Northwest Aluminum overcomes the difficulties in the production and Technology of High-end Aeronautical Aluminum Alloy Forgings to achieve prosperous production and sales of forgings

The processing of high-end aviation aluminum alloy forgings is a new profit growth point of Northwest Aluminum Co., Ltd. (hereinafter referred to as Northwest Aluminum), and it is also an important measure taken by Northwest Aluminum to implement the leapfrog development strategy, develop deep processing based on material advantages, and realize transformation and upgrading, and further extend to the high end of the value chain and the terminal of the industrial chain.

For a long time, the Northwest Aluminum Deep processing Center has adhered to the business concept of "1123" and gradually made the transition from black processing and forging to non-ferrous processing and forging. Out of a "from zero to have" and "from have to good" test, summary, re-test, re-summary of the road of innovation and research and development, and overcome a number of technical difficulties, to achieve mass production. In 2021, Northwest Aluminum completed the processing tasks of hundreds of high-quality aluminum alloy forgings used in high-end aerospace, ships, warships, machinery manufacturing and other fields, with an output of more than 200 tons for the first time, a record high output of forgings. compared with the same period last year, the output increased by nearly 10 times, and the rate of finished products increased by 10 percentage points.

A clear train of thought in dealing with difficulties

Reasonable forging temperature is the key to the success of aluminum alloy forging process. In the process of processing, if the forging temperature of aluminum alloy billet is reasonable, the deformation resistance is small, the plasticity is good, and the forging structure quality is relatively stable and uniform; if the billet temperature is too high, it is easy to cause coarse grain or even overburn, resulting in quality instability; if the billet forging temperature is too low, the deformation resistance increases, the malleability is poor, and coarse grains are easy to be produced. Therefore, in the northern winter with low temperature and large temperature difference between day and night, it is not suitable for batch forging.

If you have the conditions, you have to go up, even if you don't have the conditions to create them. Facing the challenge of urgent processing tasks, many specifications and long processing time, Liu Jinhai, the leader of the labor model innovation room in charge of the project, organized engineers and technicians to hold a special topic and said: "the temperature of the forging plant is only ten degrees below zero. If we do not take effective measures to control the temperature, it may eventually affect the plastic and mechanical properties of forging billet products, which is not conducive to long-period and batch operations. Therefore, it is necessary to adopt constant temperature technical innovation and ideas to control the temperature in the processing process. "

Do it in a down-to-earth manner and do it right away. Through comparative analysis, the relevant staff are determined to increase the temperature in the forging process and reduce the temperature loss in the processing process. This scheme is difficult and technically demanding, but the effect may be more obvious.

The first trial of constant temperature forging "Niudao"

There is a goal in decision-making and a guarantee in action. The transformation of the "battle to attack the fortified ground" has begun. The 800-ton die forging machine of Northwest Aluminum is a new generation of digital, intelligent and automatic production equipment, which requires high precision for operators. The transformation work should not only ensure that the temperature can be controlled at any time after the transformation, but also realize the "data sharing" of heating and constant temperature devices according to the characteristics of narrow working space and size. To this end, Huang Xiaohua, a senior engineer, led the electric fitters to climb up and down to carry out technical transformation on the fixing device of the hammer drill under the die forging machine.

Ideas determine the way out, and details determine success or failure. After a week of detailed design and machining testing, the modified forging billet can be processed in a relatively constant temperature environment, so as to prevent forging defects and unqualified properties caused by rapid temperature drop. The quality process control of forging processing is greatly improved.

7 series aluminum alloy has the stress structure of high strength and high corrosion resistance, so it is regarded as the best product of "replacing steel with aluminum" in this century. Because of the characteristics of high strength and high hardness, the processing of this product is very difficult, which is completely different from the concept, methods and methods of trial production of ordinary aluminum alloy. If there is no constant temperature forging equipment renewal and transformation, it is inconceivable to realize the batch processing of "7 series" alloy in such a large temperature difference environment. In January, Northwest Aluminum completed the processing of 785 products of 9 specifications of "7 series" alloy. Now the working efficiency of "constant temperature forging" is good, the processing process is stable, and the cumulative delivery is 21 tons.

Value creation and expansion specifications

Take on the mission and move forward bravely. The obvious effect of "Niudao" in the initial test of constant temperature forging was summarized by the relevant staff in time, and decided to use the machine to develop larger "6 series" products. In the early stage, the trial production of forging billets with specifications above 500mm often requires secondary heating processing, resulting in part of the process indicators or technical performance is not up to standard, affecting product quality, and even resulting in waste products. Wang Xiaopeng, the monitor of the forging class and the leader of the party commando, is the "responsible person" for the production of forgings. He drives the staff and workers of the team to give full play to the advantages of platforms such as "one specialty and multiple abilities", "mentors and apprentices" and "technical seminars", and regularly exchanges their experiences and technical know-how every month, thus promoting the technological growth of newly transferred personnel. In the face of the "big guys" of the newly developed 500mm and above, he pointed out that the processing of each product is about 100 jin, requiring more than a dozen processes such as lifting, turning, rolling, forging, leveling, and measuring, with heavy billet load and long processing time, and each post personnel should not be negligent, pay attention to the essentials of work and safe operation, and improve efficiency. The team thought of "a game of chess", carried out "drive, quality, efficiency" of the "three-ratio" activities, the enthusiasm of the staff is high, and the processing site is in good order.

At present, the R & D progress of larger size forgings of Northwest Aluminum is smooth, and the one-time forging is completed in the processing process, which greatly improves the rate of finished products and reduces the cost of the original "secondary" heating process. it provides a powerful exploration and practice to realize value creation based on the original equipment, and makes a positive contribution to energy saving, carbon reduction and efficiency improvement of Northwest Aluminum.