Molybdenum disulfide is a crystalline substance of a layered structure, which is characterized by a low coefficient of friction. In MoS2 layers, strong bonds are formed between sulfur and molybdenum atoms and very weak bonds between sulfur atoms. Thanks to this, the layers of crystals are able to slide, reducing friction between the working surfaces of units and mechanisms, as well as imparting additional extreme pressure properties to greases. Outwardly, such lubricants have a characteristic dark gray color with a slight metallic sheen.
Indeed, on a four-ball friction machine (BSM) used to analyze the anti-wear properties of lubricants, greases equipped with this additive show significantly higher welding load and critical load, as well as a small contact patch. What does this mean for us in practice? Under most typical bearing conditions, the properties of molybdenum disulphide are generally not required. When designing bearing units, equipment developers take into account the actual operating conditions of bearings and provide for the most optimal modes of operation and lubrication. For these purposes, mass lubricants with average properties are selected that can provide the appropriate lubrication regimes. As a rule, traditional greases based on lithium or lithium complex thickeners without special additives are recommended for these purposes. The extreme pressure properties of bulk greases are given by appropriate additives (EP - Extrime Pressure), and the stability of the oil film is determined by the viscosity of the base oil from which the grease is made.
The properties of molybdenum disulfide become indispensable when it is necessary to provide high extreme pressure properties without increasing the content of EP additives and without increasing the viscosity of the base oil. The first case is typical for high-temperature applications, when the lubricated unit operates at high specific or shock loads, but due to the viscosity of the base oil and EP additives, it is not possible to obtain the necessary welding load. The second case is typical, on the contrary, at low temperatures in a cold and arctic climate, when it is required to simultaneously provide a lubricant based on a low-viscosity base oil with high extreme pressure and low-temperature properties.
I propose to consider an example of the use of ARGO Elit MA grease, popular in the northern and arctic regions of Russia. This grease is produced on a low viscosity base oil that provides excellent low temperature properties, as well as pumpability in centralized lubrication systems of various mining equipment in the mining industry at temperatures down to -45⁰С. The addition of molybdenum disulfide in the Elit MA grease forms a reliable protective layer on the surface of the working parts of friction units operating under high mechanical loads and, especially, shock ones.
Another application example comes from the cement industry, where lubricants are required with good high temperature properties as well as increased protection at high unit loads and low rotational speeds. The most typical application of molybdenum disulphide greases is ARGO TermoMax grease in kiln rollers in cement production. These friction units are characterized by very low rotation speeds and high temperatures (up to +200⁰С). For these conditions, the lubricant must contain a high-viscosity base oil and have special protective properties at high specific pressures. When the base oil forms an unstable oil film on the running surfaces of bearings at high temperatures, a reliable protective layer of molybdenum disulfide comes to the rescue.
In conclusion, I would like to offer conclusions, but also warn the reader of this post against the unjustified use of lubricants with molybdenum disulfide. Lubricants with this antifriction additive have a strictly defined purpose and scope. So, earlier we considered the use of ARGO Elit M lubricant as a lubricant for the internal CV joint of front-wheel drive vehicles, paying attention to the features of the operation of similarly designed joints and the requirements for lubricants for them. This time I want to draw your attention to the fact that lubricants with molybdenum disulfide are traditionally used in low-speed, but highly mechanically loaded friction units, protecting them from intense wear at high specific and shock loads. But in high-speed bearings, molybdenum disulphide can create the opposite effect in the form of abrasive wear and internal heating of the assembly with a corresponding leakage of lubricant. For example, a high-speed car wheel bearing or an electric motor bearing may fail prematurely from molybdenum disulphide lubrication.
Molybdenum lubricants are considered the most popular elements used in various mechanisms and assemblies. Due to the physicochemical properties of molybdenum disulfide, they protect parts from excessive wear, early aging and fatigue of the metal and protect rubbing surfaces under strong thermal and mechanical loads.
The component is mined in the form of an ore with. Further, it is purified, as a result of which it is converted into dark-colored crystals, which, interacting with the metal, leave a trace of a gray tint with a green tint. Lubricants based on molybdenum disulphide are famous for their adhesion to metal surfaces of mechanisms. In simple terms, a surface subject to friction and direct mechanical stress is protected by a microscopic layer of lubricant, which, in turn, protects the part from physical damage, and also helps to reduce temperature indicators in the friction area.
