Bladder/Bellows Liner
Metal-Bellows or PTFE Bladder for Tank Liner
The tank liner is an 8 kg, chemically inert internal barrier fabricated from 316L stainless steel bellows or an alternative PTFE bladder to contain water within settlement storage vessels. Conventional elastomeric seals degrade under radiation and vacuum exposure, creating severe contamination and leakage risks across extended lunar deployments. By eliminating elastomers, the non-rigid metal or fluoropolymer construction accommodates up to 10,000 thermal expansion cycles with zero operational power consumption. Operating with a 100,000-hour mean time between failures, the vacuum-compatible assembly is rated for a 25-year service lifetime before requiring robotic replacement across a 100-year settlement lifecycle.
Metal bellows or PTFE bladder providing chemically inert, vacuum-stable inner liner for water storage tanks, eliminating elastomer degradation over 100-year mission.
Purpose
Metal bellows or PTFE bladder providing chemically inert, vacuum-stable inner liner for water storage tanks, eliminating elastomer degradation over 100-year mission.
Context
Child of L2-WTR-STOR in L1-WTR water processing chain
Principles
- ▸Metal bellows accommodate thermal expansion without leaks
- ▸PTFE bladder alternative for non-cyclic tanks
- ▸No elastomer to degrade under radiation
- ▸Replaceable as a service item via L1-MNT
- ▸Fatigue-rated for 10,000+ thermal cycles
Typical implementations
- ▸Industrial metal bellows (Servometer, BellowsTech)
- ▸Aerospace metal-lined pressure vessels
- ▸Bellows-sealed valve heritage
Lunar considerations
- ▸Eliminates elastomer degradation (a major long-mission risk)
- ▸Compatible with vacuum-side of tank
- ▸Robotic replacement protocol via L1-MNT
Specifications
Functional
| primary function | Metal bellows or PTFE bladder providing chemically inert, vacuum-stable inner liner for water storage tanks, eliminating elastomer degradation over 100-year mission. |
| thermal cycles | 10000 |
| replacement interval years | 25 |
Physical
| mass kg | 8 |
| materials | 316L SS bellows, PTFE alternative liner |
| vacuum compatibility | True |
Operational
| power consumption w | 0 |
| thermal range c | -40, 70 |
| lifetime years | 25 |
| mtbf hours | 100000 |
Interfaces
Provides
- Inert inner liner
Requires
- Periodic replacement (every 25 years)
Cite this entry
Lunar Ark Codex. "Bladder/Bellows Liner" (L3-WTR-STOR-BLAD). Retrieved 10 September 2026, from https://lunarark.com/entry/L3-WTR-STOR-BLAD
Licensed CC-BY-SA 4.0. You may reuse and adapt this entry with attribution, under the same licence.