Self-Enhancing Processing System
Self-Enhancing Processing System is applied for self-reinforcing and strengthening treatment of pressure-bearing parts such as (ultra) high-pressure vessels, fuel common rail pipes, high-pressure oil pipes, ultra-high pressure reactors, etc., and can perform enhanced sealing and strength testing, with the highest pressure up to 1500MPa, optional fully automatic flexible clamp.
Technical Parameters:
Output pressure level: 600MPa, 1000MPa, 1380MPa, 1500MPa;
Test medium: hydraulic oil; (selected according to pressure)
Working method: primary or secondary boosting.
Generally, increasing the wall thickness of the container can improve the load-bearing capacity of the container to a certain extent. However, for high-pressure and ultra-high-pressure vessels, as the working pressure increases and the wall thickness increases infinitely, the stress distribution on the vessel wall will become more uneven. Moreover, when the working pressure in the container is greater than 0.580s, increasing the wall thickness cannot avoid the yielding of the inner wall. In addition, the increase in wall thickness undoubtedly increases material consumption and processing difficulties. Therefore, an immediate and effective way to improve the elastic bearing capacity of high-pressure and ultra-high-pressure vessels is to prestress the walls.
Self-reinforcement means applying high pressure on the inner wall of the cylinder to cause the inner wall to yield and produce residual deformation that expands in the radial direction, and then the pressure is released. At this time, due to the elastic contraction of the outer layer material, the inner layer material that has been plastically deformed will generate compressive stress after elastic recovery, which is a method to obtain residual compressive stress. When a thick-walled cylinder is subjected to internal pressure load, the inner wall stress is greater than the outer wall stress. When the inner wall yields, the outer layer of the cylinder still has considerable elastic load-bearing capacity. If the inner wall is hydraulically pressed or mechanically pressed before work, the inner layer material yields first and produces residual expansion deformation into an elastoplastic state. After unloading, the inner layer gets compressive prestress and the outer layer gets tensile prestress. When the pressure load is applied again after work, the stress of the inner wall will be reduced, while the stress of the outer wall will increase. The difference in stress between the inner and outer layers will be reduced and the unevenness of the stress distribution will be improved, and the inner wall will yield after being put under pressure again. The pressure is increased. Self-reinforcement cannot increase the bursting pressure of thick-walled cylinders. Since the inner wall obtains residual compressive stress, it can improve the ability of the inner wall material to resist fatigue damage, which is beneficial to improving the fatigue life.
The self-reinforcement process generally uses the outer wall strain as the control variable. Corresponding to each circumferential strain, the degree of plastic deformation of the cylinder can be predicted and the corresponding elastic-plastic interface radius can be determined. The biggest advantage of the self-reinforced container is that after the working internal pressure is applied, the stress on the inner wall with the greatest stress is reduced, the stress distribution becomes uniform, all stresses are maintained within the elastic range, the elastic operating range is expanded, and the elastic load-bearing capacity is improved. Another outstanding advantage of self-reinforced containers is that there is compressive residual stress on the inner wall, which will reduce the average stress on the inner wall and significantly increase the fatigue strength during operation. Self-reinforcement technology has become an important method in the design of ultra-high pressure vessels. As a pressure treatment technology, self-reinforcement can also be used in the manufacture of general pressure vessels. Its purpose is to reduce the thickness of the vessel wall and save materials due to the improvement of elastic load-bearing capacity. Or use lower strength materials instead to reduce product production costs.
