Nuclear Production of Hydrogen, Fourth Information Exchange ...

A METALLIC SEAL FOR HIGH-TEMPERATURE ELECTROLYSIS STACKS
made of nickel-based superalloy X750 to avoid relaxation when the seal is compressed in its groove,
and a specially profiled outer lining made of Fecralloy. Moreover, a stack design is proposed to tighten
the seals at the operating temperature in order to let the stack pieces expand freely. Tightness
qualifications on a specific device and during HTE stack tests are presented. These new metallic seal
results are very encouraging for the future electrolysis stacks. They confirm that despite their stiffness,
metallic steals can be used in stacks. This solution offer real potentials, such as robustness, pressure
sustaining, and dismantling possibilities. Further investigations are realised in the French project ANR/
Pan-H/EMAIL and should be published soon.
Figure 5: Leak measurement for each load level
ba08-042 - leak test at 800°C under 3N/mm
force
leak
load (N/mm)
4
0.02
3.5
3
0.015
2.5
2
0.01
1.5
cooling
1
0.005
0.5
0
0
0 500 1000 1500
time (min)
leak (Nml/min/mm)
Figure 6: Displacement measurement for each load level
ba08-042 - leak test at 800°C under 3N/mm
4
0.8
load (N/mm)
3
2
1
warming
creep
cooling
0.6
0.4
0.2
displacement
(mm)
0
0
0 500 1000 1500
force
time (min)
displacement
136 NUCLEAR PRODUCTION OF HYDROGEN – © OECD/NEA 2010