Braycote Micronic 601 EF grease Braycote 601 EF
Perfluoropolyalkyl ether (PFPAE) base oil with -(CF2)O- and -(CF2)2O- ether groups, thickened with polytetrafluoroethylene (PTFE)
Also known as Braycote Micronic 601 EF
Braycote Micronic 601 EF is a perfluoropolyether (PFPE) grease of NLGI grade 2 with a PTFE thickener, made by Castrol Industrial.
Evidence level
2 of 5
Lab-measured
- 0Predicted only. No one has made it, or no measurement exists.
- 1Calculated. Only calculated or predicted values from sources.
- 2Lab-measured. Measured properties with their conditions stated.
- 3Space-relevant tests. Measured in conditions relevant to space, such as vacuum or atomic oxygen.
- 4Ground-qualified. Qualified for an application on the ground.
- 5Flown or field-proven. Flight or field results exist.
Temperature range
-80 °C to 204 °C
Low-temperature torque
0.057 N/m at -62 °C
Vacuum stability
0.39 % wt total mass loss
Oil separation
10.53 % wt
Recipe, share of the weight
- PFPAE not statedPerfluoropolyalkyl ether base oil
- PTFE not statedPolytetrafluoroethylene
- not statedRust and corrosion inhibitor
Best for
Sealed mechanisms, bearings and O-ring assembly that must run in a hostile chemical environment or in vacuum. Castrol says the grease is designed to operate in the presence of rocket fuels, oxidizers and high vacuum.
Weakest at
Oil separation over time (10.53 % wt after 30 h at 100 °C) and reaction risk on newly exposed aluminum, magnesium and titanium rubbing surfaces, which Castrol says should be evaluated before use.
Risk at a glance
- People Low. Irritant, not classified as hazardous
- If it fails Moderate. Fretting, micropitting and discoloration of grease in long-running Shuttle actuators
- Corrosion Moderate. After 19 years in sealed Shuttle actuators, the Braycote 601 grease was stable and no iron fluoride corrosion was found, but the metal parts showed fretting and micropitting.
Quick facts: Braycote 601 EF
| Property | Value | Basis |
|---|---|---|
| Density | 1.85 to 1.94 g/cm³ | 2 sourced values across conditions |
| Thermal conductivity | 0.15 to 0.21 W/(m·K) | 2 sourced values across conditions |
| Maximum service temperature | 200 to 204 °C | 2 sourced values across conditions |
What is the density of Braycote Micronic 601 EF grease?
Braycote Micronic 601 EF grease has a density of 1.85 to 1.94 g/cm³. The range covers 2 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.
What is the thermal conductivity of Braycote Micronic 601 EF grease?
Braycote Micronic 601 EF grease has a thermal conductivity of 0.15 to 0.21 W/(m·K). The range covers 2 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.
What is the maximum service temperature of Braycote Micronic 601 EF grease?
Braycote Micronic 601 EF grease has a maximum service temperature of 200 to 204 °C. The range covers 2 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.
What is Braycote Micronic 601 EF grease used for?
Uses recorded in the sources include Space Shuttle body flap and rudder speed brake actuators; Clam-shell drive shafts of LDEF experiment A0187-1; Silicone elastomer seals for docking and habitat systems (ground tests).
Why it exists
Braycote Micronic 601 EF is a perfluoropolyether grease used where a lubricant must resist chemicals and vacuum, and where it must not evaporate. Castrol says it is designed to operate in the presence of rocket fuels, oxidizers and high vacuum, and that it is frequently used in space applications including the Space Shuttle and satellites. The grease has an NLGI grade of 2 and a useful temperature range of -80 °C to 204 °C on the datasheet. The flight evidence in this profile is for its parent grease, Braycote 601, which NASA reports lubricated Space Shuttle actuators.
Where it's used
Space Shuttle actuators
NASA reports that the Shuttle body flap and rudder speed brake actuators were lubricated with Braycote 601 and designed to operate for 10 years and 100 flights without relubrication. The rudder speed brake actuators on Discovery reached 19 years of continuous use before inspection.
LDEF experiment drive shafts
Castrol Braycote 601 lubricated the drive shafts of experiment A0187-1 on LDEF. On recovery, the flown grease showed no chemical degradation in Castrol's analysis, although it had picked up a black colour.
Silicone seals for docking and habitat systems (ground tests)
NASA Glenn tested the 601 EF grease on silicone seals. It reduced seal-on-seal unit adhesion from 26.8 psi to 8.75 psi, and atomic oxygen pre-treatment plus grease reduced it to 2.74 psi.
Recipe
Perfluoropolyalkyl ether (PFPAE) base oil with -(CF2)O- and -(CF2)2O- ether groups, thickened with polytetrafluoroethylene (PTFE)
Braycote Micronic 601 EF is a grease made from a perfluoropolyalkyl ether (PFPAE) base oil thickened with fine polytetrafluoroethylene (PTFE) particles, with a rust and corrosion inhibitor. The base oil is a low-molecular-weight polymer with an average molecular weight of 9400 amu, per the NASA report on the parent grease Braycote 601.
| Ingredient | Share of the weight | What it does |
|---|---|---|
| Perfluoropolyalkyl ether base oil PFPAE | not stated | The lubricating fluid. It is chemically inert, has very low vapour pressure and keeps working from -80 °C to 204 °C. |
| Polytetrafluoroethylene PTFE | not stated | The thickener that holds the base oil in a grease structure. |
| Rust and corrosion inhibitor | not stated | Protects steel surfaces. The NASA report and the SPI listing name sodium nitrite for the grease. The Castrol datasheet names only a rust and corrosion inhibitor. |
Weight shares are as printed in the sources.
What it can do
Temperature range
-80 °C to 204 °C
measured
The Castrol datasheet gives a useful temperature range of -80 °C to 204 °C. The NASA report gives an upper limit of 200 C for the parent grease, so the two values are kept side by side.
Low-temperature torque
0.057 N/m at -62 °C
measured
The starting torque at -62 °C is 0.057 N/m by ASTM D1478, as printed on the Castrol datasheet.
Vacuum stability
0.39 % wt total mass loss
measured
After 24 hours at 125 °C and 10^-6 torr, the grease lost 0.39 % wt in total and 0.03 % wt of collected volatile condensable material, by ASTM E595 and NASA SP-R-0022A, as printed on the SPI listing.
Oil separation
10.53 % wt
measured
After 30 hours at 100 °C, the grease separated 10.53 % wt of oil, by ASTM D6184. Over long service, NASA recommends replenishing light-duty grease every 5 years or less.
How it compares
This profile does not compare the grease with a hydrocarbon grease, because no hydrocarbon grease data page was read in this run. Within its own data, the base oil's kinematic viscosity falls from 10855 mm2/s at -54 °C to 45 mm2/s at 99 °C, with a viscosity index of 350. The 0.39 % wt total mass loss in the vacuum test and the 208 °C dropping point are the two figures to read alongside the temperature range.