Characteristics
Molybdenum-based grease has a number of advantages over other types.
The main advantages include stable operation under high extreme loads. Also, it does not lose its qualities with a critical decrease and increase in temperature, has an anti-corrosion property, and helps prevent wear and mechanical damage. Regardless of aggressive conditions, it provides the mechanism with a long lubrication moment. Molybdenum lubricants, in contrast to graphite materials, have significantly higher reductility. They can be produced in the form of aerosols, greases and oils. They are used in various engineering industries. Namely, in the automotive industry, machine tool building, to increase the service life of complex industrial mechanisms.
Material action
Due to their molecular structure, molybdenum lubricants perform excellent protective functions, while not interfering with the work of the main lubricant. Molybdenum disulfide includes one molybdenum atom and a couple of sulfur atoms, the interaction of which with the metal surface securely attaches the disulfide to the surfaces. The characteristic action of molybdenum is the formation of a viscous lubricant layer, the thickness of which is 5 microns, which, in turn, is equal to one and a half thousand anti-friction coatings. At the moment of friction of metals, the particles of the material move directly between themselves, which prevents direct contact of the surfaces of the parts, and, accordingly, reduces wear and overheating.
Plastic materials based on molybdenum
The characteristics of molybdenum work best when combined with other components. For example, it has enhanced protective properties and is able to additionally protect the elements of mechanisms from shock loads. The use of these types of lubricants significantly increases the degree of strength of the surfaces of parts.
They are widely used in the processing of bearings, gear mechanisms, to provide lubrication of various types of gearboxes.
Throttle Lubricants
The throttle valve is designed to regulate the supply of the fuel mixture to the engine cylinders by changing the cross section of the passage channel. At the moment the damper opens, the pressure in the intake system is equal to atmospheric, but when the damper is closed, the pressure decreases until a vacuum is formed. A throttle valve is located between the intake manifold and the air filter.
During operation, the damper becomes clogged, deposits from the products of combustion of fuel form on it.
Additionally, this regulatory mechanism receives mechanical damage during long-term operation. The axial play of the so-called valve contributes to the formation of small grooves in the body of the passage channel, as a result of which the fuel mixture enters more depleted. Subsequently, the stable operation of the motor changes, especially at idle. To increase the wear resistance of this mechanism and reduce the degree of damage, molybdenum grease is used for the throttle valve.
Molykote brand products can be attributed to one of these types. This is applied to the surface of the damper by special technological operations.
The positive side of the application
The advantages of using lubrication: friction between the contacting parts is reduced, tightness is increased, damper wedging is prevented, smooth movement of the throttle mechanism is ensured
In addition, molybdenum throttle lubricants retain their positive properties for a long time and are resistant to various aggressive environments. Motorists note that the use of this composition has a positive effect on the operation of the throttle and significantly extends its life.
Lubricant Hi-Gear HG5531-312
It is used as a method of processing a variety of mechanisms that are exposed to high temperatures and shock loads. The composition of the preparation includes finely dispersed molybdenum and components with a high threshold of resistance to elevated temperatures and pressure. The maximum pressure threshold is 7000 atmospheres, and the maximum temperature threshold is +250 degrees.
Molybdenum sulfide grease of this brand has a fairly wide range of applications:
- Chains and stars.
- and mechanisms.
- Gear mechanisms of open and closed types.
- Pulleys and cables.
- Shafts.
- Sliding and rolling bearings.
- Locks and latches.
- Coupling devices.
The grease has a high resistance to aggressive conditions. Works great in high humidity conditions, resistant to direct exposure to water. Protects surfaces from the formation of oxides and rust. It is resistant to acids and salts. At the same time, it is used as a molybdenum lubricant for injection molding machines in an aerosol, since it does not damage the structure of plastic and rubber products.
Mode of application
In use, the drug is quite simple - just read the instructions and start processing a particular part. Shake the bottle first. Then generously apply lubricant to the part and let it dry a little.
After that, the mechanism or a separate element can be put into operation. According to reviews, it is not recommended to lubricate the nodes with a large amount of a substance, since when heated, it expands and can penetrate through the seals to the outside.
