Precise modeling of mould core for wavy lip seal

Wavy lip seal is a dynamic pressure seal with excellent sealing performance. However, establishing a precise model of the mould core is extremely difficult because of its irregular cylindrical shape resulting in the technical plight of the wavy lip seal in precision manufacturing and performance analysis. To solve this problem, a new method based on the principle of circumferential unwrapping and wrapping transformation (CUWT) was proposed to build the accurate model of the mould core. The CUWT principle was introduced in detail. Then, the modeling method of a mould core for wavy lip seals was presented. Finally, error analysis and machining experiment were carried out to verify the applicability of the proposed method. The results of the analysis show that the maximum error of the model is less than 10-5 mm. Machining experiment also shows that the method is simple and effective and that it fully meets the high modeling precision requirements for wavy lip seals. The high precision modeling technology lays the foundation for the manufacture and performance analysis of wavy lip seals. In particular, the CUWT principle proposed in this study can also be used to solve the problem of accurate modeling and the Numerical Control (NC) machining of other complex cylindrical parts. The conclusions show that the proposed algorithm not only has high precision, but also has a strong versatility, which can effectively compensate for the defects of the existing Computer Aided Design (CAD) and Computer Aided Manufacturing (CAM) technology in the design and manufacture of complex cylindrical parts.