The same measurements for each material, so you can compare them. Each row names the key condition under the value; the full conditions and methods are in the numbered notes under Technical details.
| Measurement | Braycote 601 EF |
|---|---|
| Thermal behavior and safety | |
| Evaporation loss, data sheet methodASTM D2595, as printed on the product data sheet | 0.87 % wt |
| Evaporation loss, SPI listing method | 0.52 % wt10 |
| Thermal conductivity at -35 °C | 0.15 W/m K21 |
| Thermal conductivity at 75 °C | 0.21 W/m K22 |
| Mass loss expected below this temperature in storage | 190 °C25 |
| Physical and electrical | |
| Density of finished grease at 15 °C | 1.94 g/ml1 |
| Density of grease from the safety data sheet | 1850 kg/m32 |
| Base oil density at 15 °C | 1849 kg/m320 |
| Temperature behavior | |
| Starting torque at -62 °CASTM D1478, as printed on the product data sheet | 0.057 N/m |
| Other measurements | |
| Lower end of useful temperature range | -80 °C3 |
| Upper end of useful temperature range | 204 °C4 |
| Upper operating temperature, NASA description of Braycote 601 | 200 °C5 |
| Dropping pointASTM D2265, as printed on the product data sheet | 208 °C |
| Unworked penetration | 288 0.1 mm6 |
| Worked penetration | 290 0.1 mm7 |
| Oil separation | 10.53 % wt8 |
| Four-ball weld load | 800 kgf9 |
| Total mass loss, vacuum stability | 0.39 % wt11 |
| Collected volatile condensable material, vacuum stability | 0.03 % wt12 |
| Base oil vapour pressure at 20 °C | 4×10^-13 torr13 |
| Base oil vapour pressure at 100 °C | 3×10^-9 torr14 |
| Viscosity index of base oil | 350 -15 |
| Pour point of base oil | -72 °C16 |
| Base oil kinematic viscosity at 38 °C | 148 mm2/s17 |
| Base oil kinematic viscosity at 99 °C | 45 mm2/s18 |
| Base oil kinematic viscosity at -54 °C | 10860 mm2/s19 |
| Oil content of unused grease | 70.7 percent23 |
| Average molecular weight of base oil | 9400 amu24 |
Why choose it, and why not
Good for
- Sealed mechanisms in vacuum or in hostile chemicals. Castrol says it is designed for rocket fuels, oxidizers and high vacuum, and NASA reports it lubricated Shuttle actuators for 19 years.
- Long-life sealed use. The Shuttle grease was stable after 19 years of continuous use in sealed actuators, according to NASA.
Watch out for
- Newly exposed aluminum, magnesium or titanium rubbing surfaces may react with it, so Castrol says such systems must be evaluated.
- Oil separates from the thickener over time. NASA says grease that has lost about 50 percent of its oil is generally no longer effective.
- Its flight heritage is for the parent grease Braycote 601. No flight data for the EF version were found.
Braycote Micronic 601 EF is a well-documented, chemically inert perfluoropolyether grease with strong evidence of long sealed life in Shuttle hardware. The EF version's space heritage is not established in the sources read, so it should be checked against the parent grease data before flight use.
Technical details
For scientists and researchers. Everything above comes from the record below: every number with its method, its conditions and its source.
Other names and standards
The same grade under other systems, as datasheets and standards print them. Each code was checked against the page it comes from.
| System | Codes |
|---|---|
| Trade name | Braycote Micronic 601 EF |
Notes
The method, full conditions and any caveat for the numbered rows above.
| # | Measurement | Method | Conditions | Caveat |
|---|---|---|---|---|
| 1 | Density of finished grease at 15 °C | In-house test by Castrol; no ASTM method is printed for this row | temperature 15 °C / 59 °F | — |
| 2 | Density of grease from the safety data sheet | Printed in the SDS as 1850 kg/m3 (1.85 g/cm3) at 15.6°C; no test method printed | temperature 15.6 °C | — |
| 3 | Lower end of useful temperature range | Stated range on the product data sheet; no test method printed | basis useful temperature range as printed on the product data sheet | — |
| 4 | Upper end of useful temperature range | Stated range on the product data sheet; no test method printed | basis useful temperature range as printed on the product data sheet | — |
| 5 | Upper operating temperature, NASA description of Braycote 601 | Operating range stated in the NASA report; no test method printed | grade Braycote 601 (parent grease, not the EF version) | — |
| 6 | Unworked penetration | ISO 2137 / IP 50, as printed on the product data sheet | sample unworked grease | — |
| 7 | Worked penetration | ISO 2137 / ASTM D217, as printed on the product data sheet | sample after 60 strokes at 25 °C / 77 °F | — |
| 8 | Oil separation | ASTM D6184 / FTM 321.2, as printed on the product data sheet | time temperature 30 h at 100 °C / 212 °F | — |
| 9 | Four-ball weld load | ISO 11008 / ASTM D2596, as printed on the product data sheet | note printed as 800+, so 800 is a lower bound | — |
| 10 | Evaporation loss, SPI listing method | ASTM E595, as printed on the SPI listing; this conflicts with the data sheet, which prints ASTM D2595 and 0.87 % wt | time temperature 30 h at 204 °C / 399 °F | — |
| 11 | Total mass loss, vacuum stability | ASTM E595 / NASA SP-R-0022A; the same 0.39 value is printed on the Castrol data sheet | test ASTM E595 / NASA SP-R-0022Atime temperature 24 h at 125 °C (257 °F)pressure 10^-6 torr | — |
| 12 | Collected volatile condensable material, vacuum stability | ASTM E595 / NASA SP-R-0022A, as printed on the SPI listing | test ASTM E595 / NASA SP-R-0022Atime temperature 24 h at 125 °C (257 °F)pressure 10^-6 torr | — |
| 13 | Base oil vapour pressure at 20 °C | Printed on the SPI listing; no test method printed | temperature 20 °Cfluid base oil | — |
| 14 | Base oil vapour pressure at 100 °C | Printed on the SPI listing; no test method printed | temperature 100 °Cfluid base oil | — |
| 15 | Viscosity index of base oil | ISO 2909 / ASTM D2270, as printed on the product data sheet | fluid base oil | — |
| 16 | Pour point of base oil | ISO 3016 / ASTM D97, as printed on the product data sheet | fluid base oil | — |
| 17 | Base oil kinematic viscosity at 38 °C | ISO 3104 / ASTM D445, as printed on the product data sheet | temperature 38 °C / 100 °Ffluid base oil | — |
| 18 | Base oil kinematic viscosity at 99 °C | ISO 3104 / ASTM D445, as printed on the product data sheet | temperature 99 °C / 210 °Ffluid base oil | — |
| 19 | Base oil kinematic viscosity at -54 °C | ISO 3104 / ASTM D445, as printed on the product data sheet (printed as 10,855) | temperature -54 °C / -65 °Ffluid base oil | — |
| 20 | Base oil density at 15 °C | ASTM D4052 / DIN 51757D, as printed on the product data sheet | temperature 15 °C / 59 °Ffluid base oil | — |
| 21 | Thermal conductivity at -35 °C | Printed on the SPI listing; no test method printed | temperature -35 °C | — |
| 22 | Thermal conductivity at 75 °C | Printed on the SPI listing; no test method printed | temperature 75 °C | — |
| 23 | Oil content of unused grease | Gravimetric analysis, as reported in the NASA report text | sample unused grease samples, gravimetric analysis (Braycote 601) | — |
| 24 | Average molecular weight of base oil | Stated in the NASA report; no test method printed | fluid PFPAE base oil of Braycote 601 | — |
| 25 | Mass loss expected below this temperature in storage | Thermogravimetric analysis and thermodynamic analysis, as summarised in the NASA bulletin (a prediction, not a measured onset) | basis thermogravimetric analysis and thermodynamic bound, Braycote 601 | — |
Corrosion and compatibility
What happens when it meets other materials and environments.
