SEAL WITH EXTENDED SERVICE LIFE.

The seal consists of a shell with the stepped housing and rod with two rubber gaskets (rings with circular or rectangular section), the gaskets being placed between the movable rings and separated by the movable spacer. When assembled, the outer diameter of the rubber gaskets does not exceed the inner diameter of the housing. The spring is intended for loading the rubber gaskets after they have been mounted in the housing. The jacket serves to protect the rubber gaskets from damage and for centering the rod with the gaskets when it is being mounted in the housing. Tests of the seal with rubber gaskets on the basis of SKMS-10 rubber showed that at minus 60 degree C the force for mounting them is one third to one half smaller than the forces of mounting radially compressed rings whose deformation occurs during the process of mounting them in the cavity to be sealed. It is shown that the new design of the seals makes it possible, in sealing joints of dismountable pipes at temperatures below minus 20 degree C, to use chemically stable rubbers, e. g. , those based on fluorocaoutchouc which in most cases have low frost resistance ( minus 10 to minus 20 degree C), nor are lubricants needed.