grasping the quality" unwavering, efficiency first, gathering "breakthrough" force, to break through conventional courage and courage, solid and powerful cost reduction and efficiency measures, and constantly innovate ideas and methods. To the production organization process to benefit, to ensure that the key indicators to make new breakthroughs, high-quality and efficient to promote the company's cost reduction and efficiency work to a new level!