| Environment | Concern | What happens |
|---|---|---|
| Steel gears and bearings of Space Shuttle actuators, after 19 years of sealed use | moderate | After 19 years in sealed Shuttle actuators, the Braycote 601 grease was stable and no iron fluoride corrosion was found, but the metal parts showed fretting and micropitting.1 |
| Controlled static storage of AISI 9310 gear and housing material, for 17 years | low | NASA's bulletin predicts no significant corrosive effect from 17 years of controlled storage.2 |
| Long-term oil separation in service and storage | moderate | The oil separates from the thickener over time, and NASA recommends replenishing light-duty grease every 5 years or less.3 |
| Low Earth orbit on the LDEF trailing edge, shielded from UV and minimal atomic oxygen | low | The grease flown on LDEF showed no measurable chemical degradation, although it picked up a black colour of unidentified contamination.4 |
| # | Environment | Details | Test conditions |
|---|---|---|---|
| 1 | Steel gears and bearings of Space Shuttle actuators, after 19 years of sealed use | The NASA report found no significant chemical difference between the used grease and new grease, and no corrosive effect in the form of iron fluoride. Fretting, micropitting, wear and corrosion of the bearings and gears were still observed, and the grey colour was attributed to metallic iron. | exposure sealed rudder speed brake actuators, 19 years of continuous usegrease Braycote 601 (parent grease)analysis gravimetry, ICP, FTIR and size exclusion chromatography |
| 2 | Controlled static storage of AISI 9310 gear and housing material, for 17 years | Thermogravimetric and thermodynamic analysis predicted no significant corrosive effect from static, controlled storage for 17 years. The bulletin notes that Lewis acids could form from grease and steel and that no significant mass loss should occur below 190ºC without tribological action. | exposure static storage without tribological actionmaterial AISI 9310 steel housing and gearsbasis literature review, WAM testing and thermogravimetric analysis |
| 3 | Long-term oil separation in service and storage | The NASA report explains that oil separates from the thickener with time, and that grease with about 50 percent of its liquid lost is generally no longer effective. Within the sealed Shuttle actuators, base oil separation was not significant after 19 years. | exposure service and storage, sealed and unsealedbasis NASA recommendation and sealed-actuator analysis |
| 4 | Low Earth orbit on the LDEF trailing edge, shielded from UV and minimal atomic oxygen | Castrol's analysis of the flight sample found no degradation of the base oil or thickener. Differential infrared analysis showed the flown grease to be virtually identical to new grease, and its thermogravimetric results were very similar to a control sample. The lubricant had picked up a black colour, not yet identified. | exposure LDEF tray A3 trailing edge, drive shafts of experiment A0187-1, minimal UV and atomic oxygengrease Castrol Braycote 601 (parent grease, not the EF version) |
Risks and side effects
Hazards to people, what happens when a cell overheats, and how the material is handled and stored.
For people
Castrol's safety data sheet gives the grease as an irritant at worst and lists no hazardous ingredients above regulated thresholds.
- The grease
- The SDS gives the emergency overview as CAUTION, with respiratory, eye and skin irritation. It lists no occupational exposure limits.
- Handling
- Use adequate ventilation, safety glasses with side shields or chemical goggles, and suitable protective clothing.
In a fire
The SDS warns that heating can burst the container and that the grease decomposes into hazardous products.
- Decomposition
- The SDS lists hydrogen fluoride and carbonyl difluoride as hazardous decomposition products in a fire.
- Firefighting
- Firefighters should wear self-contained breathing apparatus operated in positive pressure mode.
Handling and storage
The grease is stable in storage, and the SDS lists the materials to keep it away from.
- Storage
- Store in a dry, cool, well-ventilated area away from direct sunlight, with the container tightly closed until use.
- Incompatibility
- The SDS lists alkali metals, halogenated compounds, and strong alkali or Lewis acids at high temperature as incompatible.
Test details
The original wording and numbers from the sources, for readers who want them.
Failure risks
| Failure | Trigger and consequence |
|---|---|
| Fretting, micropitting and discoloration of grease in long-running Shuttle actuatorsmoderate severity | Continuous use for about 19 years in sealed rudder speed brake actuators with AISI 9310 gears and AISI 52100 bearingsGears and bearings showed fretting, micropitting, wear and corrosion, and the grease turned grey and red. NASA concluded the grease was still fit for purpose, but the Discovery actuators were replaced before its return to flight. |
| Oil separation from the thickener during long servicemoderate severity | Time in service; NASA notes that the grease becomes dead when about 50 percent of its oil is lostGrease that has lost about 50 percent of its oil is generally no longer effective, so NASA recommends replenishing light-duty grease no less often than every 5 years. |
| Reaction with Lewis acids or with newly exposed light metal surfacesmoderate severity | Contact with Lewis acid catalysts such as aluminium chloride at elevated temperature, or with newly exposed aluminum, magnesium or titanium rubbing surfacesCastrol says the product may be adversely affected by Lewis acid catalysts at elevated temperature and that new rubbing surfaces of those alloys may react, so such systems should be evaluated thoroughly. |
Side effects on surrounding parts
| Affects | Effect |
|---|---|
| Firefighters and the surrounding area | In a fire the SDS lists hydrogen fluoride and carbonyl difluoride as hazardous decomposition products, and the container may burst when heated. |
Handling and storage
- Store the grease in a dry, cool, well-ventilated area away from direct sunlight, with the container kept tightly closed and sealed until use.
- Use adequate ventilation, safety glasses with side shields or chemical goggles, and suitable protective clothing, as the SDS recommends.
- Clean surfaces of organic rust inhibitors before applying the grease. Castrol names Fluoroclean X100 or Fluoroclean HE to remove it.
Mitigations
- Evaluate aluminum, magnesium and titanium systems thoroughly before use, because the grease may react with newly exposed surfaces of these alloys.
