Abstract: A seal suitable for a driveshaft of a pump for cryogenic media. The seal can operate without extraneous confining gas, runs frictionless and assures a long service life, which was unattainable so far. The seal is designed as a tandem axial face seal. A sliding ring has sliding faces on both sides with spiral-shaped grooves terminating at an outer periphery, and the sliding ring is fixedly mounted on a driveshaft. The sliding faces each is adjoined by a sliding ring. The sliding ring is tightly connected via a metal bellows with the housing cover on the pump side, and the sliding ring via the metal bellows with the housing cover on the motor side. With the tandem axial face seal, the pump process pressure is sealed with respect to atmospheric pressure, and only a small, controlled gas leakage occurs. The process gas remains 100% pure.

Abstract: The device operates with an internal combustion engine (1) and utilizes the combustion heat of the same. In addition to the heat of the cooling water exiting from the engine (1), the exhaust gases are transferred to a water circuit in an exhaust gas heat exchanger (4). The mechanical performance of the engine (1) is, through the direct application of a hydraulic brake (14), almost completely changed into thermal energy, and the heat thus produced is likewise conducted to the water circuit. The water heated is conducted through a vaporizing unit (7), where it brings the cryogenic fluid conducted in a pipe coil (25) or in a pipe assembly to vaporization.