(1) During the extrusion process, the temperature of the inner lining of the spiral steel pipe continues to rise as the extrusion process progresses. At the end of the extrusion, the temperature of the inner wall of the lining near the extrusion die is high, reaching 631°C. The temperature of the middle lining and the outer tube does not change much.
(2) In the non-working state, the maximum equivalent stress of the spiral steel pipe is 243MPa, which is mainly concentrated on the inner wall of the spiral pipe. In the preheating state, its maximum value is 286MPa, distributed in the middle part of the inner wall surface of the lining. In the working state, its maximum equivalent stress is 952MPa, which is mainly distributed in the high-temperature area at the upper end of the inner wall. The stress concentration area inside the spiral steel pipe is mainly distributed in the high-temperature area, and its distribution is the same as the temperature distribution. The thermal stress generated by the temperature difference has a greater impact on the internal stress distribution of the spiral steel pipe.
(3) The radial stress of the spiral steel pipe. In the non-working state, the spiral steel pipe is mainly subjected to the prestress provided by the external prestress. The radial direction of the spiral steel pipe is in a compressive stress state, of which the maximum value is 113MPa, distributed on the outer wall of the spiral steel pipe. In the preheating state, the maximum radial pressure is 124MPa, mainly concentrated at the upper and lower-end surfaces. In the working state, the maximum radial pressure is 337MPa, mainly concentrated in the upper part of the spiral steel pipe.
Post time: Sep-26-2024