Gear Pump Seal Performance Analysis Incorporating Non-Linear Gasket Behavior

Abstract

Introduction: Gasket is a key sealing structure in industrial equipment, and its performance and reliability are increasingly required in modern industry. High performance gaskets have complex nonlinear behavior, and new numerical tools need to be developed to simulate their characteristics. This paper takes gear oil pump as the research object, analyzes the nonlinear behavior of gear oil pump gasket, reveals its loading and unloading characteristics, and provides a theoretical basis for the design of sealing elements. This research is helpful to deepen the understanding of gasket sealing mechanism and improve sealing performance and reliability.
Objectives: By studying the sealing performance and developing a new numerical calculation method, the sealing performance of gaskets can be accurately predicted and its nonlinear behavior can be fully considered.
Methods: Numerical simulation and finite element analysis were carried out on the research object. This article uses rubber based composite gaskets and incorporates their loading unloading curves into the numerical model to improve computational efficiency and convergence. The pump body, pump cover, and bolts adopt hexahedral and tetrahedral grids respectively, while the gasket adopts a single-layer grid. The boundary conditions include fixed constraints, bolt pre tightening force applied step by step, and internal pressure. The post-processing stage mainly analyzes the deformation, stress distribution, contact surface details of each component, as well as the closure and pressure characteristics of the gasket.
Results: Under the action of preloading force alone, the deformation of gasket is concentrated around the bolt hole. At the same time, when the internal pressure is applied, the total deformation of gasket is significantly increased, and the central area is obviously thickened. The normal pressure is higher when only the preload force is applied, and the minimum value is located outside the central region. When the internal pressure is applied at the same time, the normal pressure decreases significantly and the minimum position moves to the inside of the center. The distribution trend of total closure was the same in both cases, and the value decreased slightly.
Conclusions: Using a gear oil pump as a representative case, this study examines the non-linear behavior of seals. In particular, it investigates the mechanisms by which two key factors - bolt preload and internal pressure load - affect the sealing performance of these seals. The results show that the gaskets exhibit highly non-linear loading and unloading behavior.