Everything is inspected and damaged pipes are repaired or replaced. The next turnover for Equistar is in the spring of 2001. When piping is replaced, it is replaced by sections. There are many different shapes and sizes of pipe. Chemical engineers and mechanical engineers look at the pipes and determine why a particular pipe was damaged or in need of repair.
Size plays a major role.
Perhaps the pipe needs to be larger or smaller. Engineers use the formula for volume of a cylinder to determine what size pipe to use, since pipes are in the form of a cylinder, and it's what goes in the cylinder that counts. The engineers are actually determining how much liquid must flow though a particular pipe when they are determining volume of the cylinder represented by the pipe.