Safety instrument system is composed of sensor, logic solver and final actuator. It is widely used in process industry, such as oil and gas industry, chemical industry, metallurgy and electric power industry. It is an important measure to ensure the safety of production, which can effectively avoid the potential danger to people, equipment and the environment. However, when it breaks down, the consequences can be expected to be extremely serious. Therefore, HIPPS requires low risk, so it is necessary to quantitatively evaluate the dynamic performance of HIPPS to ensure the high safety of HIPPS during the design life cycle.
In this paper, a Bayesian network based method is proposed to evaluate the dynamic performance of HIPPS. The effects of different detection methods and maintenance methods on the dynamic performance of HIPPS were analyzed quantitatively. The results show that the performance of the system has been improved obviously after maintenance. Compared with the traditional method, the performance of HIPPS is improved by introducing partial stroke test. The sensitivity analysis shows that the failure rate has a great influence on the risk of HIPPS valve. Increased coverage of PST may improve the performance of HIPPS.