MolyWay Li 732 Bearing Grease
This product is intended for the lubrication of plain bearings and rolling bearings, as well as for use in the heavy manufacturing industry. Contains molybdenum disulfide. Molybdenum is made from high viscosity oils and lithium soap. Additionally, it contains additives that help prevent the formation of corrosion and oxides, increased wear and adhesion. Due to the three percent content of molybdenum in the composition, the drug has anti-shock protective properties.
Molybdenum grease: application
Given the numerous reviews, it can be used not only for bearings, but also for other auto components. So, it can be used as a lubricant for CV joints. It is used as an alternative to graphite. It showed itself quite well when used as the main lubricant for the axles of tips and rods, ball bearings. Can also be used to lubricate door hinges and locks.
The temperature threshold for application is from minus forty to plus one hundred and twenty degrees.
The application of this agent significantly extends the service life of the elements of the mechanisms of vehicles and industrial equipment, and also contributes to the normal grinding of new parts.
Advantages of MolyWay
High resistance to oxidation and mechanical stress, excellent resistance to corrosion, ability to withstand significant force and shock loads, good adhesion reduces the likelihood of frequent application of lubricant.
Looking at the variety of lubricants using molybdenum disulfide, it's hard to figure out which one to choose. Therefore, you first need to decide for what purpose it is needed.
There are several types of this drug that may be for specific uses only, as well as general purpose lubricants. Additionally, you should pay attention to the release form, since many parts that require processing can be in hard-to-reach places, so the lubrication process for them should not be too burdensome. It is not recommended to purchase products of dubious origin, because this can lead to costly repairs.
So, we found out what molybdenum lubricants are.
Lubricants based on molybdenum disulfide are widely used and in demand in many areas. Molybdenum grease is effective in protecting hard-to-reach components (locks, hinges, hinges, etc.), as well as various mechanisms and parts operating under high loads, temperatures and extreme pressures. Allows to minimize the wear of parts in contact with each other. Indispensable for sliding elements, both heavily loaded and working with a large impact load: bearings, CV joints, ball and U-joints, planetary gearboxes, gear-screw (worm) gears, pressure valves.
Greases based on molybdenum sulfide form a film that serves as a layer of dry lubricant even after evaporation of the dispersion medium, thus friction knots occur even in emergency conditions and with sudden temperature fluctuations.
Molybdenum grease for wheel bearing
The use of molybdenum grease in a wheel bearing is quite justified, such greases have the properties of anti-accident materials, reduce bearing wear and noise, the resource of such a grease usually exceeds the bearing service life (more than 100,000 kilometers) and it is enough to apply it once for the entire service life. For wheel bearing lubrication, we recommend IPF EP-3 grease with molybdenum disulfide because:
- it provides excellent protection against corrosion even in the presence of water
- dense oil film prevents metal-metal friction and eliminates oil starvation due to the fact that it is not squeezed out of the friction zone under loads
- high mechanical stability - the structure does not collapse for a long time even under conditions of high pressure and high loads
- wide operating temperature range from minus 40 to plus 180 degrees
- high dropping point
- very low coefficient of friction
The origin of MoS 2 and the features of the operation of molybdenum lubricants.
MoS 2 - molybdenum disulfide. It is a natural compound of geothermal origin extracted from ore. It has the appearance of black crystals with a fibrous structure. Before being added to the lubricant, the extracted particles undergo a purification process. They leave a gray-green mark during friction, provide high adhesion with various types of metal surfaces, this is provided by sulfur atoms, which give it an affinity for the metal.
Plastic molybdenum greases work as follows:
- MoS 2 atoms, upon contact with the metal, are firmly fixed on its surface;
- create a dense layer on the surface in the form of a film, the thickness of which does not exceed 5 microns, this layer itself is a lubricant that prevents metal aging;
- molybdenum disulfide compounds move between two metal parts and exclude their direct contact;
- the result of the application is to prevent overheating and reduce the load on mechanisms and components.
Scope of molybdenum lubricants
Ready-made grease is in demand when needed in:
- improving the running-in efficiency of new parts and components;
- protection of load-bearing planes operating in severe conditions, and giving them extreme pressure properties;
- prevention of premature aging and wear of the metal.
