Numerous references (i.e. API 521) on the subject of maximum velocities in flare headers recommend not to exceed 0.7 Mach. The only reasons given appear to be noise and vibration. I am evaluating an existing system that under maximum conditions will have velocities exceeding .7 Mach. To correct this condition means replacing a considerable amount of buried 20" pipe at a cost of $mm.
My questions are: what is the basis of API 521 recommendation .7 Mach and what are the consequences of exceeding this recommendation during emergency flaring conditions? In order to make an engineering decision to exceed API recommendations I need some sound references.
My questions are: what is the basis of API 521 recommendation .7 Mach and what are the consequences of exceeding this recommendation during emergency flaring conditions? In order to make an engineering decision to exceed API recommendations I need some sound references.
