Nowadays, in various industries such as aerospace industry, gas and oil, chemical industry, refineries and petrochemical industries,etc., mechanisms at high high pressure are required to allow the process to be completed. Pressure rise of the fluid occurs inside the chamber which has usually a cylindrical shape. Therefore, it is vital to design a sealing system in order to prevent the leakage of the fluid. The leakage happens when the fluid pressure is increased. The reason for this is that as the process progresses,the pressure differences between the outside and inside of the system goes up and consequently the tendency of the fluid leakage increases in a way that the tank turns into a kind of un controllable vessel chamber that even the least disruption in sealing system causes fluid leakage and it’s damage of which maybe irreparable. Therefore, for such processes (high pressure processes), sealing secure is an extremely important prerquisite. This research aims at designing a high-pressure seal, based on the Bridgman plan, by means of which the fluid pressure is increased through a sealing system, as a result of which the sealing operation is carried out securely. Bridgman has stated that the key development which enabled him to reach higher pressures without leaks was his invention of the unsupported-area seal, now called the Bridgman seal. The principle of its operation is that pressure in the contained fluid produces an “over pressure” in the seal, which prevents leakage. In order to check the sealing system operation, ABAQUS simulation software was used. Different sealing rings (o-ring, u-ring, c-ring and v-ring) were simulated. A sealing ring is acceptable that can create enough sealing pressure which is greater than the fluid pressure. In addition, the shape of the ring should be such that the sealing ring pressure distribution is more uniform to prevent seal damage. The choice of a proper material is probably the most critical factor in the design of seals able to withstand extremely high pressure, and knowledge of material mechanical properties is essential for the finite-element model (FEM) simulations needed to understand and optimize seal behavior. Based on very few commercial solutions proposed for high pressure applications five materials potentially suitable for ultrahigh-pressure sealing systems have been selected for testing. Nitrile-Nutadiene Rubber (NBR), Silicone Rubber, Polyamide 6 (PA6) and Ultrahigh Molecular Weight Polyethylene (UHMWPE) reinforced with glass and ceramic microspheres to enhance wear resistance have been considered suitable to be used in the sealing ring for their good pressure carrying capability combined with wear life. Properties of PA6, UHMWPE-glass and UHMWPE-ceramic obtained from previous research. Uniaxial tension and stress relaxation tests were performed to obtain properties of NBR and silicone rubber. Uniaxial tension tests showed that the behavior of NBR and silicone rubber were hyperelastic, but PA6 and UHMWPE materials exhibited a typical elasto-plastic behavior. Combination of viscoelastic and hyperelastic models were used to simulate the behavior of NBR and silicone rubber, and a combination of elastic and viscoelastic models were used to simulate the behavior of PA6, UHMWPE-glass and UHMWPE-ceramic. Keywords: Sealing, High-Pressure, Bridgman, Polymers, Hyperelastic