Finds application in various industries:
- in the automotive business;
- in agricultural, construction, military and aerospace engineering;
- in industrial equipment;
- in machine tool building.
Distinctive properties of lubricants with molybdenum disulfide
During operation, molybdenum lubricants (with MoS2 in the composition) form a protective microfilm on the contacting surfaces of units and mechanisms, leveling them and preventing scuffing, reducing the temperature during friction.
Features of molybdenum greases:
- high rates of specific strength and bearing capacity;
- resistance to fretting corrosion, high temperature and pressure;
- low coefficient of frictional interaction (friction);
- chemical stability and separation effect;
- excellent bonding properties, as well as extreme pressure and anti-wear properties.
Molybdenum greases show improved protective properties and are recommended for shock loads - they create an additional layer, which increases the hardness and strength index, eliminates the risk of seizing.
Molybdenum lubricants are modern materials, to which ultrafine powder MoS2 (molybdenum disulfide) is added. Thanks to this, the products are able to repeatedly minimize wear and acquire improved water resistance, due to which they are actively used where conventional multi-purpose lubricants cannot cope even under critical and extreme loads.
They are of the greatest interest for servicing units and assemblies, the functionality of which involves the interface of several rubbing surfaces and constant shock loads and vibrations. For example, ball bearings and U-shaped joints of motor vehicles and special equipment, hub bearings, crank gears, turntables, transmission mechanisms.
Physical and chemical properties of MoS2
Due to its volcanic origin and inorganic nature, this substance is characterized by high thermal and oxidative stability, excellent resistance to extreme pressures and the ability to form an ultrathin protective film.
For use as an additive, the proportion of pure substance must be more than 96%, but compared to other solid lubricants, molybdenum disulphide powder is characterized by:
- yield strength > 3450 MPa;
- low viscosity properties;
- very low friction coefficient µ ≈ 0.03 ÷ 0.06;
- unique lubricity even in the range of cryogenic and high temperatures.
The substance belongs to the group of transition metals and has a characteristic layered structure. It does not react with solvents, acids and alkalis. The synergy of the sulphide layer and MoS2 provides extremely effective protection against corrosion and wear on steel surfaces. To activate the inhibitory qualities and improve the antiwear properties of lubricants, derivatives of dithiocarbamic acids (dithiocarbamines and molybdenum disulfide dithiophosphates) are widely used as additives, in addition, these compounds are distinguished by better solubility, they are often found and added to motor oil.
Industrial and production potential
The first lubricants containing highly dispersed powder of molybdenum disulfide were used in limited quantities and were intended mainly for the treatment of friction pairs of equipment and installations of the military defense complex and space and satellite applications. But a significant reduction in the cost of the process of obtaining this substance contributed to a radical expansion of the scope of molybdenum lubricants.
Today they are widely used in heavy and light industry and transport and demonstrate excellent performance in vacuum conditions and at extremely high pressures. Their use makes it possible to avoid seizure of the contact surfaces of heavily loaded low-speed mechanisms, effectively remove heat from the friction zone and reduce energy costs for starting, reversing and stopping mechanisms operating in intermittent mode.
Molybdenum lubricants are the best alternative to address wear and fretting corrosion in bearings subjected to heavy weight and shock loads, vibrations and high temperatures. Compared to analogues, they most effectively contribute to increasing the service life of CV joints and joints and give excellent results when running in mating surfaces of valve groups. But the key advantage of MoS2 is its compatibility with most of the thickeners used in today's lubricants, whether it be ceramic and titanium components or polyurea and Al-complex.
Despite the unique performance characteristics, the selection of materials must be carried out taking into account the speed factor, the class of cleanliness of the friction surface and the load. So for planes with increased and significant roughness, the size of powder particles of solid components can reach up to 7 microns, which will make it possible to replenish the natural loss of metal most effectively. But for more delicate surfaces, the particle size of MoS2 should be about 2 ÷ 3 microns. On average, the proportion of a substance is no more than 2% in each lubricant composition, as practice shows, an unreasonable increase can provoke undesirable oxidation processes.
Among the greases presented by INTERAVTO, you will find the best option for lubricants, which include MoS 2 , for various tasks, which will correspond to the upcoming loads, temperatures and pressures.
