Very challenging selection of rupture discs
Thread Content
The company has a storage tank used to hold low-temperature liquids. The temperature in the gas space is around -10°C, and the normal operating pressure is 80–120 kPa. A rupture disc is installed at the top of the tank; its designed diameter is 1”, and its designed burst pressure is 370 kPa. A safety valve is installed at the outlet of the rupture disc. The pipeline between the rupture disc and the safety valve is filled with nitrogen (as required by the process), at a pressure of about 60 kPa. Due to process requirements, it is necessary to remove oxygen from the tank, as well as from the pipelines between the tank, the rupture disc, and the safety valve. The method for doing this involves first creating a vacuum of -40 kPa, then increasing the pressure to 200 kPa, and repeating this process 5 times. What type of rupture disc should be chosen under these conditions? I would appreciate recommendations from experts
First of all, it is necessary to ensure that the rupture disc does not explode during the displacement process as much as possible. Additionally, all pressure difference changes and vacuum requirements must be taken into account during the calculation. 1. Temperature factors are excluded. 2. All pressures are to be considered as gauge pressure. (The poster didn’t specify, so it’s left as is for now.) 3. Under normal operating conditions, the pressure difference is 20–60 KPA; the burst pressure is 310 KPA. 4. During the displacement process: a. Deoxygenation takes place between the tank and the rupture disc. (It is recommended to manually open the safety valve at this point.) Pressure difference: -40 KPA. (If it is not opened, the pressure difference of -100 KPA represents the limit for reverse supply.) Or a bracket may be needed). Deoxygenation can proceed normally, and it can be carried out 5 times in total. b, Deoxidation between the burst disc and the safety valve. (It is recommended to maintain a pressure of 200 KPA inside the tank at this time) to carry out deoxygenation normally. c. Once deoxygenation is complete, please first restore the normal pressure between the rupture disc and the safety valve. Restore the tank again. In summary, it’s actually a matter of the sequence of the deoxygenation processes. The maximum pressure difference that the rupture disc can withstand throughout the process is 240 KPA, while the rupture pressure is 310 KPA; it is sufficient to choose a rupture disc whose overall error is within 80%. Counter-allegation is the first choice. Feel free to reach out to me if you have any questions. I’m willing to communicate with everyone.
The reverse-arch shaped rupture disc is the preferred choice; it can withstand back pressure. If you have any questions, feel free to ask me – I am in the business of selling domestically produced rupture discs