Supply and geography
How common the raw materials are and where they come from.
Braycote Micronic 601 EF grease
Not applicable; the grease is a manufactured lubricant, and no feedstock share was read in this run. Manufacturer per the datasheet (2012): Castrol Industrial, Technology Centre, Whitchurch Hill, Pangbourne, Reading, RG8 7QR, United Kingdom. US supplier per the SDS (2011): Castrol Industrial North America, Naperville, Illinois. No share of supply is printed in either source.
- Recycling
- Not found in any source we hold.
Documents
Datasheets, safety data sheets, papers and standards you can open.
Full record
The complete spore, as stored. Free to reuse under CC-BY-4.0. Images keep the licence shown with each one.
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spore: profile
id: braycote-601ef
spore_version: 0.2
family: perfluoropolyether-greases
name: Braycote Micronic 601 EF grease
abbreviation: Braycote 601 EF
role: High-vacuum, rocket-propellant-compatible lubricating grease (NLGI grade 2) for bearings, gears, actuators and O-ring assembly
category: tribology
type: greases
summary: |
Braycote Micronic 601 EF is a perfluoropolyether (PFPE) grease of NLGI grade 2 with a PTFE thickener, made by Castrol Industrial. Its product data sheet gives a useful temperature range of -80 °C to 204 °C and a dropping point of 208 °C (ASTM D2265). NASA reports that its parent grease, Braycote 601, lubricated Space Shuttle actuators and was stable after 19 years in the sealed actuators. The flight evidence is for Braycote 601, not for the EF version, and no flight data for 601 EF were found.
best_for: Sealed mechanisms, bearings and O-ring assembly that must run in a hostile chemical environment or in vacuum. Castrol says the grease is designed to operate in the presence of rocket fuels, oxidizers and high vacuum.
weakest_at: Oil separation over time (10.53 % wt after 30 h at 100 °C) and reaction risk on newly exposed aluminum, magnesium and titanium rubbing surfaces, which Castrol says should be evaluated before use.
identity:
formula: Perfluoropolyalkyl ether (PFPAE) base oil with -(CF2)O- and -(CF2)2O- ether groups, thickened with polytetrafluoroethylene (PTFE)
source: nasa-tm-2009-215605
where: Lubricant section, which describes the base oil and PTFE thickener; Castrol datasheet, Description section, which names a perfluorinated polyether base oil
designations:
- system: Trade name
code: Braycote Micronic 601 EF
source: castrol-601ef-datasheet
where: Title block, page 1
tags:
environments:
- low-earth-orbit
stresses:
- vacuum-and-outgassing
- atomic-oxygen
- extreme-cold
applications:
- mechanisms
- habitats-and-suits
properties:
- benchmark: density
label: Density of finished grease at 15 °C
value: 1.94
unit: g/ml
scope: material
conditions:
temperature: 15 °C / 59 °F
method: In-house test by Castrol; no ASTM method is printed for this row
status: ground
source: castrol-601ef-datasheet
where: Typical Characteristics table, row Density of finished grease @ 15°C / 59°F, g/ml column
- benchmark: density
label: Density of grease from the safety data sheet
value: 1850
unit: kg/m3
scope: material
conditions:
temperature: 15.6 °C
method: Printed in the SDS as 1850 kg/m3 (1.85 g/cm3) at 15.6°C; no test method printed
status: ground
source: castrol-601ef-sds
where: Section 9, Physical and chemical properties, Density row
- benchmark: min_service_temp
label: Lower end of useful temperature range
value: -80
unit: °C
scope: material
conditions:
basis: useful temperature range as printed on the product data sheet
method: Stated range on the product data sheet; no test method printed
status: ground
source: castrol-601ef-datasheet
where: Product description and Temperature Range line (-80ºC to 204ºC)
- benchmark: max_service_temp
label: Upper end of useful temperature range
value: 204
unit: °C
scope: material
conditions:
basis: useful temperature range as printed on the product data sheet
method: Stated range on the product data sheet; no test method printed
status: ground
source: castrol-601ef-datasheet
where: Product description and Temperature Range line (-80ºC to 204ºC)
- benchmark: max_service_temp
label: Upper operating temperature, NASA description of Braycote 601
value: 200
unit: C
scope: material
conditions:
grade: Braycote 601 (parent grease, not the EF version)
method: Operating range stated in the NASA report; no test method printed
status: ground
source: nasa-tm-2009-215605
where: Lubricant section, operating temperature range (–80 to 200 C)
- benchmark: dropping_point
label: Dropping point
value: 208
unit: °C
scope: material
conditions:
test: ASTM D2265 as printed
method: ASTM D2265, as printed on the product data sheet
status: ground
source: castrol-601ef-datasheet
where: Typical Characteristics table, Dropping point row (208/407 °C/°F)
- benchmark: unworked_penetration
label: Unworked penetration
value: 288
unit: 0.1 mm
scope: material
conditions:
sample: unworked grease
method: ISO 2137 / IP 50, as printed on the product data sheet
status: ground
source: castrol-601ef-datasheet
where: Typical Characteristics table, Unworked Penetration row
- benchmark: worked_penetration
label: Worked penetration
value: 290
unit: 0.1 mm
scope: material
conditions:
sample: after 60 strokes at 25 °C / 77 °F
method: ISO 2137 / ASTM D217, as printed on the product data sheet
status: ground
source: castrol-601ef-datasheet
where: Typical Characteristics table, Worked Penetration row
- benchmark: oil_separation
label: Oil separation
value: 10.53
unit: '% wt'
scope: material
conditions:
time_temperature: 30 h at 100 °C / 212 °F
method: ASTM D6184 / FTM 321.2, as printed on the product data sheet
status: ground
source: castrol-601ef-datasheet
where: Typical Characteristics table, Oil Separation row
- benchmark: four_ball_weld_load
label: Four-ball weld load
value: 800
unit: kgf
scope: material
conditions:
note: printed as 800+, so 800 is a lower bound
method: ISO 11008 / ASTM D2596, as printed on the product data sheet
status: ground
source: castrol-601ef-datasheet
where: Typical Characteristics table, Four Ball Weld Load row (Weld Point, 800+ kgf)
- benchmark: evaporation_loss
label: Evaporation loss, data sheet method
value: 0.87
unit: '% wt'
scope: material
conditions:
time_temperature: 22 h at 204 °C / 400 °F
method: ASTM D2595, as printed on the product data sheet
status: ground
source: castrol-601ef-datasheet
where: Typical Characteristics table, Evaporation Loss row
- benchmark: evaporation_loss
label: Evaporation loss, SPI listing method
value: 0.52
unit: '% wt'
scope: material
conditions:
time_temperature: 30 h at 204 °C / 399 °F
