Why is the rectangular rounded corrugated expansion joint rounded

Most of the rectangular rounded corrugated expansion joints are full-height or half-height wave in the DD2000 standard. According to the "CE" standard and general products and combined with the special conditions of my country's power plants, the new power plant flue duct flexible pipes are developed. This product is a power plant, Metallurgical, cement and petrochemical equipment systems are an important part of the operation of large cross-sectional area flue gas medium transportation pipelines. Compared with similar single oblique angles, double oblique angles, bellows angles, and low wave tangent points in geometric nonlinear deformation caused by temperature and load The working characteristics and quality of the small rounded products are actually the same as those of the rectangular direct corrugation, that is, the wave height and wave distance are different, and the same corrugation compensation amount will be different. The deformation of the rounded corners is stable and the internal stress is reduced, which is suitable for hot air and flue gas pipes.

        The corners of the rectangular rounded corrugated expansion joint are formed by a large arc transition to form a rectangular section. The stress level of the corner section is reduced, the dead corner of deformation and the uniform deformation of the product during online operation are eliminated, thus reducing the risk of regional high stress damage and prolonging the time. Product life. The rectangular rounded corrugated expansion joint reduces the thrust of the piping system under the condition that the whole is not unstable and the basic working stiffness is maintained, which improves the thermal compensation ability of the product and reduces the input cost of flexible parts in pipeline construction. Due to the adaptable change of geometry, this product can work reliably in a benign force system under the action of external tensile stress, compressive stress and alternating stress, avoiding the local stress risk area, and in the atmosphere containing H2SO, CO, H2 flue gas When working in the middle, the deterioration trend of stress corrosion cracking (SEE) and corrosion fatigue fracture (CFF) is effectively improved, and the allowable number of thermal cycles of the product is increased without affecting the service life. When the pipe is welded, the welding seam can be far away from the arc tangent point. When the length of one side of the rectangle is less than 2M, the welding seam can be reduced by one, and the amount of welding seam misalignment is greatly reduced. The length error is extremely small, the corrugation is formed, and the stretch-bending forming is plump and smooth. It conforms to the theoretical criterion of good maximum fatigue life of bellows. The arc steel plate at the corner of the rectangular rounded corrugated expansion joint is welded and reinforced, and the interface is made of channel steel, which enhances the structural strength of the product and stretches as a whole.