The Design of a Test Setup for the Testing and Evaluation of Rotary Shaft Seal Failure

Abstract

An experimental setup was designed and assembled to test the performance of a rotary seal stack under industry conditions. The system is composed of five subsystems: the DUT and drive system, the pressure system, the cooling system, control and data acquisition, and the frame. The setup can hold up to 3 seals pairs that can be arranged in different configurations. The main parameters recorded for the system are the pressure differential, the DUT shaft speed, the torque applied, and the temperature of the working fluid, DUT surface, and DUT interior. It is imperative that each subsystem works together to meet different requirements of the rotary seal test setup.Rotary seals are seals used in machinery with rotating or oscillating motions around a rotating shaft. Rotary seals are widely used in various industries to increase long-term performance and the lifespan of mechanical equipment. The seals are designed to create a barrier around a rotating shaft and their purpose is to withstand high temperatures, hold high flow, and prevent leakage of fluids or lubricants out of machines while also protecting internal components from contaminants such as dust or mud. There are various cross section designs for rotary seals, and they can be made from many different types of materials. The main parameters determining performance and lifespan of the rotary seals are operating speeds and heat production from the seal lip. This setup focuses on being able to evaluate both the effect of operating speeds and heat production on the rotary seals throughout experimental tests. This thesis will explore the design and manufacturing process of the test setup for rotary shaft seals. The goal of the setup was to be able to test the rotary seals at high temperature, hold high flow, and operate at high speeds until failure of the seals. An iterative design process was followed to recreate operation conditions used in industry with the requirements of being able to control the shaft speed, the pressure, and maintain operating temperature. The test setup was able to record data on pressure, operating temperature, speed, flow, leakage rate, and current data to evaluate the performance of multiple differing rotary shaft seals until failure.