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The Permawick Company offers a complete product line of bearing lubricants designed to provide the ultimate in performance in Fractional Horsepower motors. In addition, Permawick provides a technologically advanced selection of mineral and synthetic industrial lubricants which are blended with synergistic additive packages to maintain high film strength under the most adverse of conditions and always provide thin-film boundary lubrication.
Permawick lubricants meet the demands placed on the electric motor bearings such as frequent starts and stops, low speed operation, and hammering effects on unloaded bearings due to magnetic pull on the rotors. With the customer’s needs in mind, Permawick has developed lubricants to meet a myriad of requirements such as:
- Long service life
- Wide useful operating temperature ranges
- Oxidation and thermal resistance
- High shear stability
- Resistance to corrosion
Permawick makes available lubricants for a variety of applications such as compressor lubricants, circulating oils, impregnating fluids, bearing lubricants, hydraulic oils, turbine oils, industrial gear oils, and lubricants for other mechanisms.
The safe formulation, manufacture and use of the products is a commitment shared throughout the Permawick organization and is realized in our Material Safety Data Sheets. Our MSDS are reviewed periodically and contain the most current product safety information based on in-house and outside laboratory testing, along with input from regulatory and trade associations.
Permawick’s MSDS follow the ANSI format and conform to the OSHA Hazard Communication Standard and WHMIS regulations. The most current MSDS for our products can be obtained by contacting :
Permawick Company: 255 E. Brown Street suite 100nbsp; Birmingham, Michigan 480009 Tel: (248) 433-3500 Fax: (248)433-1824 or (248) 594-3433
Various types of oils are used to provide fluid-film lubrication for industrial applications. In fluid -film lubrication a coherent film of lubricant exists between two sliding surfaces to minimize resistance and therefore, friction. Furthermore, lubricants are used in conditions that do not permit the formation of a separating lubricant film by common hydrodynamic action. Under these conditions the lubricant or some of its active components are deposited on the metal surface thus reducing metal to metal contact and frictional resistance. This is known as boundary lubrication. The additives used to formulate the industrial lubricants are selected on the basis the of the equipment operating requirements in order to afford adequate protection against extreme wear and damage caused by frequent starts, stops and changes of direction.
The additives are commonly referred to as tribological additives. The most common additives which contribute to lubricant performance are:
- Antioxidants which extend service life
- Antiwear / EP additives which offer surface protection
- Antirust additives which slow rust formation
- Anticorrosives which slow corrosion
- Viscosity Index Improvers which reduce rate of change of viscosity with temperature
- Pour Point Depressants which lower pour points
Lubricant technology has steadily developed since the industrial evolution and has its roots in the study of bearings. Bearings are important elements used in all branches of industrial machinery. By applying a sliding (plain bearings) or rolling action (rolling - element bearings) they allow smooth low friction linear or rotary motion between two surfaces. The lubricant functions to keep the surfaces apart by providing a fluid film supplied under pressure preventing metal to metal interaction and thus reducing friction and wear. The plain bearings lubricated in this fashion are known as full fluid-film bearings. The lubrication of these bearings has more variability than rolling-action bearings. Plain bearings which are lighly loaded and operate at high speeds need a low viscosity plain mineral oil while higher loads and lower speeds point toward higher viscosity oils.
Another factor that influences bearing performance is the elastohydrodynamic (EHD) properties of the lubricant. EHD occurs in rolling-element bearings and other high stress applications such as gears. The bearings squeeze the lubricant between the surfaces. As a result the lubricant increases in viscosity which allows the lubricant to withstand high contact stresses and prevents metal to metal contact.
Industrial lubrication does not stop with bearings. Further lubrication is required for the equipment and for any other metal working operations. Within this category of industrial lubricants are also compressor lubricants, hydraulic fluids, industrial gear lubricants, turbine lubricants, and metal working fluids.