Running-in paste "LIMOL"
Modern production conditions impose severe requirements on the anti-friction, protective and physico-chemical properties of lubricants and cause toughening of the economic justification for their use, since in any industry today it is important to minimize the time and material costs for the maintenance and repair of equipment and ensure the maximum possible service life of parts and assemblies. The use of new lubricant products based on molybdenum disulfide, developed by the Russian company INTERAVTO, allows:
- radically solve the problem of wear of friction pairs;
- provide a greatly increased inter-lubrication interval;
- reduce technological downtime and the likelihood of accidents and breakdowns;
- simplify the running-in process of mating surfaces and minimize vibration and noise.
In hard operating conditions they are practically indispensable, as they resist washing out and extrusion, withstand critical loads and shear deformations. They form heavy-duty lubricating films on the surfaces of parts with any configuration and protect them from liquid and gaseous aggressive media.
Considering the use of molybdenum-containing lubricants in various industries and the specifics of their application conditions, INTERAVTO offers radically new products from this group, developed on the basis of the latest scientific achievements in the field of tribology. All of them have passed multi-stage testing at production sites and received excellent recommendations from leading engineers.
Moli-DL. Mineral high-temperature grease specially designed for extreme operating conditions associated with high loads (up to 7000 N), pressures and temperatures. In addition to molybdenum disulfide, it contains metal powders in ultrafine form, due to which it has a high bearing capacity, prevents jerky movement and slippage of parts, and thus ensures the standard starting and braking torques and smooth operation of the transmission. Efficiently removes heat and prevents the formation of scuffs, delaminations and burrs on machined parts and completely eliminates the setting of contact surfaces. Simplifies dismantling and increases the multiplicity of screwing threads.
Moliol. Multipurpose lithium grease containing MoS2 and original additive package. Thanks to this, it acquired unique properties, including the ability to withstand high shock loads and shear deformations and maintain its rheological characteristics in the range from -25 to 150 ˚С, as well as excellent hydrophobicity and adhesion. The use of lubricant has a stable anti-friction and lubricating effect in high-speed and low-speed units. It protects treated surfaces for a long time from contact with atmospheric and condensation moisture and aggressive substances and compounds in liquid and vapor state. Moliol is the optimal solution for lubricating the undercarriage of vehicles and heavy special equipment: bulldozers, loaders, excavators and asphalt pavers, as well as for servicing equipment in the polymer, woodworking and metallurgical industries. The product is inert to clogging, effectively dampens vibration vibrations and minimizes noise. Operable in damp and dusty environments. It has the properties of anti-crash lubrication and improves the running-in of surfaces. The lubricant is recommended for metal-to-metal friction pairs, but is also effective when processing flexible shafts in a sheath made of various polymeric materials. It is widely used in the printing industry, the production of wood materials and in the packaging lines for bulk building, detergent and abrasive materials.
IPF ER-3. Synthetic grease with high extreme pressure and antiwear properties and an extended operating temperature range. It is characterized by excellent colloidal stability, high adhesion and resistance to dropping and extrusion. Demonstrates precision resistance to evaporation of the dispersed medium and inertness to aging and clogging. It has a very long service life and can be used for the treatment of friction pairs of thermal equipment, agricultural processing stations and lines for the production of cement, gypsum and other particulate building materials. IPF EP-3 perfectly prevents rusting of steels, electrical and fretting corrosion. The grease is not prone to heat hardening and is highly water resistant.
How to choose and buy molybdenum grease
For proper selection of lubricant, we recommend contacting Interauto specialists, since the selection of lubricant depends on many factors of the working environment, equipment parameters and frequency of operation. To take into account all these factors, it is often necessary to fill out a questionnaire (to download it you can click on ), in this case we will select for you not only the most suitable material, but also the best one in terms of cost.
Molybdenum grease is one of the most common lubricants for industrial units and machine systems. And this is not surprising. Molybdenum disulphide (MoS 2) exhibits excellent extreme pressure and antiwear properties, helps prevent premature aging of the metal and protects friction points during heavy mechanical stress. The compound of molybdenum and sulfur is mined as an ore, then refined into black fibrous crystals that leave a grey-green trail when rubbed. Greases with molybdenum disulfide are characterized by high adhesion to metal surfaces. This means that a protective microfilm is formed on the surface of the part of the friction unit, which levels the working surface, preventing the formation of scratches and reducing the temperature in the friction area.
