Story #05 · Supports
The support that had been carrying the wrong load for twenty years
A process engineer verbally told a junior designer to change a 4-inch carbon steel line to stainless steel for corrosion concerns. The designer changed the model. No Management of Change. The stainless steel was ordered.
Three months later, the stress engineer picked it up. Stainless steel has different thermal expansion characteristics. The existing supports had been designed for carbon steel. The expansion loads were different, the support spacing needed to change, and two supports were now inadequate.
When you inherit someone else’s assumptions, you inherit their risks. Every existing support was designed for a specific line at specific conditions. Change the line, change the condition, and that support may no longer be adequate. Formal processes exist for a reason — MOC is not bureaucracy, it is the mechanism that ensures the right people review the right changes.