Because of its availability and low cost, the lubricant of choice has been mineral oil. However, with industry dictating ever increasing demands on equipment, speed, and efficiency, the need has risen for lubricants that can successfully withstand increased temperatures and increased friction. For this purpose synthetic and semi-synthetic fluids have been developed.
PROPERTIES OF MINERAL OILS
Typically most industrial liquid bearing lubricants are mineral oils of different viscosities blended to meet certain performance specifications. Historically mineral oils have dominated the market due to their price, performance and availability. Lubricant performance is dependent on the physical and chemical properties of the basestocks and additives that are used to formulate them. The specifications used to evaluate these properties relate to the long term performance of the finished product. The properties are used as a quality control measure in the manufacture of lubricants. Various physical properties and their significance include:
- Viscosity - affects the minimization of friction and wear reduction
- Low temperature fluidity - lowest operating temperatures before the fluid cease to flow
- High temperature properties / Volatility - indication of the tendency of an oil to be lost through vaporization under elevated temperature conditions
- Foaming tendency - tendency to foam during agitation
- Demulsibility - abililty to separate from water and not to form a permanent emulsion
- Density - lubricants are formulated by weight
- Pressure / Viscosity characteristics - tendency of an oil to get thicker under pressure
- Surface properties - surface tension which affects foaming
- Viscosity / Temperature characteristics - variation of viscosity with temperature
- Flash point - below which is highest operating temperature before autoignition
The chemical properties of the mineral oil basestocks will have a long term effect on the finished lubricant. If not selected under specifications serious problems could occur. These properties include:
- Corrosion - reaction with metal parts to cause rust
- Oxidation - causes oil degradation and loss of performance
- Carbon Residue - carbonaceous degradation products (sludge) formed at high temperatures
- Seal Compatibility - the degree of seal swell that a lubricant has on rubber or plastic seals
- Sulfur content - the inherent amount in base oils which acts as a natural oxidation stabilizer
Another important basestock characteristic is the compositional category into which it falls. Most base oils produced are paraffinic with excellent viscosity / temperature characteristics and excellent thermal stability which makes them top candidates as industrial oils. The term paraffinic refers to the chemical structure which will form a wax like structure at lower temperatures. The paraffinic basestocks that are selected for lubricant use are solvent extracted and / or hydrotreated to improve oxidative stability and viscosity / temperature characteristics.
Another lubricant candidate are the naphthenics which have a more limited range of use but have low pour points and excellent solvency which also makes them useful lubricant candidates. Other base oil categories include process oils, electrical oils, white oils. These oils alone are not general industrial lubricant candidates but may be blended with paraffinic basestocks to produce custom lubricants.
The Permawick Company offers a selection of mineral oil based lubricants that provide the ULTIMATE in performance for FHP bearings and are the INDUSTRY STANDARD in bearing lubrication. In addition, Permawick offers excellent circulating oils which provide long term dependable lubrication and resist high temperatures. Our mineral oil line has a useful temperature range of -20F to 200F.
PROPERTIES OF SYNTHETIC LUBRICANTS
Synthetic lubricant technology has been around since the early 1930s when it was simultaneously developed by the US and Germany. However, commercial significance did not come into play until after World War II. With the advancing technology of industrial equipment the need for lubricants that could withstand a wide range of operating temperatures had considerably increased.
Synthetic lubricants are made from man-made basestocks derived from pure hydrocarbons. Because these basestocks are manufactured under contolled conditions to meet strict specifications, lubricants with excellent thermal stability, high flash points, low toxicity and excellent biodegradability have been formulated.
The synthetic base oils do not contain any naturally occurring impurities or variations as do mineral oils. The natural impurities in crude oils may cause chemical reactions such as corrosion which attacks metal surfaces or sludge formation due to oxidation. These factors decrease the useful life of a mineral oil. On the other hand, synthetics enjoy a long life span that withstand even the harshest environments without breakdown due to contamination.
