Profile: Ling Zhiyong has been engaged in melting work since joining Yulin Power Machinery Plant (now Yuchai) from the countryside in August 1969. He was appointed by Yuchai Group as melting master for consecutive years from 2003 to 2010 and chief foundry master, one of the five chief skill masters, in 2010; was ranked among national model workers in 2000.

All my disciples have learned my skills. All these are my disciples and followers, and many of them are more outstanding than me. One day in late March, the reporters saw the prestigious melting master Ling Zhiyong in the bustling foundry shop of Yuchai. He, who is steadfast and humble, now needs only to move about and observe, duly find abnormalities and instruct workers in settling problems. A 15-ton intermediate frequency furnace and a 12-ton cupola made a roaring sound of flames and produced red-hot liquid iron every ten minutes. The young guys operated skillfully and easily on the locomotive, getting liquid iron, pouringthe ladle lip and pouring cup fitted perfectly, and few sparks splashed. Ling called it once-off pouring, an astonishing manufacturing skill in Guangxi as well as another miracle created by the melting master.

Ling marveled at the happiness of Yuchais current workers, gone are the days when rattan hat is the only protective equipment. Yuchai now boasts the countrys most advanced casting line, workers need only to sit in casting machines with air-conditioners, and sparks will never splash people any longer.

Learning that the reporters came here because they admired the sharp sight of the melting master, Ling smiled simply. He rolled his sleeves up, saying, Did you see the scars on my arms? There are hundreds of scars in all sizes caused by splashing sparks of liquid iron, and my skills were trained this way.

According to Ling, foundry, especially the training of four basic skills in the process of liquid iron melting-composition, temperature, melting speed and coke consumption are not mastered in a day.

He recollected that he was employed from the countryside by then Yulin Power Machinery Plant (now Yuchai) as a first-line worker and one of the first workers of the foundry plant in August 1969. From then on, we was deeply impressed by the responsibility, devotion, scrupulousness, strictness and preciseness of the plant leaders and workmates, and decided secretly to be a devoted and accomplished foundry worker.

In the past four decades, Ling put his heart into cupolas, revolved around the four basic data of cupolas every day, and kept researching, modifying and optimizing. He worked by day and read professional melting books by night to thoroughly study the composition, temperature, melting speed and coke consumption as well as their relations. Over the years, he dug into these tedious data every day, made bold innovation and achieved remarkable effects on his post. If a cupola originally produces 100 tons of liquid iron with 20 tons of coke, it can produce the same amount with 16 or 18 tons when composition, temperature and melting speed are stable after modification, which is coke consumption reduction. Constantly striving to reduce coke consumption to leave cupolas in a rational and desirable state is the reason why Ling is crazy for cupolas.

Ling invented and made hollow preheating block of intermediate frequency furnace in 2007, which could save a cost of over RMB 100,000 for the purchase of preheating blocks a year. He organized and instructed in the technical breakthrough of iron-coke ratio, which has now increased from 4:1 before 2007 to over 6:1 now, namely, each kilogram of coke can melt two more kilograms of liquid iron. If 80,000 tons of liquid iron is produced a year, the item can save a cost of over RMB 12 million a year alone.

In 2009, Ling led his disciples at the foundry plant in creating unique skills such as once-off pouring, and cultivated a great number of skill masters. Ling, aged nearly 60, will continue to work hard towards the goal of a rejection rate of 1% together with fellow foundry technicians at Yuchai.

(Source: Guangxi Workers Daily, Hu Weibo, Huang Wenjuan, Zhu Xiaojie)