Abstract: A gas-oil drive for forward and reverse mechanical adjusting movements. Gas, which is available for every direction of movement of an adjusting drive at a pressure greater than atmospheric pressure, conveys its pressure in a pressure tank to control oil which flows to an adjusting device for carrying out a control operation. For both oppositely directed adjusting movements of the gas-oil drive, a single pressure tank for delivering control oil under pressure to the respective corresponding position of the adjusting device, and a single unpressurized container for receiving expelled, unpressurized control oil are provided. The unpressurized container is located above the level of the pressure tank, and a bore on the unpressurized container is connected with a bore on the pressure tank by means of a control oil line in which is located a check valve which closes in a direction of flow toward the unpressurized container.

Abstract: A seal for a drive journal of a ball valve. The elements which directly carry out the sealing action are arranged below a thrust collar which is directed against the cover of the ball valve and is displaceable in the axial direction with the aid of set screws which extend through the cover. The sealing ring is a U-ring which abuts the thrust collar and the walls of the drive journal and the housing. The U-ring is provided with an annular slot which is open toward a thrust ring and, at its deepest portion, has a metallic compensating ring followed by a spiral ring.The present invention relates to a seal for a drive journal of a ball valve, according to which the elements which directly carry out the sealing action are arranged below a thrust collar which is directed against the cover of the ball valve and is displaceable in the axial direction with the aid of set screws which extend through the cover.