Numerical determination of safety valve efficiencies

Based on observed thrust and flow volume profiles as a function of the lift in closure and nozzle assemblies of known geometry, the flow volume can easily be determined for variation in pressure for a safety valve with a geometrically similar closure and nozzle of any size, combined with a spring of any prestress and rigidity. The outflow conditions and the spring capacity are considered, starting with a non-dimensional evaluation in order to generalize the problem. The resulting program permits calculation of the operating characteristics of a safety valve of specific properties under set operating conditions, in only a few minutes, even using a medium capacity computer. (R.H.)