The design and research institute of NHIstarts the development of 70 mn blade hot-pressing molding press, based on the Highquality water turbine blade projects of SHENYANG RESEARCH INSTITUTE OF FOUNDRY.On the basis of accurate simulation calculation, developers adopts virtualprototype technology, optimization design method, innovation of structure form,optimization of control method, which developed the first domestic large-scalehigh quality blade hot-pressing mold molding press, for those technicaldifficulties such as large size blade, high operating temperature, long moldingtime, large horizontal lateral force, and higher precision control.

For the equipment, the height is 16.3m, theweight is 1100t, the installed power is 2200kw, which formed by beam, movedcross beam, upper beam, stand column, working table, hydraulic system and electriccontrol system and other parts. Developers invented the positioning of thelocking system, which is effectively against 3D yawing force in forming ofblade, to ensure the quality of the blade shape. It adopts load balancetechnology, which improves the load distribution of the compressor, reduces thebeam deflection. Application of strength design ideas and 8 surface orientationtechnology, guarantees the equipment stiffness and accuracy. Using largecomplex box component welding technology, makes the equipment weight reduced by25% ,which reduces cost by 40% and  improves the market competitiveness. Moldchanging efficiency has been increased by 60% through a quick die change system.For the first time, large tonnage press adopts the wheel moving working-table, whichgreatly reduces the wear and tear of working-table; integrates the volumecontrol of variable pump, proportion technology and sensing technology for closed-loopcontrol; leads to high control accuracy, long holding time, greatly improvesthe quality and material utilization for blade. (Zhao Xuping)