method: ASTM E595, as printed on the SPI listing; this conflicts with the data sheet, which prints ASTM D2595 and 0.87 % wt
status: ground
source: spi-z05086
where: Evaporation weight loss line of the product description
- benchmark: total_mass_loss
label: Total mass loss, vacuum stability
value: 0.39
unit: '% wt'
scope: material
conditions:
test: ASTM E595 / NASA SP-R-0022A
time_temperature: 24 h at 125 °C (257 °F)
pressure: 10^-6 torr
method: ASTM E595 / NASA SP-R-0022A; the same 0.39 value is printed on the Castrol data sheet
status: ground
source: spi-z05116
where: Vacuum Stability Test section
- benchmark: volatile_condensable_material
label: Collected volatile condensable material, vacuum stability
value: 0.03
unit: '% wt'
scope: material
conditions:
test: ASTM E595 / NASA SP-R-0022A
time_temperature: 24 h at 125 °C (257 °F)
pressure: 10^-6 torr
method: ASTM E595 / NASA SP-R-0022A, as printed on the SPI listing
status: ground
source: spi-z05116
where: Vacuum Stability Test section, VCM value
- benchmark: vapour_pressure
label: Base oil vapour pressure at 20 °C
value: 4.e-13
unit: torr
scope: material
conditions:
temperature: 20 °C
fluid: base oil
method: Printed on the SPI listing; no test method printed
status: ground
source: spi-z05086
where: Base Oil Vapor Pressure (torr) list, 20°C row
- benchmark: vapour_pressure
label: Base oil vapour pressure at 100 °C
value: 3.e-9
unit: torr
scope: material
conditions:
temperature: 100 °C
fluid: base oil
method: Printed on the SPI listing; no test method printed
status: ground
source: spi-z05086
where: Base Oil Vapor Pressure (torr) list, 100°C row
- benchmark: viscosity_index
label: Viscosity index of base oil
value: 350
unit: '-'
scope: material
conditions:
fluid: base oil
method: ISO 2909 / ASTM D2270, as printed on the product data sheet
status: ground
source: castrol-601ef-datasheet
where: Typical Characteristics table, Viscosity Index row
- benchmark: pour_point
label: Pour point of base oil
value: -72
unit: °C
scope: material
conditions:
fluid: base oil
method: ISO 3016 / ASTM D97, as printed on the product data sheet
status: ground
source: castrol-601ef-datasheet
where: Typical Characteristics table, Pour Point row (-72/-100 °C/°F)
- benchmark: kinematic_viscosity
label: Base oil kinematic viscosity at 38 °C
value: 148
unit: mm2/s
scope: material
conditions:
temperature: 38 °C / 100 °F
fluid: base oil
method: ISO 3104 / ASTM D445, as printed on the product data sheet
status: ground
source: castrol-601ef-datasheet
where: Typical Characteristics table, Base Oil Viscosity @ 38°C row
- benchmark: kinematic_viscosity
label: Base oil kinematic viscosity at 99 °C
value: 45
unit: mm2/s
scope: material
conditions:
temperature: 99 °C / 210 °F
fluid: base oil
method: ISO 3104 / ASTM D445, as printed on the product data sheet
status: ground
source: castrol-601ef-datasheet
where: Typical Characteristics table, Base Oil Viscosity @ 99°C row
- benchmark: kinematic_viscosity
label: Base oil kinematic viscosity at -54 °C
value: 10855
unit: mm2/s
scope: material
conditions:
temperature: '-54 °C / -65 °F'
fluid: base oil
method: ISO 3104 / ASTM D445, as printed on the product data sheet (printed as 10,855)
status: ground
source: castrol-601ef-datasheet
where: Typical Characteristics table, Base Oil Viscosity @ -54°C row
- benchmark: base_oil_density
label: Base oil density at 15 °C
value: 1848.9
unit: kg/m3
scope: material
conditions:
temperature: 15 °C / 59 °F
fluid: base oil
method: ASTM D4052 / DIN 51757D, as printed on the product data sheet
status: ground
source: castrol-601ef-datasheet
where: Typical Characteristics table, Base Oil Density row
- benchmark: low_temperature_starting_torque
label: Starting torque at -62 °C
value: 0.057
unit: N/m
scope: material
conditions:
temperature: '-62 °C / -80 °F'
condition: starting torque
method: ASTM D1478, as printed on the product data sheet
status: ground
source: castrol-601ef-datasheet
where: Typical Characteristics table, Low temperature Torque starting row at -62°C
- benchmark: thermal_conductivity
label: Thermal conductivity at -35 °C
value: 0.15
unit: W/m K
scope: material
conditions:
temperature: '-35 °C'
method: Printed on the SPI listing; no test method printed
status: ground
source: spi-z05086
where: Thermal Conductivity line, -35° C row
- benchmark: thermal_conductivity
label: Thermal conductivity at 75 °C
value: 0.21
unit: W/m K
scope: material
conditions:
temperature: 75 °C
method: Printed on the SPI listing; no test method printed
status: ground
source: spi-z05086
where: Thermal Conductivity line, 75° C row
- benchmark: oil_content
label: Oil content of unused grease
value: 70.7
value_high: 77.3
unit: percent
scope: material
conditions:
sample: unused grease samples, gravimetric analysis (Braycote 601)
method: Gravimetric analysis, as reported in the NASA report text
status: ground
source: nasa-tm-2009-215605
where: Gravimetric Analysis section, text on Table 1
- benchmark: average_molecular_weight
label: Average molecular weight of base oil
value: 9400
unit: amu
scope: material
conditions:
fluid: PFPAE base oil of Braycote 601
method: Stated in the NASA report; no test method printed
status: ground
source: nasa-tm-2009-215605
where: Lubricant section, base oil paragraph
- benchmark: onset_of_mass_loss
label: Mass loss expected below this temperature in storage
value: 190
unit: °C
scope: material
conditions:
basis: thermogravimetric analysis and thermodynamic bound, Braycote 601
method: Thermogravimetric analysis and thermodynamic analysis, as summarised in the NASA bulletin (a prediction, not a measured onset)
status: calculated
source: nesc-tb-07-01
where: Data and Analysis section, Issue 2 results, sentence about no significant mass loss below 190ºC
risks:
hazards:
- text: Castrol's safety data sheet (version 2, dated 03/03/2011) gives the emergency overview as CAUTION and says the product may cause respiratory tract, eye and skin irritation.
ghs: []
source: castrol-601ef-sds
where: Sections 2 and 3
- text: The same SDS states that the product does not contain any hazardous ingredients at or above regulated thresholds and assigns no occupational exposure limits.
ghs: []
source: castrol-601ef-sds
where: Sections 3 and 8
failure_risks:
- mode: Fretting, micropitting and discoloration of grease in long-running Shuttle actuators
trigger: Continuous use for about 19 years in sealed rudder speed brake actuators with AISI 9310 gears and AISI 52100 bearings
consequence: Gears and bearings showed fretting, micropitting, wear and corrosion, and the grease turned grey and red. NASA concluded the grease was still fit for purpose, but the Discovery actuators were replaced before its return to flight.