The high viscosity index of the synthetic base oils indicates dependable viscosities over an expanded temperature range. Because of their excellent stability the service life is longer so lubricant change intervals are increased and overhaul intervals lengthened. Synthetics are nonreactive with parts that are not metallic and also provide optimal corrosion protection for the metallic components. Since synthetics are man-made there is no carbon residue as with mineral oils so filter life is also increased. All of this means less downtime and increased cost savings!
Permawick presents four exceptional families of synthetic lubricants guaranteed to suit your needs: Polyolesters, Polyalphaolefins, Diesters, and Perfluoropolyethers.
DIESTERS AND POLYOLESTERS
Synthetic esters compose the majority of synthetic industrial lubricants. They provide natural lubricity and have good thermal stability. One of the factors contributing to this stability is the inherent low volatility / low evaporation rate and good oxidation resistance.
The esters have excellent low temperature fluidity properties which enable lubricant flow down to -80F. At the opposite end, flash and autoignition points are high which enable their use at temperatures as high as 300F. These properties account for the operating efficiency of synthetic esters at high or ambient temperatures and also allow heat to be absorbed and carried away so that the system operates at a cooler temperature in applications such as air or natural gas compressors.
Synthetic esters have outstanding viscometric behavior. With their high viscosity index (VI) they maintain their viscosity throughout a wide temperature range while maintaining high film strength. Because of their chemical composition, the synthetic esters are compatible with mineral oils. This allows replacement of mineral oil based lubricants with synthetics without the need for extra flushing or fear of contamination.
Good compatibility is seen with plastics composed of the following materials: acetals, phenolics, polyamide-imides, polyamides, polyetherimides, polyimides, PTFE, and terephthalate. Good compatibility is also seen with fluoroelastomers.These lubricants are of a low ecotoxic nature. They are not soluble in water and have an environmental ranking of zero (not water endangering). Their biodegradability is high ranging from 75% up to 100%. Synthetic esters are safer than mineral oils . The chance of a reaction from inhalation, ingestion, or skin irritation is very low
Applications:
Compressor oils - both air and natural gas
Hydraulic and turbine oils
Gear oils
Bearing lubricants
Extreme pressure lubricants
The polyalphaolefins are popular as compressor lubricants, especially for rotary compressors. Polyalphaolefins are hydrolytically stable over a long term and separate readily from water. Their chemistry defines them as clean products that are chemically, oxidatively and thermally stable and corrosion resistant. These qualities indicate reduced sludge and gum formation. Filters do not get clogged as fast as they do with conventional mineral oils. Filter life is increased as are lubricant change-out intervals. Equipment down time is definetely decreased. All this points to energy cost savings as compared to the use of conventional mineral oils.
The high viscosity index and low pour points indicate excellent low temperature fluidity down to as low as -50 F. In addition, the flash and fire points of these lubricants are about 100 F higher than conventional mineral oils which are indicative of a greater margin of operating safety. The upper operational limit may be as high as 400 F.
The polyalphaoelfins mix easily with mineral oils and other synthetics. This makes conversion to this synthetic line easy without the worry of cross-contamination.
Polyalphaolefins are compatible with most plastics. However, elastomeric compatibility is limited to fluoroelastomers, neoprenes, and nitriles. Other elastomers may undergo shrinkage and hardening.
Applications
Rotary compressor lubricants
Impregnating fluids
Crankcase oils
Industrial bearings and gears
Gas compressor lubricant
Use with ammonia gas
Perfluoropolyethers are designed for performance in harsh environments with an operating range of -30F to 500F while still maintaining excellent lubricity and inertness. Also PFPE are not soluble in water.
Very high viscosity index and low pour points indicate excellent temperature stability and fluidity.
PFPE are compatible with all plastics, elastomers, rubber seals and gaskets,and O-rings.
Applications
Extreme temperature lubricant
Aerospace lubricant
The synthetic hydrocarbon blends combine the qualities of the mineral oils and the long service life of the synthetics. These blends have the naturally occurring sulfur and nitrogen which contribute to the natural antioxidancy of mineral oils.
