Wide design margins do not improve engineering

摘要

Engineers use design and safety factors in sizing and specifying instrumentation or major process equipment, such as pumps, valves and compressors. Design factors are applied to cover the uncertainty in piping and equipment calculations. Such practices can contribute to "over-design" and can negatively affect performance of the process unit, resulting in higher costs. Several case histories investigate how over-design factors have caused problems in the operations of pumps, heat exchangers and control valves.