Distinctive properties of lubricants with the addition of molybdenum disulfide:
- High specific strength;
- Chemical stability;
- Temperature resistance;
- Low coefficient of friction;
- Good alloying properties;
- Anti-seize qualities.
LLC NPP Mapsol has molybdenum lubricants in its product line, which are perfect for use in machine tool building, the automotive industry when lubricating ball and roller bearings, worm gears and hard-to-reach assemblies.
Greases with molybdenum disulfide under the brand name "MAPSOL" are the best choice for servicing units and mechanisms operating under heavy loads and high temperatures.
How molybdenum disulfide (MoS 2) works
Grease based on molybdenum disulphide, due to its molecular structure, allows you to protect metal surfaces without interfering with the circulation of lubricant in the friction unit. Molybdenum disulfide consists of one molybdenum atom and two sulfur atoms, which, when interacting with the metal, are firmly attached to its surface. The secret of the action of molybdenum lies in the fact that a dense layer of lubricant forms a film that, with a thickness of only 5 microns, can include more than 1500 sliding surfaces. When friction occurs, the molybdenum disulfide compounds begin to move freely relative to each other, thereby preventing direct metal-to-metal contact, overheating of the part and reducing the load on the assembly.
Grease based on molybdenum disulfide and features of its effect on friction units
Molybdenum disulphide exhibits its protective properties even better in greases when combined with other components. Thus, molybdenum dusulfide in the composition of lithium greases is able to create an additional lubricating layer under shock loads, thereby preventing a high degree of metal wear and providing effective protection. The use of lubricants with molybdenum almost completely eliminates the risk of scoring or seizing, significantly reduces the coefficient of friction, and increases hardness and strength. Molybdenum greases have been successfully used to treat plain bearings, gears, valves operating under high pressure conditions, to lubricate worm and planetary gears and other mechanical parts.
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The properties and advantages of Molykote and EFELE disulphide-molybdenum lubricants are considered, some examples of their application are given.
Molybdenum disulfide is the most common form of existence of molybdenum in nature, an inorganic chemical compound of tetravalent molybdenum with divalent sulfur. The chemical formula of molybdenum disulfide is MoS 2.
In nature, molybdenum occurs only chemically associated with other elements in the form of ore.
Due to its external resemblance to galena - lead sulfide - this mineral was formerly called "molybdos", which means "like lead" in Greek. In 1778 the Swedish scientist Carl Wilhelm Scheele identified molybdenite as a metal sulfide, and in 1782 Peter Jacob Hjelm isolated the metal and named it molybdenum.
To date, large deposits of molybdenite have been discovered and are being developed in the mountains of Colorado (USA), China, Chile and Russia.
Molybdenum disulphide found its use as a lubricant in 1935. The test rig, which had been designed to simulate aircraft vibrations, proved to be inoperable - parts of its heavily loaded friction units moved in jumps. Attempts to eliminate the problem using lubricants available at that time did not bring positive results. The task of ensuring the smooth movement of the units of the installation was solved by the German engineer Alfred Sonntag, who put into practice information about the properties of molybdenite dating back to the 18th century. However, along with an effective reduction in the friction coefficient, molybdenum disulfide caused wear of the units, since the natural mineral contained impurities of abrasive quartzite, and it was impossible to obtain a pure substance at the existing technological level.
In 1940, Sonntag founded the Sonntag Scientific Corporation, which developed methods for purifying molybdenite from impurities and obtaining a pure product. In 1948, he formed Alpha Molykote, which became the world's first manufacturer of molybdenum disulphide lubricants.
In the early 1970s, the mechanism of the lubricating action of molybdenum disulfide was first studied by scanning electron microscopy. As a result, it was found that the unique anti-friction properties of this solid are due to its anisotropic layered structure and the ability to fill the depressions of surface microroughness, forming a lubricating layer in the form of a smooth and very slippery film. In addition, it turned out that molybdenum disulfide is able to adhere to the surface of metals due to its high adhesion, and its coefficient of friction remains low even at extremely high pressures.
