For 13 consecutive years, Zhang Yanchao's products have maintained the first-grade product rate of 100%, which has solved the problems of chatter and tool running in roll processing; Invent the "five-step working method" to ensure the consistency and stability of team members' products; Led the team to participate in the key task of the implementation of full-program one-key machining of CNC lathes, and contributed more than 50 innovative achievements. Entering the first workshop of the second processing plant of Xingtai Machinery Roll Co., Ltd. of Sinosteel Group, the machine boomed. In front of the CNC machine tool, Zhang Yanchao was completely absorbed, staring at the equipment in his hand. "The requirements for the processing size of the special hole of the roll are very strict, with a tolerance of only 0.046 mm," said Zhang Yanchao. Measure the size of the special hole, calculate the compensation value, input it on the operation panel program, and then start the machine tool program button... After a while, the roll "on" the machine tool will rotate at high speed. In the squeal of metal friction, spiral ribbons of iron filings fall off, and various forms of high platform, deep groove and round hole on the roller gradually appear, which is amazing. Roll is the most important part of rolling mill. "The thickness and shaping of steel depend on rollers." Zhang Yanchao said that a fine steel blank used to process rollers weighs more than ten tons and is worth hundreds of thousands or even hundreds of thousands of yuan. "As long as there is a little error in processing, the whole roll will be scrapped, resulting in very large losses." For this reason, Zhang Yanchao has strict requirements on himself, involving every link of roll processing, especially every step of data measurement, he has carefully worked out, changing the single confirmation into a double check, and realizing "zero error" through mutual inspection between different measuring tools. From 2010 to 2022, the products made by Zhang Yanchao maintained the first-grade product rate of 100% for 13 consecutive years. Zhang Yanchao first came into contact with roller work at the age of 21. In August 2007, after graduating from Hebei Mechanical and Electrical Vocational and Technical College, Zhang Yanchao came to China Steel Xingji for internship and became a roller operator. At the beginning, he followed his master to learn to repair and finish machining; One year later, he was officially employed; In 2017, he was exceptionally employed as the chief technician. Zhang Yanchao has been good at summarizing experience and constantly improving the process for many years. The operation of finishing machining process is an independent operation, and the team members "fight alone". "This may lead to the lack of unified management of different members in processing methods and quality control, the lack of close cooperation between the same process, and the weak overall quality control of the team," Zhang Yanchao said. How to change independent work into team cooperation? In 2016, Zhang Yanchao formulated a clear set of quality control requirements and management standards through work experience summary. According to his work experience, Zhang Yanchao subdivided the quality control process of finishing machining into 23 processing quality control nodes, and finally classified them into a "five-step work method" of "one preparation, two confirmation, three verification, four consistency and five musts". The "five-step working method" is helpful for the processors to form programmed operation actions during the operation process to ensure the consistency and stability of the products. After the formulation of the "five-step working method", Zhang Yanchao took the lead in promoting it in his own refined car class 8. Driven by him, for several consecutive years, the team members have achieved "zero error" in operation, the one-time inspection pass rate has reached 99.3%, and the first-grade product rate has reached 96%.