AEROSHELL GREASES
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AEROSHELL GREASES AEROSHELL GREASES THE DEFINITION OF A GREASE IS: “A solid or semi-solid lubricant comprising a dispersion of a thickening agent in a liquid lubricant to which various additives have been added to improve particular properties”. Within the aviation industry, there are many grease lubricated applications covering a very wide range of performance requirements. Those requirements are being increasingly stretched through new technology developments and extended service intervals. Greases, depending on the thickening agent, are broadly classified as either soap-based or non-soap-based. The soap-based greases include, for example, aluminum, calcium, sodium or lithium soaps; the non-soaps silica gel, clay and substituted urea. The low melting points and water solubility of some soap greases limit their usefulness. As a result alternative thickening agents have been developed – soap-complex thickened greases, and non-soap greases with a much higher or no melting point. These thickening agents were developed for greases needing superior high temperature performance characteristics. Shell’s search for thickeners without the limitations of the simple soap-type, led to a family of proprietary technologies including our ‘Microgel®’ and Lithium-Complex systems. Microgel® greases rely on an inorganic grease thickening agent, based on hectorite clay, which has several advantages over simple soap-type thickeners. It provides the AeroShell greases in which it is used with excellent physical properties, as shown below. Those properties make them particularly suitable for multi-purpose as well as specialised applications. 1. No melting point, within any conceivable temperature range for aircraft greases. 2. Very little change in consistency with variation in temperature. 3. Extremely good load carrying ability without the need for extreme pressure additive. 4. xcellent water resistance due to the use of tenacious waterproofing agents developed E by Shell. 5. Low oil separation or ‘bleeding’, because of the high gelling efficiency. During recent years, the number of greases required for aircraft lubrication/maintenance has been reduced by more extensive use of multi-purpose greases. However, because of commercial and technological limitations, special greases are still required. Most aircraft grease requirements are covered by the products in the AeroShell grease range. Many different grease formulations have been developed to meet specific requirements. One of Shell’s recent objectives, as a major supplier of aviation greases, has been the development of wide performance range products where a single grease can cover a multitude of a

To minimise the number of greases required per aircraft, the most widely used specification in the aviation industry today is the general purpose grease to MIL-PRF-23827. In the early 2000's the Boeing Company introduced a multi-purpose grease specification (BMS 3-33) to replace many of the different greases previously required in support of Boeing aircraft. This has led to the development of the accompanying specification SAE AMS 3052. The only grease to meet the most challenging set of requirements of the initial BMS 3-33A specification has been AeroShell Grease 33. This ground breaking...

GREASE WITH ENHANCED CORROSION INHIBITION AeroShell Grease 33 AeroShell Grease 64 - (with 5% molybdenum disulphide) AeroShell Grease 33 has enhanced corrosion resistance, and resistance to washout from water, de-icing fluids and other maintenance fluids. AeroShell Grease 64 is not subject to any speed restrictions and is widely accepted as an advanced multi-purpose grease. GENERAL PURPOSE GREASES WHICH HAVE A LIMITED OPERATING TEMPERATURE RANGE AeroShell Grease 6 AeroShell Grease 14 AeroShell Grease 6 has a useful temperature range of -40°C to +121°C, good load carrying ability and is...

AEROSHELL GREASES APPLICATIONS Whenever an aircraft is certified, all of the greases are specified for each application point on the type certificate. The Type Certificate will specify, either by specification number or by specific brand names, those greases which are qualified to be used. The U.S. Federal Aviation Administration (FAA) regulations state that only greases qualified for specific applications can be used in certified aircraft. Therefore, it is the responsibility of the aircraft owner or designated representative to determine which greases should be used. The useful operating...

AEROSHELL GREASES Elastomer/Plastic Mineral Oil Based Synthetic Synthetic Ester Greases Hydrocarbon Based Greases Based Greases Flurocarbon (Viton) Very Good Very Good Very Good Acylonitrile Good Good Poor to Good (high nitrile content is better) Polyester Good Good Poor to Fair Silicone Poor to Good Poor to Good Poor to Fair Teflon Very Good Very Good Very Good Nylon Poor to Good Poor to Good Poor Buna-S Poor Poor Poor Perbunan Good Good Fair to Good Methacrylate Good Good Poor to Fair Neoprene Fair to Good Fair to Good Poor Natural Rubber Poor to Fair Poor to Fair Poor Polyethylene Good...

AEROSHELL GREASES Always consult the Aircraft Maintenance Manual, Maintenance Planning Document or Component Overhaul Manual, and any associated Service Bulletins for advice on the correct grade of grease to be used in a particular mechanism and on the method of application and/or replacement of that grease. In particular, the latest issues of the following publications should be consulted for the most up-to-date advice: B oeing Service Letter 707-SL-20-012-C/727-SL-20-022C/737-SL-20-027-C/747-SL-20044-C/757-SL-20-022-C/767-SL-20-022-C/777-SL-20-006-C “Summary of Most Commonly Used Greases...

AEROSHELL GREASES AeroShell Grease 5 is a high temperature grease composed of a mineral oil thickened with Microgel®, possessing good load-carrying ability. It is inhibited against oxidation and corrosion and has excellent resistance to water. The useful operating temperature range is -23°C to +177°C. APPLICATIONS AeroShell Grease 5 is particularly effective for use as a wheel bearing grease, especially when landing speeds are high, and is suitable for the lubrication of aircraft and engine accessories operating at high speeds and at relatively high temperatures, e.g. magnetos, generators...