R&d And Finite Element Analysis On Hot Spinning Machine Of Cng Cylinders

The project comes from 325, 425 spinning machine R & D projects proposed by a gas factory in Nanjing.As gas storage vessel, CNG cylinders have been widely used in the industrial, mining, military, medicine, diving cars and other fields. The traditional method to produce CNG cylinders is welding, but with the continuous development of spinning technology, people found that spinning technology is a better way to produce CNG cylinders. It can virtually eliminate the defects such as weld strength reduction, brittle rupture and tensile stress concentration of the traditional welding production, so that air tightness and pressure of the cylinders have been greatly improved, meanwhile it has the advantages such as lower tonnage equipment, lower mould manufacturing cost, wider forming range and higher production quality etc.The 425 and 325 automatic CNG cylinder spinning devices (production line) were developed by the research team. This device can achieve non-core multi-pass shell nosing and back cover after local heating the steel cylinders. It has simple structure, neat appearance, high efficiency, and has improved the level of thermal shut CNG spinning machine at home and abroad, lower the equipment costs, and improved market competitiveness of the production.What the paper studies are as follows:Taking into account realistic, efficiency and accuracy, established finite element simulation model of spinning technology, saluted the material model, boundary conditions, the roller track and other key issues, drew spinning force energy parameters, lay the foundation mechanics for the overall design of the spinning machine.Based on the above force energy parameters, designed the body structure of CNG cylinder hot spinning machine. The spinning machine is made of spindle unit, mould device, stirring device, processing delivery device, heating and feeding device, sub-feed device, blowing the end unit, transfer roller and other components. This paper describes the design of spindle unit and mould device, the kinematics analysis and mechanical calculations for the key components, and the finite element simulation analysis and optimization of the main components. The results show that this spinning device as a whole has meet the structural stiffness and strength, the productions which this device produce have high dimensional accuracy, surface quality, and the device has reached to the international advanced level.