Difference Between Piston and Plunger

With the current modern lifestyle, high pressure, as well as low pressure applications, are a necessity. There are various applications used, among the most common are piston and plunger. Although both operate as positive reciprocating displacement, they are different in various ways.

What is Piston?

This is a component of gas compressors, reciprocating engines, pneumatic cylinders, reciprocating pumps, and other similar mechanisms, and is the moving component in a cylinder. It has various functions, depending on the component. For instance, a piston transfers force to the crankshaft to the expanding gas in the cylinder through a connecting /piston rod in an engine. The function is, however, reversed in a pump whereby a piston covers or uncovers ports in the cylinder hence acting as a valve. Types of pistons include trunk pistons, crosshead pistons, slipper pistons, deflector pistons, racing pistons, and piston pumps, just to mention a few.

What is Plunger?

Made out of a rubber suction cup that is attached to a wooden or plastic stick, a plunger is a device used to unblock pipes and drains. Most effective with water in the drain, plungers work by forcing air into the drain or pipe hence breaking up or loosening the blockage. Different shapes of plungers exist depending on the intended use. For instance, a kitchen plunger is different from a bathroom plunger. 

Similarities between Piston and Plunger

• Both operate as a positive reciprocating displacement

Differences between Piston and Plunger

Definition

A piston is a component of gas compressors, reciprocating engines, pneumatic cylinders, reciprocating pumps, and other similar mechanisms, and is the moving component in a cylinder. On the other hand, a plunger is a device used to unblock pipes and drains and is made out of a rubber suction cup that is attached to a wooden or plastic stick.

Function

A piston has different functions depending on the component. For instance, it transfers force to the crankshaft to the expanding gas in the cylinder through a connecting or piston rod in an engine. The function is, however, reversed in a pump whereby a piston covers or uncovers ports in the cylinder hence acting as a valve. On the other hand, a plunger clears blockages in pipes and drains by forcing air into the drain or pipe hence breaking up or loosening the blockage.

Material

While the piston is made of cast iron, the plunger is made out of a rubber suction cup attached to a wooden or plastic stick.

Piston vs. Plunger: Comparison Table

Summary of Piston vs. Plunger

Made of cast iron, a piston is a component of gas compressors, reciprocating engines, pneumatic cylinders, reciprocating pumps, and other similar mechanisms, and is the moving component in a cylinder. On the contrary, a plunger is a device used to unblock pipes and drains and is made out of a rubber suction cup that is attached to a wooden or plastic stick.

Sharing is caring!