A grease gun (pneumatic), also called a hand-pump, is a tool used for lubricating grease and other fluids in hard-to-reach places. It is an efficient tool because it can reach into places that a normal brush or rag cannot, as well as being a less-threatening tool compared to a jack-hammer, anvil, or a wrecking ball. There are four kinds of grease gun to choose from:
Hand-Pump – The earliest form of grease guns (and the most popular today) is called a “hand pump.” It was invented in the late 19th century. These devices use a piston to apply grease in hard-to-reach areas, such as under a piece of machinery, on or above a deck, or in an airplane hangar. They are powered by a hand crank similar to that of a hand pump or sewing machine.
Hand-Pumps work through a set of gears and a small barrel, suction cups, and a nozzle. The pump rotates a small barrel at high pressure and pumps the grease into a larger area through a small tube. An air release valve on the end of the tube allows excess air to escape and minimize waste. One drawback is that when the pressure rises to ambient atmospheric levels, a build-up of grease may cause a vacuum. This can result in damage to nearby objects or injury to the user if the gun is not properly maintained. Also, a hand-pump may only be able to pump enough grease at a time to adequately lubricate the rotating parts of the barrel, resulting in an uneven pumping action.
Another type of grease gun is the rotary screw air cleaner, sometimes called a rotary vane cleaner, or rotary screw auger. It is similar to the hand-pump device, except that it is powered by an electric motor. It uses a screw or bolt to apply the grease, and its design prevents it from spreading across a large surface area. It can be used to remove grease from many different materials, including metal and vinyl. Because its design keeps the grease from spreading, it has the ability to remove stubborn dirt and stains without causing cross-contamination.
The rotary vane cleaner does have one significant advantage over other types of grease gun–the rotary vane nozzle. This nozzle, attached to the bottom of the unit, has a wide, oval-shaped intake that allows a steady stream of air to be passed through it. Because the intake does not move, there is no turbulence, so the pump/rubber remains securely seated in place. The intake is also wide enough to accommodate a wide variety of standard grease fittings. Some models can also accept interchangeable fittings, allowing you to use one for a different application than you originally purchased it for.
The pump, on the other hand, serves the same purpose as the rotary vane cleaning device. However, its application is much smaller and confined to a very narrow area. This allows for a quick and easy clean up of grease fittings without worrying about cross-contamination or damaging surfaces. It also eliminates the need to remove the lubricant from the receiving area before it can be pumped into the appropriate areas.
So how do you know if you need a new grease gun? Most new grease cartridges are sold as single-use items. Meaning that they are only good for one pumping cycle. This is because the grease gun reservoir (which holds the lubricant) must be empty before a new cartridge can be used. As such, most new grease guns will only last one pumping cycle before needing to be replaced.
So how do you load a grease gun correctly? In general, place the nozzle of your tool over the top of the receiving area. Then, using an open container tip, pump the cylinder to fill the receiving area with greasy paste. Once completed, release the valve and allow the valve to fill the container back up with the excess paste. This process should occur multiple times before the container needs to be refilled again.