severity: moderate
source: nasa-tm-2009-215605
where: Abstract and Introduction
- mode: Oil separation from the thickener during long service
trigger: Time in service; NASA notes that the grease becomes dead when about 50 percent of its oil is lost
consequence: Grease that has lost about 50 percent of its oil is generally no longer effective, so NASA recommends replenishing light-duty grease no less often than every 5 years.
severity: moderate
source: nasa-tm-2009-215605
where: Introduction, paragraph on relubrication
- mode: Reaction with Lewis acids or with newly exposed light metal surfaces
trigger: Contact with Lewis acid catalysts such as aluminium chloride at elevated temperature, or with newly exposed aluminum, magnesium or titanium rubbing surfaces
consequence: Castrol says the product may be adversely affected by Lewis acid catalysts at elevated temperature and that new rubbing surfaces of those alloys may react, so such systems should be evaluated thoroughly.
severity: moderate
source: castrol-601ef-datasheet
where: Conditions of Use, Limitations
side_effects:
- text: In a fire the SDS lists hydrogen fluoride and carbonyl difluoride as hazardous decomposition products, and the container may burst when heated.
affects: Firefighters and the surrounding area
source: castrol-601ef-sds
where: Sections 5 and 10
handling:
- text: Store the grease in a dry, cool, well-ventilated area away from direct sunlight, with the container kept tightly closed and sealed until use.
source: castrol-601ef-sds
where: Section 7
- text: Use adequate ventilation, safety glasses with side shields or chemical goggles, and suitable protective clothing, as the SDS recommends.
source: castrol-601ef-sds
where: Section 8
- text: Clean surfaces of organic rust inhibitors before applying the grease. Castrol names Fluoroclean X100 or Fluoroclean HE to remove it.
source: castrol-601ef-datasheet
where: Description and Conditions of Use
mitigations:
- text: Evaluate aluminum, magnesium and titanium systems thoroughly before use, because the grease may react with newly exposed surfaces of these alloys.
source: castrol-601ef-datasheet
where: Conditions of Use, Limitations
corrosion:
- environment: Steel gears and bearings of Space Shuttle actuators, after 19 years of sealed use
headline: After 19 years in sealed Shuttle actuators, the Braycote 601 grease was stable and no iron fluoride corrosion was found, but the metal parts showed fretting and micropitting.
effect: The NASA report found no significant chemical difference between the used grease and new grease, and no corrosive effect in the form of iron fluoride. Fretting, micropitting, wear and corrosion of the bearings and gears were still observed, and the grey colour was attributed to metallic iron.
rating: moderate
conditions:
exposure: sealed rudder speed brake actuators, 19 years of continuous use
grease: Braycote 601 (parent grease)
analysis: gravimetry, ICP, FTIR and size exclusion chromatography
source: nasa-tm-2009-215605
where: Abstract and Summary of Results, points 1 to 4
- environment: Controlled static storage of AISI 9310 gear and housing material, for 17 years
headline: NASA's bulletin predicts no significant corrosive effect from 17 years of controlled storage.
effect: Thermogravimetric and thermodynamic analysis predicted no significant corrosive effect from static, controlled storage for 17 years. The bulletin notes that Lewis acids could form from grease and steel and that no significant mass loss should occur below 190ºC without tribological action.
rating: low
conditions:
exposure: static storage without tribological action
material: AISI 9310 steel housing and gears
basis: literature review, WAM testing and thermogravimetric analysis
source: nesc-tb-07-01
where: Data and Analysis section, Issue 2 results
- environment: Long-term oil separation in service and storage
headline: The oil separates from the thickener over time, and NASA recommends replenishing light-duty grease every 5 years or less.
effect: The NASA report explains that oil separates from the thickener with time, and that grease with about 50 percent of its liquid lost is generally no longer effective. Within the sealed Shuttle actuators, base oil separation was not significant after 19 years.
rating: moderate
conditions:
exposure: service and storage, sealed and unsealed
basis: NASA recommendation and sealed-actuator analysis
source: nasa-tm-2009-215605
where: Introduction, relubrication paragraph; Summary of Results, point 3
- environment: Low Earth orbit on the LDEF trailing edge, shielded from UV and minimal atomic oxygen
headline: The grease flown on LDEF showed no measurable chemical degradation, although it picked up a black colour of unidentified contamination.
effect: Castrol's analysis of the flight sample found no degradation of the base oil or thickener. Differential infrared analysis showed the flown grease to be virtually identical to new grease, and its thermogravimetric results were very similar to a control sample. The lubricant had picked up a black colour, not yet identified.
rating: low
conditions:
exposure: LDEF tray A3 trailing edge, drive shafts of experiment A0187-1, minimal UV and atomic oxygen
grease: Castrol Braycote 601 (parent grease, not the EF version)
source: ldef-n93-2
where: Experiment A0187-1 (Chemistry of Micrometeoroids), page 1043
uses:
- application: mechanisms
device: Space Shuttle body flap and rudder speed brake actuators
example: NASA reports that the actuators were lubricated with Braycote 601 and designed to operate for 10 years and 100 flights without periodic relubrication. Some actuators had been in continuous use for over twenty years without inspection, and the rudder speed brake actuators on Discovery had been in continuous use for 19 years.
source: nasa-tm-2009-215605
where: Abstract and Introduction
- application: mechanisms
device: Clam-shell drive shafts of LDEF experiment A0187-1
example: Castrol Braycote 601 lubricated the four drive shafts that opened and closed the canisters of experiment A0187-1 on LDEF, which saw minimal direct UV and minimal atomic oxygen.
source: ldef-n93-2
where: Experiment A0187-1, page 1043
- application: habitats-and-suits
device: Silicone elastomer seals for docking and habitat systems (ground tests)
example: NASA Glenn coated Parker S0383-70 silicone seals with Braycote Micronic 601 EF. The grease reduced seal-on-seal unit adhesion from 26.8 psi to 8.75 psi, and atomic oxygen pre-treatment plus grease reduced it to 2.74 psi.
source: degroh-2011
where: Section 4, Conclusions
supply:
- subject: Braycote Micronic 601 EF grease
abundance: 'Not applicable; the grease is a manufactured lubricant, and no feedstock share was read in this run. Manufacturer per the datasheet (2012): Castrol Industrial, Technology Centre, Whitchurch Hill, Pangbourne, Reading, RG8 7QR, United Kingdom. US supplier per the SDS (2011): Castrol Industrial North America, Naperville, Illinois. No share of supply is printed in either source.'
producers: []
critical_lists: []
recycling: Not found in any source we hold.
