Without SFL
Fretting and galling of the substrate
With SFL
Protective layer created between substrates
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DRY Film Lubricants & Liquid Coatings
What are Dry Film Lubricants?
“Dry Film Lubricants”,(DFLs) also called solid film lubricants (SFLs), are:
- Materials with inherent lubricant properties.
- Firmly bonded to the surface of a substrate.
- Applied in the liquid state, generally by spray, tumble coater, or bath immersion.
Unlike wet lubricants, i.e. oil, grease that stay ‘wet’ while on the part, dry film lubricants go on wet, but then dry on the part it has been applied to. Particles do not stick to dry lube. Dry lube does not require any maintenance like wet lube. DFLs can be powder or liquid coatings such as PTFE, Xylan®, Epoxy, Polyester or Urethane.
The range of coatings includes environmentally friendly and REACH compliant coatings, as well as air cured, high temperature and PTFE. Among the solid film lubricants coatings we offer are Everlube®, Microseal®, Lube-Lok®, Lubri-Bond®, Ecoalube®, Ever-Slik®, Esnalube™, Perma-Slik®, Electrobond®, Flurene® , Formkote® and Henco-Mask™.
Dry film lubricants are made up of a combination of resin binders and lubricating pigments. The resin holds the lubricating pigment in place so that a layer interposes between the rubbing surfaces. As the surfaces move, the coating prevents direct contact of the substrate materials.
DFLs create a “Slippery” Factor
Properties of Dry/Solid Film Lubricants
Solid film lubricants (SFLs) have varying properties, depending on their structure and composition. For example, SFLs excel in:
- High load applications
- Applications where a very low coefficient of friction is desired
- High temperature environments.
- Used to improve chemical resistance to attack, abrasion and corrosion.
- Performance-enhancing benefits such as corrosion protection, wear resistance, electrical insulation, electromagnetic shielding and chemical agent resistance.
Benefits of Dry Film Lubricants
The key factors for PTFE coatings are:
- They are highly flexible
- Very chemically resistant
- Have excellent non-stick characteristics
- Are electrically resistant
- And offer a very low coefficient of friction, especially in lower load carrying applications
How do Dry or Solid Film Lubricants Work?
There are two main categories of dry film lubricants: crystalline lattice (lamella) type structures, including Molybdenum Disulfide, Tungsten Disulfide, and Graphite and Fluorocarbons, such as PTFE.
For crystalline type structures, such as Molybdenum Disulfide (MoS2) and Tungsten Disulfide (WS2), the shear forces between the layers are weak which results in increased lubricity between the sliding surfaces.
PTFE is a white, opaque synthetic fluoropolymer that provides lubrication in continuous use up to 260oC (500oF). The fluorocarbon molecule is structured such that the fluorine atoms surrounding the carbon atoms prevent any other atoms from getting near the carbon, preventing any further reaction. For this reason, PTFE is very unreactive which causes it to have a very low coefficient of friction and allows things to slide across its surface very easily.
Selecting the Correct Dry Film Lubricant
| What properties are desired | What is the environment |
|---|---|
| Load carrying capacity | Temperature |
| Low coefficient of friction | High vacuum |
| Corrosion resistance | Moisture / Humidity |
| Electrical properties | Presence of oxygen |
| Radiation | |
Types of Dry Film Lubricants
| properties | Molybdenum Disulfide | Graphite | PTFE |
|---|---|---|---|
| Load carrying capacity | >250 ksi | <50 ksi | <20 ksi |
| Coefficient of friction | 0.04-0.08 | 0.04-0.10 | 0.02-0.04 |
| Affect of moisture | Negative | Positive | None |
| Electrical conductivity | Not conductive | Conductive | Not conductive |
| Max operating temp in air | 750F | 1200F | 500F |
| Operation in fluids /lubes | Break-in only | Break-in only | Yes |
| Key strength | High loads, operates in vacuum and cryogenic environments | Moderate loads, high operating temp., electrically conductive | Does not lubricate sacrificially, clean environments, coatings can be decorative |
Where are Dry Film Lubricants Used?
Typical Applications
Fasteners: Torque/tension control, anti-galling, corrosion resistance
Couplings: Lubrication, anti-seize, chemical & corrosion resistance
Valves: Chemical & abrasion resistance, anti-seize
Pumps: Break-in lubrication, wear-life extension, chemical resistance
Gears: Close tolerance, precision gear lubrication, break-in lubrication
Bearings – Operation in vacuum or dirty environment, temperature extremes
Turbines: Turbine blade root sections and disk slots to aid in assembly, disassembly and reduces fretting and galling.
Firearms: Wear resistance, protection against corrosion, durability, lubricity, and decreased friction.
Typical Environments
| Chemical and corrosion | Delays or prevents corrosion |
| Abrasion resistance / reduced wear | Withstands loads in excess of 250 ksi |
| Friction | Reduces coefficient of friction |
| Lubrication | Does not attract containments like “wet lubes” |
| No maintenance required | |
| Water Based Coatings | Lower VOCs, easy to apply |
| Temperature | From -395ºF (-237ºC) to over 2000ºF (1093ºC) |
Smaller electronic components are particularly susceptible to damage or failure due to electrostatic discharge. EMI/RFI shielding blocks unwanted external and/or internal electromagnetic waves from emitting and interfering with other circuits or devices.
Recent News
- November 11, 2020
Curtiss-Wright Recognized as a Whitford Recommended Coater - September 30, 2020
Curtiss-Wright’s Everlube® R-75 Certified to NSF-61 - July 27, 2020
Curtiss-Wright’s Microseal® Supports NASA’s Mars 2020 Mission