The pour points are much lower than conventional mineral oils. The viscosity index is also higher. Both of these properties indicate excellent low temperature flow down to -50F. On the other hand, the semi-synthetics have the thermal stability and higher flash points . This allows operation up to 300F without sacrificing outstanding film and wear protection over a wide temperature range.
These oils have a low ash content and are oxidation resistant which means a longer service life before lubricant changeout.
The semisynthetics are also compatible with plastics.
Application
Bearing lubricant
Gas compressor lubricant
COMMONLY USED OIL INDUSTRY TESTS
These tests are used to evaluate the performance of the oils as they are being developed and manufactured. These same tests are used to evaluate basestocks.
Color (ASTM D1500)
Color is used as a quality rating as a discoloration is readily visible and may be indicative of adverse chemical reactions such as oxidation or of product contamination. Color is sometimes also used as a means of visual identification.
Corrosion, Copper Strip (ASTM D130)
This test is used to assess the degree of metallic erosion that can result from oxidation or other chemical reactions with metal surfaces. For the finished product this test is also used to ensure the presence of anti-rust and anti-corrosion properties and additives in the lubricants.
Demulsibility Test (ASTM D2711)
Demulsibility is used to determine the ability of a lubricant and oil to separate. Water that remains in emulsion with a lubricant may cause corrosion, adversely affect pumpability, and severely affect the anti-wear properties of that lubricant.
The demulsibility test is used to test hydraulic lubricants that will be exposed to steam and water and do not contain anti-wear additives.
Evaporation Test (ASTM 972)
The purpose of this test is to determine the amount of lubricant that evaporates over a period of time at an elevated temperature. This measure is referred to as the volatility. The information is then used to determine the stability and suitability of a lubricant for a specific use.
Falex Test EP Pin and V-Block Test (ASTM D3233)
The purpose of this test is to evaluate the extreme - pressure properties of a lubricant by measuring bearing load and the resulting wear.
Flash Point / Fire Point (ASTM D92)
The flash point test is used to determine the overall flammability of the lubricant.
From this information is derived the safe upper operating temperature limit for that lubricant .
Four-Ball Test (ASTM D2266, ASTM D2783)
These are two similar tests used to evaluate the anti-wear qualities, extreme-pressure properties, frictional characteristics, and load carrying capabilities of a lubricant.
Infrared Spectroscopy Analysis
The general purpose of this analysis is to provide a fingerprint of the fluid and to compare that to a known standard. This scan is not only used to confirm that all the components of the formulation are present but to also indicate any contaminants that may be present.
ISO VG (ASTM D2422)
The ISO VG system was designed to establish a classification of definite viscosity levels so that suppliers, users, and equipment designers would have a common and uniform basis for designating fluids. Viscosity is the only criterion and this classification does not imply any quality evaluation.
Kinematic Viscosity (ASTM D445)
Viscosity is the measure of a lubricant’s resistance to flow under gravity. It is expressed in terms of the time required for a standard amount of fluid to flow at a certain temperature through a standard calibrated orifice. Correct equipment operation depends on the use of lubricants of a specific viscosity. Furthermore, viscosity is used to determine proper handling and storage procedures.
Neutralization Number (D664)
The neutralization number of a lubricant is and indication of its acidity. The acidic constituents are present as additives or products of oxidation. The acid number is used as a quality control guide.
Pour Point (ASTM D97)
Pour point is the lowest temperature that an oil will pour or flow. This value is used to determine the safe useful low temperatures of a lubricant and its suitability for that application.
SUS Viscosity (ASTM D88)
Saybolt Universal Seconds - A measurement used by some suppliers and users which is approximately five times the kinematic viscosity in centistokes.
Viscosity Index (ASTM D2270)
This is a scale which is used to show the rate of change of viscosity with temperature. For lubricant finished product a high viscosity index is desirable. Paraffinic mineral oils have a VI of about 100 while synthetic fluids are considerably higher.
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