The Study On Installation Technology For Key Equipment Of Steckel Mill In Nanjing Iron & Steel Co., Ltd

Wide,medium and heavy plate/coil project is the life project for Nanjing Iron and Steel Co.to carry out the structural adjustment and realize enterprise second pioneering effort.The project is a compact production line with international advanced level of its technology and equipment which is the new technology of steckel rolling imported from abroad the first time.The steckel mill is one type of hot strip mill;The name came from the design philosophy:reversing finishing mill housing equipped with two coiler furnaces to replace semi-continuous rolling finishing mill group.Because the rolled pieces are kept its temperature while rolling in the coiler furnace,so the steckel mill can realize the multi-pass reversing rolling which is especially suitable for the special steel difficult to rolling.The characteristics of steckel mill is low investment,small occupation of land and small scale,etc.The author's main work task in this project was the installation and commissioning of the equipments and hydraulic,lubrication pipes of main rolling line from heating furnace to anterior of finishing process.The total weight of equipment(including cranes within the span)is 11200t; the construction period was only 3 months.The steckel mill is the first super sized mill in domestic;The difficulties and characteristics of installation of the complete set rolling line are the traveling crane's lifting capacity in plant is low,the over-weight equipments are plenty,the construction period is limited,the site field is narrow,the installation precision is high.Weight of single chip frame of the steckel mill is 347t,weight of the vertical mill frame is 182t,and weight of flying shear frame is 175t.The owner could not install the large-tonnage crane to save the investment,the lifting method for oversized equipment in domestic and abroad usually use double machine hosting and large crane.But there is no any related information about if the lifting capacity in plant is not meet the requirement and how to arrange the installation working process of the main equipments because of the compact layout of the steckel mill to meet the time schedule.Therefore,the innovative installation technology shall be made with investigation and technical research and combine the practical situations on site.The detailed analysis was made in advance from the aspects of transportation,entering,unloading,hoisting,installation and commissioning of equipment and the new installation technology of key equipment of steckel mill in Nanjing Iron & Steel Company was developed namely hydraulic lifting method,asymmetric lifting,hot charging process,hydraulic nut tensile method which have met the requirement of super sized steckel mill project construction,filled the blank that Baoye Construction Co.in super sized steckel mill construction field and enhanced the core competitiveness of the company.The new installation technology also ensured the project construction schedule,saved the resources,good for environmental protection and created good economy and society benefits.