Apparatus and method for actuating or maintaining a seal by differential pressure

摘要

An apparatus that facilitates tight sealing between a first space and a second space. The second space is at least partially enclosed by a member. The apparatus includes or performs creating or maintaining a pressure difference between a pressure in a third space at a seal assembly and pressure in each of the first space and the second space; and pushing, caused by the pressure difference, against a seal in the seal assembly to tighten sealing provided by the seal.