Why Are Grease Lubrication Pumps Usually Plunger Pumps?

In the field of industrial lubrication, grease plays a key role in ensuring the smooth operation of mechanical equipment. Grease transfer pumps are also essential for the efficient handling of grease.

Grease is typically made by mixing mineral oil with metal soaps, such as sodium or calcium. Its texture can vary widely, ranging from smooth and buttery to fibrous or even rubber-like. These variations in texture affect the grease’s flow characteristics and how it interacts with equipment. Therefore, when grease is too viscous to flow, it must be forced out little by little under high pressure.

The reciprocating motion of a plunger pump can pressurize grease to 10–40 MPa. With a tight fit between the plunger and the cylinder, internal leakage in the high-pressure chamber is minimized, enabling stable grease delivery.

When handling grease, it is crucial to maintain positive pressure at the pump’s suction end to ensure stable flow. This is usually achieved by using a follower plate in the supply tank.

Many users of pneumatic lithium-based grease filling equipment encounter a tricky problem: after the lithium-based grease has been used up, the pressure plate presses tightly against the bottom of the drum, creating a vacuum and forming a strong suction seal that requires two people to pry it apart. The FABIT 64600 lubricant filling kits machine cleverly solves the drum-bottom vacuum suction problem found in traditional lithium-based grease machines. The machine is equipped with its own venting structure. After the lithium-based grease has been used up, a small amount of air can be introduced to separate the pressure plate from the drum bottom, break the vacuum, and allow a single operator to easily lift the plate, making grease replacement more convenient.