In processes for the liquefaction of hydrogen, valves are required to control or stop flow. As part of the IDEALHY project, research has been carried out into valves that are used for cryogenic mass flow, so called cryovalves. The projected increase in liquefaction capacities and system pressures require valve sizes that are not currently available.
In the project, a new valve design has been developed and tested which satisfies the re-quirements of future processes for hydrogen liquefaction and has sufficient capacity for fur-ther improvement in performance.
The new valves are equipped with a compensation function for the forces exerted on the valve spindle by the pressure. The unique feature of the design of the pressure compensa-tion is that the fluid works on the warm end of the valve via a heat exchanger. This means the necessary sealing functions can be achieved considerably more easily.
These sealing functions have been tested for valves up to the maximum size of DN400. The valve concept has also been tested using a prototype under cryogenic conditions and the effectiveness has been proven.
