Patent ID: 7641450

Claim:
A transfer method for an easily polymerizable substance in which said easily polymerizable substance is transferred using feed pumps that are respectively disposed at a plurality of passages that branch off at the easily polymerizable substance inflow side and converge at an easily polymerizable substance outflow side, wherein the feed pumps are provided with check valves disposed downstream thereof and before the passages converge at the easily polymerizable substance outflow side, the method comprising: stopping at least one of the feed pumps; and while the at least one of the feed pumps is stopped, feeding a portion of the easily polymerizable substance to the at least one stopped feed pump and to the passage disposed thereat in a direction that is opposite to the direction of flow of the easily polymerizable substance provided while the at least one feed pump is activated so that the portion of the easily polymerizable substance passes from a hole in a respective check valve through an outlet of the at least one stopped pump through the pump to an inlet of the at least one stopped pump.