Sil computer pump failure probability

The failure probability data for pumps comes mainly from the following sources: 1. Historical operation and maintenance records: By statistically analyzing the frequency and types of failures of pumps in these records, it is possible to determine their failure probability. 2. Data provided by the manufacturer: Equipment manufacturers usually provide the mean time between failures (MTBF) or the mean failure rate (λ) of the equipment, so as to calculate the failure probability. 3. Industry databases: Internationally recognized equipment reliability databases such as OREDA and NERC GADS collect failure data on various types of equipment during actual operation; by querying these databases, it is possible to determine the failure probability. 4. Experimental data: Fault data of the equipment under specific operating conditions are collected through accelerated life testing or long-term durability testing, to further estimate the failure probability. The data obtained through these four methods each have their advantages and disadvantages; it is necessary to take into account various factors such as the actual operating conditions of the equipment and environmental conditions in order to determine a relatively accurate failure probability. .

This post was last edited by sun_fm on 2023-9-15 at 13:57. Pumps and related electrical circuits do not have a SIL rating, so it is impossible to conduct any SIL calculations for them. However, experts believe that pumps can be used as SIL1 devices (for measuring elements such as the operating status of contactors, and actuating elements such as the contacts of relays). For SIL1 devices, no further verification is required; they meet the requirements by default. In any case, as long as it’s not SIL2, it’s fine. Personally, I think this is inappropriate; without a SIL rating, it should not be considered a SIF (except for SIL0 circuits). But we can certainly use the measuring instruments at the outlet, such as pressure transmitters and flow meters, to achieve the required measurement conditions ； The cut-off valve or control valve at the pump outlet can completely be used as an actuator to meet the requirement of stopping the pump (the valve is closed first and then the pump is stopped, which can be achieved via DCS). Furthermore, excessive safety analysis (which is inherently semi-quantitative and semi-qualitative) results in the situation where no protective layer can be used, and only motors can be employed……

Appendix E of AQT3054 contains IE frequency values, but only provides failure probabilities such as those for pump seal failure. Table E.2 does show the selection probabilities for those with mechanical failures. You can also take a look at GBT32857 (it doesn’t cover motors)