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.

容积式电机橡胶衬套易老化，建议采用金属衬套定子。我们设计并进行了等壁厚金属定子衬套液压成形试验。经过实验，我们发现金属定子衬套起皱了。我们应用有限元方法来研究金属定子衬套中产生皱纹的原因。研究结果表明，金属定子衬套起皱的主要原因是管坯内径较大。因此，我们采用有限元方法来研究管坯内径对金属定子衬套质量的影响。从研究结果中，我们发现管坯的合适内径为86.5 mm。金属定子衬套表面光滑，金属定子衬套内表面紧贴模具，最大间隙为0.15mm。管坯III形成的金属定子衬套最小壁厚较大，最大壁厚较小，壁厚方差最小，分别为2.6 mm、3.22 mm和0.028。由管坯III形成的金属定子衬套的最小塑性应变、最大塑性应变和最大位移分别为0.2、0.7和14mm。当L2/L1=0.9577时，金属定子衬套质量较好。分别。由管坯III形成的金属定子衬套的最小塑性应变、最大塑性应变和最大位移分别为0.2、0.7和14mm。当L2/L1=0.9577时，金属定子衬套质量较好。分别。由管坯III形成的金属定子衬套的最小塑性应变、最大塑性应变和最大位移分别为0.2、0.7和14mm。当L2/L1=0.9577时，金属定子衬套质量较好。