Grease versus Oil Lubrication of Wheel Bearings in Army Equipment

摘要

The US Army has the largest fleet of ground equipment in the United States. The number of vehicles is in the hundreds of thousands, and there are many types ranging from cars, trucks, and buses to a variety of tracked, wheeled, and mechanical/construction equipment and trailers. The mobility doctrine has led DoD to install wheels on many types of equipment so that all support activities, in addition to combat operations, can be performed locally in the field. These cars, trucks, buses, etc., are procured both commercially (off-the-shelf adoption for Army use) and through development programs in which contractors design and build equipment such as combat and tactical vehicles for Army use according to specifications developed by the Army. Wheel bearings are present in all of these vehicles, and the US Army has used grease lubrication of wheel bearings for many years. However, in some instances oil has been used for lubrication of these bearings. This is common practices for commercial axles, and this approach is continuing to be used more frequently by contractors and developing agencies as well. The advantages of oil as opposed to grease are higher operating temperatures and better heat transfer properties. The current technology in grease manufacture, however, extends the upper temperature limits of grease up to and beyond that of some oils. Thus, grease is the lubricant of choice for the lubrication of wheel bearings in Army equipment.