dho...
Chlorine residue in hydrocarbon or synthetic hydrocarbon fluids is a major problem for hydraulic system components and has been studied extensively by DoD.
Suggest searching DTIC
using terms 'chlorine hydraulic fluid' [terms 'fluid' or 'oil' may be used interchangeably].
Might also try searching DTIC using terms 'chlorine phosphate ester hydraulic fluid' if Your system fluid is not hydrocarbon/synthetic-hydrocarbon based.
May also find following SAE docs of interest.
AIR81 Importance of Physical and Chemical Properties of Aircraft Hydraulic Fluids
AIR810 Degradation Limits of Hydrocarbon-Based Hydraulic Fluids, MIL-PRF-5606, MIL-PRF-83282, and MIL-PRF-87257 Used in Hydraulic Test Stands
AIR1363 Aerospace Hydraulic Fluids Physical Properties
AIR4713 Chlorinated Solvent Contamination of MIL-H-5606/MIL-H-83282 Vehicle Hydraulic Systems
AS4059 Aerospace Fluid Power - Contamination Classification for Hydraulic Fluids
ARP5891 Achieving Cleanliness Standards for Aircraft Hydraulic Systems During Manufacture
Regards, Wil Taylor
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