A u-cup seal consists of two sealing lips which are forced towards walls as the pressure builds up. The major advantage of u-cup seals is that as the fluid pressure increases so does the force on sealing lips, enhancing the sealing capability of the seal.
The model consists of three axisymmetric parts: piston, housing and u-cup. The u-cup sits inside the gland, cut into the piston. This is a challenging problems as it involves multiple nonlinearities: material nonlinearity, geometric nonlinearity and contact between multiple components. As the geometries and loads are axisymmetric, the problem is analyzed using an axisymmetric model.
The analysis of u-cup seal is performed in three steps. In the first step, interference is resolved and in the second step housing is moved downwards. In the third step, a fluid pressure is applied.
Note: This exercise is part of the Solving Non-linear Problems with Abaqus course.