Analysis Of Flange Sealing Structure Of Non-Circular Cross Section

Flange structure was the most widely removable connection form which had been used in petrochemical, natural gas, mechanical power, energy and other industries. However, with the continuous development of industrial technology and the growing process requirement, the non-circular vessel where had applied has been growing, at the same time, it has became some special flange sealing and fastening methods. Currently, the specific analysis and calculation flange structured had not been perfected, the finite element analysis calculations should have been used. In this paper, we have carried out the pressure tank as research object, analyzing and calculating non-circular cross-section of flange structure.1. With the aid of ANSYS finite element software, the rubber o-ring 2-D finite element model has been used to built, both the media pressure and tighting cases, the non-linearity of material, large deformation and contact behavior of rubber ring should have been considered. The distribution of Von Mises stress and contact stress, contact width and maximum contact deformation of sealed structure within rubber ring were also discussed. The numerical simulation of self-compress process of rubber seal ring has improved the rubber o-ring sealing theory. The results showed that, with the increase of seal pressure, the maximum contact stress would has increased, and the maximum contact stress has been always greater than the medium pressure to meet sealing conditions. It had gained a reasonable compression ratio of rubber o-ring as well as given forward a theory base on the calculation of bolt pre-tightening for non-circular cross section flange sealing structure.2, With the help of ANSYS finite element software, the 3-D FEA model of non-circular cross-section bolt flange sealing structure with APDL language argument has been established, in which MPC technology algorithm and the constraint equations was used to connect the coarse and fine element as well as binding contact. It has considered the contact non-linearity between the rubber ring and the groove including nut and plat head. In the bolt pre-tightening condition, it has obtained the stress intensity and the contact pressure distribution on contact surface of rubber o-ring, in which the stress intensity distribution of rubber ring along the circumferential has been discussed to gain the impact of stress distribution, which was bolt distribution and non-circular connection stiffness of the structure. In the operating conditions, it has effectively analyzed the stress distribution and deformation of the structure of non-circular cross-section flange connected components system from the overall points, at the the time, stress intensity on the components should have been assessed. It has put forward the intensity check criteria in view of the non-circular structure. It also should evaluated the intensity stress path assessment of the thickness and circumferential direction with flat, flange and cylinder structure, fingding that the circumferential stress distribution was related with the structural stiffness.