substitutes: []
source: castrol-601ef-datasheet
where: Datasheet, last page (address) and Description; SDS Section 1 (supplier address)
documents:
- title: Castrol Braycote Micronic 601 EF, product data sheet (09 Oct 2012), hosted by SPI Supplies
type: datasheet
url: https://www.2spi.com/catalog/documents/Braycote%20Micronic%20601%20EF.pdf
year: 2012
- title: Braycote 601 EF material safety data sheet, Castrol Industrial North America, MSDS 451695, version 2, hosted by SPI Supplies
type: sds
url: https://www.2spi.com/catalog/documents/sds-05086-Braycote601EF.pdf
year: 2011
- title: 'Performance and Analysis of Perfluoropolyalkyl Ether Grease Used on Space Shuttle Actuators: A Case Study (NASA/TM-2009-215605/REV1)'
type: report
url: https://ntrs.nasa.gov/api/citations/20090022125/downloads/20090022125.pdf
year: 2013
- title: NASA Engineering and Safety Center Technical Bulletin No. 07-01, Braycote Grease retains tribological properties for 17 years in controlled storage
type: report
url: https://ntrs.nasa.gov/api/citations/20240000670/downloads/TB%2007%2001%20Braycote%20Grease%20Storage.pdf
year: 2007
- title: Evaluation of Seals, Lubricants, and Adhesives Used on LDEF (Boeing, NASA LDEF results)
type: report
url: https://ntrs.nasa.gov/api/citations/19930019086/downloads/19930019086.pdf
year: 1993
- title: Effects of Atomic Oxygen and Grease on Outgassing and Adhesion of Silicone Elastomers for Space Applications (de Groh, Puleo, Steinetz)
type: paper
url: https://ntrs.nasa.gov/api/citations/20110014982/downloads/20110014982.pdf
year: 2011
gaps:
- No flight or space-exposure data for the Braycote Micronic 601 EF version were found. The flight evidence (Space Shuttle actuators, LDEF drive shafts) is for Braycote 601, the parent grease. The EF version is described as reformulated under more environmentally friendly manufacturing conditions (SPI listing), so its heritage is not established.
- The Castrol datasheet (09 Oct 2012) and SDS (version 2, 03/03/2011) were read as hosted copies on SPI Supplies. Castrol's current versions were not read, and the SDS may have been superseded.
- 'The two sources disagree on the evaporation loss: 0.87 % wt after 22 h at 204 °C (ASTM D2595, datasheet) against 0.52 % wt after 30 h at 204 °C (ASTM E595, SPI listing). Both are kept with their methods.'
- 'The two sources disagree on the upper operating temperature: 204 °C (datasheet) against 200 C (NASA report, for Braycote 601). Both are kept.'
- The corrosion inhibitor is named differently by the sources. The NASA report and the SPI listing name sodium nitrite for Braycote 601 or 601 EF; the Castrol datasheet names only a rust and corrosion inhibitor. The inhibitor is not verified for the EF version.
- Flash point is printed as Not available in the SDS, so no value is given. The SDS prints no occupational exposure limit.
- The CAS number for Braycote 601 EF is not printed in any source read. The SDS uses the supplier's MSDS number 451695.
- Mass-loss numbers for the grease itself (TML and CVCM from the 2011 Glenn paper) were not extracted as values. The paper states that greased S0383-70 remained below NASA's TML of 1 % and CVCM of 0.1 %, which is a limit and not a measured value of the grease.
- Several properties use names not in spores/property-canon.yaml (unworked and worked penetration, oil separation, four-ball weld load, evaporation loss, total mass loss, volatile condensable material, base oil density, low-temperature starting torque, oil content, onset of mass loss). They are snake_case names used as printed.
- No production share, country-level supply or critical-mineral listing was found for the grease, its PFPE base oil or its PTFE thickener. The fluorine and PTFE feedstock chain was not read.
- No atomic oxygen erosion yield or radiation result for the grease itself was found in the sources read.
sources:
castrol-601ef-datasheet:
title: Castrol Braycote Micronic 601 EF, Grease, Rust Preventive, Rocket Propellant Compatible (Product Data)
id: Castrol Industrial product data sheet dated 09 Oct 2012, hosted by SPI Supplies
url: https://www.2spi.com/catalog/documents/Braycote%20Micronic%20601%20EF.pdf
year: 2012
kind: datasheet
license: Castrol product data sheet, cited and not reproduced
castrol-601ef-sds:
title: Material Safety Data Sheet, Braycote 601 EF (Castrol Industrial North America, Inc.)
id: MSDS 451695, product code 451695-US03, version 2, date of issue 03/03/2011, hosted by SPI Supplies
url: https://www.2spi.com/catalog/documents/sds-05086-Braycote601EF.pdf
year: 2011
kind: datasheet
license: Supplier safety data sheet, cited and not reproduced
spi-z05116:
title: Braycote Micronic 601EF High Vacuum Grease, SPI Supplies listing (item Z05116)
id: SPI Supplies item Z05116, page read 2026-11-01
url: https://www.2spi.com/item/z05116/
year: 2026
kind: web
license: Distributor listing, cited
spi-z05086:
title: Braycote 601EF High Vacuum Grease, SPI Supplies listing (item Z05086)
id: SPI Supplies item Z05086, page read 2026-11-01
url: https://www.2spi.com/item/Z05086
year: 2026
kind: web
license: Distributor listing, cited
nasa-tm-2009-215605:
title: 'Performance and Analysis of Perfluoropolyalkyl Ether Grease Used on Space Shuttle Actuators: A Case Study (Morales, Street, Zaretsky)'
id: NASA/TM-2009-215605/REV1, December 2013; NTRS 20090022125
url: https://ntrs.nasa.gov/api/citations/20090022125/downloads/20090022125.pdf
year: 2013
kind: report
license: public domain (NASA)
nesc-tb-07-01:
title: 'NASA Engineering and Safety Center Technical Bulletin No. 07-01: Braycote Grease retains tribological properties for 17 years in controlled storage'
id: NESC TB 07-01; NTRS 20240000670
url: https://ntrs.nasa.gov/api/citations/20240000670/downloads/TB%2007%2001%20Braycote%20Grease%20Storage.pdf
year: 2007
kind: report
license: public domain (NASA)
ldef-n93-2:
title: Evaluation of Seals, Lubricants, and Adhesives Used on LDEF (Duerch, Keough, Pippin, Boeing Defense and Space Group)
id: NASA LDEF results; NTRS 19930019086, page 1043
url: https://ntrs.nasa.gov/api/citations/19930019086/downloads/19930019086.pdf
year: 1993
kind: report
license: public domain (NASA)
degroh-2011:
title: Effects of Atomic Oxygen and Grease on Outgassing and Adhesion of Silicone Elastomers for Space Applications (de Groh, Puleo, Steinetz)
id: NASA Glenn Research Center paper; NTRS 20110014982
url: https://ntrs.nasa.gov/api/citations/20110014982/downloads/20110014982.pdf
year: 2011
kind: paper
license: public domain (NASA)
license: CC-BY-4.0
updated: '2026-11-01'
review:
status: draft
method: assistant
checked_values: 28
unreachable: 0
caveats: 3
note: 'Read by an AI assistant on 2026-11-01: values copied from the 2012 Castrol datasheet, the 2011 SDS, two SPI listings and three NASA documents read in this run. Two conflicts between sources are kept side by side.'
story:
recipe:
line: Braycote Micronic 601 EF is a grease made from a perfluoropolyalkyl ether (PFPAE) base oil thickened with fine polytetrafluoroethylene (PTFE) particles, with a rust and corrosion inhibitor. The base oil is a low-molecular-weight polymer with an average molecular weight of 9400 amu, per the NASA report on the parent grease Braycote 601.
parts:
- name: Perfluoropolyalkyl ether base oil
symbol: PFPAE
share: 70.7 to 77.3 percent of the unused grease by weight (NASA report, gravimetric analysis)
role: The lubricating fluid. It is chemically inert, has very low vapour pressure and keeps working from -80 °C to 204 °C.
