Molykote D-321R Anti-Friction Coating, 9.3 oz

MOLYKOTE D-321 R Product Specifications

Technical values are based on current DuPont MOLYKOTE D-321 R product information and technical data. Consult the current manufacturer documentation for application-specific requirements.

Applications for MOLYKOTE D-321 R

MOLYKOTE D-321 R is designed for metal-to-metal combinations where high loads are combined with slow to medium-fast movement. It is particularly suited to applications where conventional wet lubricants are undesirable or where a dry lubricating film is required.

• Plain bearings, bushings and sleeves
• Slides, guides and tracks
• Power screw drives
• Threaded connections and fasteners
• High-load sliding surfaces
• Chains
• High-voltage switches
• Components requiring boundary lubrication
• Running-in of highly stressed components
• Hard-to-reach surfaces
• Emergency lubrication applications
• Applications involving high vacuum or extreme temperatures

Dry-Film Lubrication with MoS₂ and Graphite

D-321 R combines two solid lubricants—molybdenum disulfide and graphite—in an air-curing coating system. The resulting dry film provides lubrication without leaving a conventional oil or grease film on the component surface.

The dry-film approach is particularly useful for applications where dust, dirt or other contaminants could be attracted by a wet lubricant. DuPont identifies the coating for high-load, low-speed and oscillating applications as well as for intermittent operation.

High-Temperature Dry Lubricant

MOLYKOTE D-321 R has a manufacturer-specified service temperature range of -180°C to 450°C (-292°F to 842°F). This wide temperature range makes the coating suitable for applications where a conventional lubricant may not provide the required temperature performance.

Temperature capability does not by itself establish suitability for a particular aircraft or component. Always verify the applicable maintenance manual, component manufacturer's instructions or other controlling technical documentation before application.

Application Instructions

Proper surface preparation is important for adhesion and service life of the dry-film coating.

1. Clean the surface: Thoroughly clean and degrease the component before applying D-321 R.
2. Prepare the surface when appropriate: DuPont indicates that phosphatization or sandblasting with 180-grit media can improve adhesion and service life.
3. Shake the aerosol: Shake the aerosol can thoroughly before application.
4. Apply evenly: Spray using a sweeping motion to produce a uniform coating.
5. Control film thickness: The recommended dry-film thickness is approximately 5–20 μm.
6. Allow the coating to dry: At 23°C, the coating is touch-dry after approximately 5 minutes. DuPont indicates that drying can be accelerated to approximately 1 minute with hot air at 80°C.

Application conditions, surface preparation and curing requirements should be evaluated for the specific component and operating environment.

MOLYKOTE D-321 R for Aircraft and Aerospace Maintenance

MOLYKOTE D-321 R has documented applications in aerospace-related maintenance. DuPont specifically describes the product as a dry-film lubrication solution for parts and components that cannot be readily disassembled and identifies applications such as engine fan blade root overhaul and maintenance of difficult-to-access components.

The coating is also intended for metal-to-metal applications involving slow to medium-fast movement and high loads, making its characteristics relevant to selected aircraft maintenance applications involving sliding, threaded or highly loaded metal components.

Important: The presence of an aerospace application does not mean D-321 R is approved for every aircraft, engine or component. Use only when permitted by the applicable maintenance documentation or component manufacturer's instructions.

Benefits of MOLYKOTE D-321 R

• Air-curing dry-film lubricant
• Contains molybdenum disulfide and graphite
• High load-carrying capability
• Designed for low-speed and oscillating movement
• Helps reduce stick-slip
• High and low temperature performance
• Wide service temperature range
• High aging resistance
• Suitable for hard-to-reach surfaces
• Can provide lubrication under high-vacuum conditions
• Dry film does not have the same wet surface characteristics as conventional grease or oil

MOLYKOTE D-321 R vs. Conventional Grease

MOLYKOTE D-321 R is an anti-friction coating rather than a conventional grease. It is applied as a spray and cures to a dry lubricating film. This makes it useful in applications where a dry surface is preferred or where grease cannot be conveniently applied.

Greases remain appropriate for many bearing, gear, seal and other applications where a replenishable lubricant reservoir is required. D-321 R should therefore be selected based on the component manufacturer's specified lubrication method rather than simply substituting it for grease.

Technical Information

Ordering Information

BAC Part Number: D-321R

Product: MOLYKOTE D-321 R Anti-Friction Coating Spray

Package: 9.3 oz / 400 mL aerosol can

Shipping: Aerosol product; ground shipping restrictions may apply.

Business Aircraft Consumables supplies MOLYKOTE D-321 R for aircraft maintenance, MRO, industrial maintenance and other applications requiring a dry-film anti-friction coating. Verify the required product, package size and applicable technical documentation before ordering.

Frequently Asked Questions

What is MOLYKOTE D-321 R used for?

MOLYKOTE D-321 R is an air-curing dry-film anti-friction coating for high-load metal-to-metal applications involving slow to medium-fast movement. Typical applications include slides, guides, tracks, bushings, sleeves, threaded connections, fasteners, power screw drives and other highly stressed components.

Does MOLYKOTE D-321 R contain graphite?

Yes. DuPont specifies both graphite and molybdenum disulfide (MoS₂) as the solid lubricants in D-321 R.

Is MOLYKOTE D-321 R a grease?

No. D-321 R is an air-curing anti-friction coating that forms a dry lubricating film after application. It is not a conventional grease.

What temperature range does MOLYKOTE D-321 R have?

DuPont specifies a service temperature range of -180°C to 450°C (-292°F to 842°F).

How thick should the D-321 R dry film be?

DuPont recommends a dry-film thickness of approximately 5–20 μm.

How long does MOLYKOTE D-321 R take to dry?

At 23°C, DuPont states that the coating is touch-dry after approximately 5 minutes. Drying can be accelerated to approximately 1 minute with hot air at 80°C.

Can MOLYKOTE D-321 R be used on aircraft?

DuPont identifies aerospace maintenance applications for D-321 R, including maintenance of components that cannot be readily disassembled. However, the product should only be used on a specific aircraft, engine or component when permitted by the applicable maintenance documentation or component manufacturer's instructions.

Is MOLYKOTE D-321 R suitable for high-load applications?

Yes. The product is specifically designed for metal-to-metal combinations involving high loads and slow to medium-fast movement, and DuPont identifies high load-carrying capability as a performance benefit.