Relief Valve Sizing
Familiarity with the ASME Section 8 and relevant API publications is recommended.
- The Liquid Relief - known flow calculation has options to size for single or multiple valves or non-certified valves.
- The Gas Relief - known flow calculation has options for Section 1, Section 8 or the Fire Code. The reaction force and the noise level are calculated.
- The Steam Relief - known flow calculation has options for Section 1, Section 8 and the Fire Code and calculates the reaction force and noise level.
- The 2-phase - known flow calculation has options for Section 1, Section 8 and the Fire Code and calculates the reaction force and noise level. It has 7 different 2-phase calculations.
- The Heat Exchanger - entrapped liquid calculation is for a blocked-in liquid filled exchanger which has the heat turned on. It calculates the flow caused by the liquid expansion.
- The Heat Exchanger - Tube failure calculation is for tube rupture where the tube pressure is 50% greater than the shell pressure. It assumes no vaporisation of the shell side product.
- The Pipeline - Entrapped liquid calculation is for liquid expansion in long, blocked in, pipelines on a hot day. It usually only takes a very small relief valve to avoid blowing the gaskets.
- The Fire size - Liquid vaporization is the most complex calculation. It gathers the flame wetted area of up to 15 liquid containing vessels. The heat input is calculated either by The API 520 or the National Fire Protection Association NFPA #30, method and a relieving flow rate is determined. The reaction force and relieving noise level are also calculated.
- The Fire size - Gas expansion also gathers the flame wetted area, this time of up to 15 gas containing vessels. The maximum flow is then back calculated from the valve size. The reaction force and relieving noise level are then calculated.