Performance Lubricants
MIL-PRF-27617 Greases—Grease, Aircraft and Instrument,
Fuel- and Oxidizer-Resistant

Product Information
Krytox™ aerospace oils and greases are based on
perfluoropolyether (PFPE) oils. These synthetic fluorinatedlubricants are used in extreme conditions, such ascontinuous high temperatures up to 316 °C (600 °F)
and higher temperatures for shorter periods, depending
on product grade limits. Chemically inert and safe foruse around hazardous chemicals, these lubricants arenonflammable and are safe for use in oxygen service.
Krytox™ oils and greases are silicone free and do notdamage plastics or elastomers, nor cause corrosion
to metals. They are commonly used as lubricants inaerospace, automotive, industrial, and semiconductor
applications, as well as solving many other routine
lubrication problems.
Krytox greases are the original products that this military
specification was written for and have been certified
continuously since the specification was originally written.
™

This is the latest data from the recertification that isrequired every five years. Krytox™ greases are standard asNLGI Grade 2 penetration. If Krytox™ 240 AZ is ordered tomeet MIL-SPEC requirements, it must be ordered as NLGIGrade 1 to meet the specification.

Typical Applications
Applications for Krytox™ lubricants are generally of a
critical nature with temperatures in all industries reachingextremes for conventional lubricants. They are expected
to be durable in the most aggressive environments and are
now often considered an integral part of the design. Where
failure of components is not an option, whether becauseof durability, warranty, safety, loss of productivity, or downtime, Krytox™ is the lubricant of choice in a wide range ofindustries and applications.

In the aerospace industry, Krytox™ oils and greases areapplied on various settings, spanning from bearings andsealants to O-rings and oxygen systems. Krytox™ is avaluable asset to the aerospace industry, due to its superior
performance in a wide range of temperatures scaling from–73 to 316 ºC (–100 to 600 ºF). In addition, it is robust in
harsh environments and has excellent frictional properties,
allowing it to resist change in properties over time, provide
longer wear, and lower energy consumption. Krytox™ lubricantsare compatible with all metals, elastomers, plastics, paints, andfinishes. Due to the intense and severe circumstance of theaerospace industry, it can be expected that Krytox™ delivers ahigh level of product excellence.
Krytox™ 240 AC, 240 AB, and 240 AZ Grade 1 greases now
have NSF approval for incidental food contact (H-1) in andaround food processing areas.

Preparation Before Packing Bearings With Grease
New bearings and equipment that are not lubricated often
have rust preventive oils in them to prevent damage while they
are in storage before use. New bearings should be inspected
for damage and cleanliness before use. The greases orpreservative oils need to be removed when using Krytox™ as alubricant. Failure to do so could result in reduced bearing life.
Bearing life tests on uncleaned bearings have shown reduced
life in high temperature, high speed tests, where the bearing
was filled with a minimum amount of grease. The preservatives
coat the metal surface to prevent rusting, so they can also
prevent the grease from adhering, causing them to be thrown
off by the action of the bearing. They also will oxidize andharden, and can create debris that will contaminate the grease.

Storage and Shelf Life
Krytox™ grease and oil lubricants have an indefinite shelf life, if
unopened and stored in a clean dry location.

Performance Lubricants

Krytox™

CAGE No.: 7GFT8SIC Code: 2992 Lubricating Oils and Greases

NAICS Code: 324191 Lubricating Oils and Greases Manufacturing

DUNS: 079950093
Krytox™ GradeProperty

240 AZ

240 AB

240 ACFPG 028

Qualification Reference Number

AFPET/PTPT 18-007

AFPET/PTPT 18-008

AFPET/PTPT 18-009

AFPET/PTPT 12-003

Grease Type/MIL-PRF-27617 Specified
Operating Range, °C (°F)

Type I/–54 to 149(–65 to 300)

Type II/–40 to 204(–40 to 400)

Type III/–34 to 288(–30 to 400)

Type IV/-73 to 204(–100 to 400)

Krytox™ Useful Range, °C (°F)

–57 to 149 (–71 to 300) –40 to 232 (–40 to 450) –34 to 288 (–29 to 550) ≤69 to 204 (–92 to 399)

NATO Number

G-397

G-398

G-399

G-1350Penetration GradeNLGI 1NLGI 2NLGI 2NLGI 2

Change in Worked Penetration (30 max.)+13+3–3+1Corrosion on Copper (2b max.)

1b1b1b1bHigh Temperature Bearing Performance(500 hr min. at 10,000 RPM, 204 °C [399 °F])—

Stopped at 1,320 hr

Stopped at 1,685 hr

1,691 hr

Evaporation, ASTM D 2595
(22 hr at 204 °C [399 °F]), %

12.9

10.1

0.2

6.61

Oil Separation (30 hr, 204 °C [399 °F]), wt%

—

14.2

15.5

14.25

Solubility in Fuel (20% max.), %—

0.3

0.1

0.1

Liquid Oxygen Impact Sensitivity
20 impacts at 43.3 in, no reaction

No Reaction

No Reaction

No Reaction

No Reaction

Low Temperature Torque, g-cm
at –73 °C (–99 °F) (max.) ASTM D1478
Start 2800
Run 800

Start 1524
Run 364

Water Washout Characteristics (20% max.), %—

0.25

—

0.32

Oxidation Stability (5 max.), psi—0.5——Dirt Count75 μ and larger (0 per cc max.)
25 to 74 μ (1000 per cc max.)

0/26

0/0

0/0

0/45

Resistance to Aqueous Solution
Distilled Water
50/50 Distilled Water/Ethanol

Pass
Pass

Pass
Pass

Pass
Pass

Pass
Pass

Film Stability and Corrosion on Steel

Pass

Pass

Pass

Pass

Base Oil Viscosity, 40 °C (104 °F), cSt

22.8

77.824350.5

E595 Test*——Pass—Note: These values are typical properties and not specifications.
*E595 criteria to pass is <1% for Total Mass Loss and <0.1% for Collected Volatile Condensable Material.

The information set forth herein is furnished free of charge and based on technical data that Chemours believes to be reliable. It is intended for use by persons having technical skill, at their own
discretion and risk. The handling precaution information contained herein is given with the understanding that those using it will satisfy themselves that their particular conditions of use present
no health or safety hazards. Because conditions of product use are outside our control, Chemours makes no warranties, express or implied, and assumes no liability in connection with any useof this information. As with any material, evaluation of any compound under end-use conditions prior to specification is essential. Nothing herein is to be taken as a license to operate under or arecommendation to infringe any patents.
NO PART OF THIS MATERIAL MAY BE REPRODUCED, STORED IN A RETRIEVAL SYSTEM OR TRANSMITTED IN ANY FORM OR BY ANY MEANS ELECTRONIC, MECHANICAL, PHOTOCOPYING, RECORDING OR OTHERWISEWITHOUT THE PRIOR WRITTEN PERMISSION OF CHEMOURS.

For product information, industry applications, technical assistance, or global distributor contacts, visit krytox.com or within the U.S. and Canada, call 1-844-773-CHEM/2436 or
outside of the U.S., call 1-302-773-1000.
© 2018 The Chemours Company FC, LLC. Krytox™ and any associated logos are trademarks or copyrights of The Chemours Company FC, LLC. Chemours™ and the Chemours Logo aretrademarks of The Chemours Company.
Replaces: K-20068-3
C-10065 (10/18)