The introduction of solid lubricants into the composition of greases gives them new properties. The formation of two lubricating layers (grease and solid lubricant) significantly increases the load-bearing capacity of such products. As solid lubricants, graphite (graphite lubricants), molybdenum disulfide (molybdenum disulfide or molybdenum lubricants), polytetrafluoroethylene (PTFE or fluoroplastic lubricants) and other special additives are usually used.
The main advantage of molybdenum greases over traditional ones is that they work stably under extremely high loads, at high and low temperatures, effectively prevent increased wear, fretting corrosion, scuffing, and provide long-term lubrication under aggressive environmental factors. Molybdenum disulfide lubricants, compared to graphite lubricants, have higher antifriction properties, have a greater bearing capacity and can operate in vacuum conditions.
Experimental studies on a four-ball machine found that molybdenum disulfide and graphite exhibit synergistic interaction and enhance the positive properties of each other (see Fig. 1).
Rice. 1. Graph of wear versus load and the content of graphite and molybdenum disulfide in the lubricant
The results of the experiment showed that the antifriction properties of molybdenum disulfide under any conditions exceed the properties of graphite. At certain proportions of the suspension of these components in mineral oil, wear is reduced by up to 6 times compared with the use of pure graphite, and under certain loading conditions, the composition of these solid lubricants is more effective than pure molybdenum disulfide.
The Molykote and EFELE range of lubricants includes greases both with pure molybdenum disulfide and with fillers in the form of its mixture with graphite.
The properties and application examples of Molykote and EFELE greases containing pure molybdenum disulphide are shown in the following table.
| Description | Application examples |
| (-30...+120 °C) | |
| Multipurpose lithium grease with extreme pressure additives and molybdenum disulphide. Operable in a humid environment, has an increased bearing capacity, excellent anti-wear and anti-corrosion properties. |
Highly loaded bearings of general industrial equipment; Chassis of cars, tractors, excavators, bulldozers, loaders and other vehicles operating in difficult operating conditions; Bearings for electric motors and fans. |
| (-25…+120 °C) | |
| Lithium mineral-based moisture resistant grease with a wide operating temperature range, for extremely high loads and moderate speeds, with high adhesion and anti-corrosion properties, for metal-to-metal combinations. Consistency class according to NGLI – 2…3 |
Transmission mechanisms: open and closed gears, including flexographic printing machines; cargo-passenger lifts, oilfield and geological exploration equipment, mixers for bulk and pasty products; Spindles; Central lubrication systems, e.g. tool grinders |
| (-40…+177 °C) | |
| Water-resistant synthetic (PAO) cold and heat-resistant lithium complex thickened grease for long-term lubrication of highly loaded and high-speed components subject to vibration, with high adhesion, anti-corrosion and anti-fretting properties, for metal-metal, metal-plastic and metal-elastomer combinations. Consistency class according to NGLI - 2 | Rolling bearings, including support bearings for wheels of kiln trolleys, needle bearings for cardans of unequal angular velocities, bearings for curing presses, steering shafts for automobiles, wheel hubs, pressure shafts for edge banding machines, metalworking rolling equipment, machines for slitting corrugated board, drives for industrial washing machines, oilfield and geological exploration equipment, exhaust ventilation systems, centrifuges for separating liquid raw materials, injection molding machines, hydraulic straightening presses; Sliding bearings, including bearings of electric motors, transport vehicles, exhaust ventilation systems, centrifuges for the separation of liquid raw materials; Sliding guides; Spindles; hinges; Sleeve-shaft connections, including: overhead cranes, spreading rollers of edge banding machines; Shafts, including hydraulic straightening presses; Transfer mechanisms: |
| (-35…+130 °C) | |
| Waterproof lithium-zinc grease for long-term lubrication of highly loaded components, with a wide operating temperature range, high anti-corrosion and anti-fretting properties, for metal-to-metal combinations. Consistency class according to NGLI - 2 |
Rolling bearings, for example, steering shaft bearings, car wheel hubs; Transmission mechanisms, including rack and pinion gears; Hinges, for example, pairs of "finger-liner" in car suspensions, steering rod joints; Lever mechanisms, including: lever drives of automobile transverse steering rods, lever mechanisms of automobile bridges and hinges |
