Research on the hydroformed metal stator bushing based on full restraint at both ends. (October 2021) - Shi, Changshuai
Highlights: We propose an external hydroformed metal stator bushing. Experiments with external hydroformed metal stator bushings were done. The cause of wrinkling of metal stator bushings has been studied. The adaptability of mold size and tube inner diameter is studied. Abstract: The rubber bushing of the positive displacement motor is easy to age, and the metal bushing stator is proposed. We designed and carried out an experiment of hydroforming of metal stator bushing with equal wall thickness. After the experiment, we found that the metal stator bushing was wrinkled. We applied the finite element method to study the cause of wrinkles in the metal stator bushing. The research results show that the main reason why the metal stator bushing is wrinkled is that the inner diameter of the tube blank is larger. Therefore, We use the finite element method to study the influence of the inner diameter of the tube blank on the quality of the metal stator bushing. From the research results, we found that the suitable inner diameter of the tube blank is 86.5 mm. The surface of the metal stator bushing is smooth, the inner surface of the metal stator bushing is close to the mold, and the maximum gap is 0.15 mm. The metal stator bushing formed by tube blank III has a larger minimum wall thickness, a smaller maximum wall thickness, and the smallest wall thickness variance, which is 2.6 mm, 3.22 mm, and 0.028, respectively. The smallest plastic strain, the largest plastic strain, and the largest displacement of the metal stator bushing formed from the tube blank III are 0.2, 0.7, and 14 mm, respectively. When L2/L1 = 0.9577, the quality of the metal stator bushing is better.