Engineering expert witness Philip J. O’Keefe, PE, writes that pressurized vessels can pose a danger for various reasons.
Perhaps the most obvious source of danger posed by a pressurized vessel is when its contents rapidly and violently discharge. This scenario presents the same hazards mentioned above, coupled with dangers associated with flying objects and shock waves. For example, if a pressure vessel is not securely held in place and it fails, the rapid release of its contents could literally turn it into a missile careening out of control.
I happened to be in close proximity to one of these “unintentional flying objects” one day. The valve broke off an unsecured pressurized gas cylinder of the type that welders use. Its gas escaped with sufficient force to cause the cylinder to fly across a concrete floor and crash through a cinderblock wall. The violent and rapid release of a pressure vessel’s contents also has the potential to create shock waves strong enough to move heavy objects and people, capable of catapulting them through the air.
So it’s obvious then that the release of substances from a failed pressure vessel can lead to serious problems, but are there ways to prevent these failures from happening? Yes, there are. We’ll discuss that subject in my next installment where we will discuss, among other things, “overpressure devices.”