It surprising difficult to find valves that are capable of handling low pressures by high temperatures. In order to pyrolyse material we have to prevent air to enter the pyrolysiscell. The pyrolysiscell has to be airtight but during the pyrolysis process volatile gases are formed, hydrogen and carbon based gasses like evaporating fat. In the first phase when we plan to dehydrate the corpse we must remove the water-vapor and bring fresh air in the cell. During the pyrolysis phase the produced gases are led to an afterburner that burns the hydrogen to water and volatile carbon gasses to CO2. All in all we need three valves that operate temperatures up to 500C and under 2 Bar of pressure.
A central heating valve demolished, a steel ball from a ball bearing as flow director and another problem is solved.