- name: Polytetrafluoroethylene
symbol: PTFE
share: the balance of the grease; the exact share is not printed and varies from lot to lot
role: The thickener that holds the base oil in a grease structure.
- name: Rust and corrosion inhibitor
share: not printed
role: Protects steel surfaces. The NASA report and the SPI listing name sodium nitrite for the grease. The Castrol datasheet names only a rust and corrosion inhibitor.
risk_groups:
- title: For people
level: 1
verdict: Irritant, not classified as hazardous
lead: Castrol's safety data sheet gives the grease as an irritant at worst and lists no hazardous ingredients above regulated thresholds.
points:
- label: The grease
line: The SDS gives the emergency overview as CAUTION, with respiratory, eye and skin irritation. It lists no occupational exposure limits.
- label: Handling
line: Use adequate ventilation, safety glasses with side shields or chemical goggles, and suitable protective clothing.
- title: In a fire
level: 2
verdict: Decomposition products include hydrogen fluoride
lead: The SDS warns that heating can burst the container and that the grease decomposes into hazardous products.
points:
- label: Decomposition
line: The SDS lists hydrogen fluoride and carbonyl difluoride as hazardous decomposition products in a fire.
- label: Firefighting
line: Firefighters should wear self-contained breathing apparatus operated in positive pressure mode.
- title: Handling and storage
level: 0
verdict: Keep sealed, dry and away from incompatible materials
lead: The grease is stable in storage, and the SDS lists the materials to keep it away from.
points:
- label: Storage
line: Store in a dry, cool, well-ventilated area away from direct sunlight, with the container tightly closed until use.
- label: Incompatibility
line: The SDS lists alkali metals, halogenated compounds, and strong alkali or Lewis acids at high temperature as incompatible.
why: Braycote Micronic 601 EF is a perfluoropolyether grease used where a lubricant must resist chemicals and vacuum, and where it must not evaporate. Castrol says it is designed to operate in the presence of rocket fuels, oxidizers and high vacuum, and that it is frequently used in space applications including the Space Shuttle and satellites. The grease has an NLGI grade of 2 and a useful temperature range of -80 °C to 204 °C on the datasheet. The flight evidence in this profile is for its parent grease, Braycote 601, which NASA reports lubricated Space Shuttle actuators.
uses:
- where: Space Shuttle actuators
line: NASA reports that the Shuttle body flap and rudder speed brake actuators were lubricated with Braycote 601 and designed to operate for 10 years and 100 flights without relubrication. The rudder speed brake actuators on Discovery reached 19 years of continuous use before inspection.
- where: LDEF experiment drive shafts
line: Castrol Braycote 601 lubricated the drive shafts of experiment A0187-1 on LDEF. On recovery, the flown grease showed no chemical degradation in Castrol's analysis, although it had picked up a black colour.
- where: Silicone seals for docking and habitat systems (ground tests)
line: NASA Glenn tested the 601 EF grease on silicone seals. It reduced seal-on-seal unit adhesion from 26.8 psi to 8.75 psi, and atomic oxygen pre-treatment plus grease reduced it to 2.74 psi.
can_do:
- label: Temperature range
benchmark: max_service_temp
value: '-80 °C to 204 °C'
line: The Castrol datasheet gives a useful temperature range of -80 °C to 204 °C. The NASA report gives an upper limit of 200 C for the parent grease, so the two values are kept side by side.
- label: Low-temperature torque
benchmark: low_temperature_starting_torque
value: 0.057 N/m at -62 °C
line: The starting torque at -62 °C is 0.057 N/m by ASTM D1478, as printed on the Castrol datasheet.
- label: Vacuum stability
benchmark: total_mass_loss
value: 0.39 % wt total mass loss
line: After 24 hours at 125 °C and 10^-6 torr, the grease lost 0.39 % wt in total and 0.03 % wt of collected volatile condensable material, by ASTM E595 and NASA SP-R-0022A, as printed on the SPI listing.
- label: Oil separation
benchmark: oil_separation
value: 10.53 % wt
line: After 30 hours at 100 °C, the grease separated 10.53 % wt of oil, by ASTM D6184. Over long service, NASA recommends replenishing light-duty grease every 5 years or less.
compare: This profile does not compare the grease with a hydrocarbon grease, because no hydrocarbon grease data page was read in this run. Within its own data, the base oil's kinematic viscosity falls from 10855 mm2/s at -54 °C to 45 mm2/s at 99 °C, with a viscosity index of 350. The 0.39 % wt total mass loss in the vacuum test and the 208 °C dropping point are the two figures to read alongside the temperature range.
compare_rows:
- label: Dropping point
benchmark: dropping_point
- label: Total mass loss in vacuum
benchmark: total_mass_loss
- label: Viscosity index
benchmark: viscosity_index
handling:
- Keep the container tightly sealed and store it in a dry, cool, well-ventilated place, away from alkali metals, halogenated compounds and Lewis acids.
- Wear safety glasses with side shields or chemical goggles, and use adequate ventilation.
- Clean rubbing surfaces of organic rust inhibitors before applying the grease. Castrol names Fluoroclean X100 or Fluoroclean HE for removal.
good_for:
- Sealed mechanisms in vacuum or in hostile chemicals. Castrol says it is designed for rocket fuels, oxidizers and high vacuum, and NASA reports it lubricated Shuttle actuators for 19 years.
- Long-life sealed use. The Shuttle grease was stable after 19 years of continuous use in sealed actuators, according to NASA.
watch_out:
- Newly exposed aluminum, magnesium or titanium rubbing surfaces may react with it, so Castrol says such systems must be evaluated.
- Oil separates from the thickener over time. NASA says grease that has lost about 50 percent of its oil is generally no longer effective.
- Its flight heritage is for the parent grease Braycote 601. No flight data for the EF version were found.
verdict: Braycote Micronic 601 EF is a well-documented, chemically inert perfluoropolyether grease with strong evidence of long sealed life in Shuttle hardware. The EF version's space heritage is not established in the sources read, so it should be checked against the parent grease data before flight use.
References
Every number above carries a reference number. Click one to see the source and where in it the value comes from.
Updated