Anatomy of a Grease Gun and its Types

The lever is used in manual configurations of the grease gun for hand-pumping the grease from the barrel to the hose or tube.

The trigger and handle are used in manual configurations of the grease gun for hand-pumping the grease from the barrel to the hose or tube in a similar way as the lever.

The barrel is the exoskeleton of the grease gun that houses either the grease tube or the grease supplied from bulk storage.

The grease tube (or cartridge) is an inserted housing of grease that is replaceable when grease is depleted.

The hydraulic coupler (or connector) is the connection point that holds the hose or fixed tube attached to the head of the grease gun.

The head of the grease gun contains grease pathways and valves that allow the pumping of grease to travel from the barrel into the flexible hose or fixed tube.

The filler nipple is the injection point for grease from a filler pump.

The air-release nipple allows air to escape after new grease has been added to the grease gun and pumped into the head.

The spring provides the pressure onto the plunger.

The follower rod (piston rod, barrel rod, plunger rod) helps the plunger follow a uniform path as it keeps pressure on the bottom end of the grease tube. It also acts in pulling back the spring prior to inserting a new grease tube.

The follower handle offers a grip when pulling the follower rod prior to inserting a new grease tube.

The plunger provides uniform pressure to the back end of the grease tube as grease is depleted.

The flexible hose is used interchangeably with a fixed tube for flexible positioning of the connector or coupler.

The fixed tube is a rigid form of a flexible hose.

Types of Grease Guns

Grease guns have three ways in which they can be powered: by hand, air or electricity. Aside from these variations, the hand-powered (or manual) grease guns can either be manufactured with a lever or a pistol grip. The benefits to each of these depend primarily on the intended application and the lubrication technician’s personal preference. One other major variation to the grease gun is how the grease is to be loaded: by suction fill, cartridge or bulk.

Manual (Lever) – This is the most common type of grease gun and can supply around 1.28 grams of grease per pump, which is forced through an aperture from hand pumps.

Manual (Pistol Grip) – This variation of the lever-type grease gun allows for the one-handed pumping method, which is very common. It provides approximately 0.86 grams per pump.

Pneumatic (Pistol Grip) – This grease gun uses compressed air directed into the gun by a hose activating a positive displacement with each trigger.

Battery (Pistol Grip) – This is a low-voltage, battery-powered grease gun that works comparably to the pneumatic grease gun. It offers the advantage of being cordless.

It’s fundamental that grease is used as a lubricant because it clings to a machine’s moving surfaces without easily leaking away like oil. For this reason, the filling and refilling of grease in grease-lubricated machines must be treated differently than that of oil-lubricated machines. Therefore, it is essential that the proper grease gun operation is understood and managed by for bearing and machine reliability. Simply knowing the signs of overgreasing and undergreasing and how often to reapply can go a long way in extending machinery life.