由吉林工学院高技术产品研制厂在引进、消化、吸收国外设备的基础上，重新设计和研制出DYL-4型多功铁密封箱式护生产线，并于94年元月8日起在上海汽车齿轮厂正式运行，主要用于上海桑塔轿钢车变速箱齿轮的热处理加工．四个月来，共生产了100多炉零件（气体碳氮共渗），设备运行 By the introduction of high-tech product development plant in Jilin Institute of Technology, in the introduction, digestion and absorption of foreign equipment, based on the redesign and development of DYL-4-type multi-iron sealed box protection production line, and in January 8, 94 in Shanghai Automobile gear factory official operation, mainly used for Shanghai Santacan steel gearbox gear heat treatment processing. Over the past four months, more than 100 furnace parts (gas carbonitriding) were produced and the plant was operating