Difference Between Flywheel and Governor (With Table)

Parts of a machine are often confused with each other. Two of such vital pieces include The Flywheel and the Governor. From ancient times when simple machines came into existence. These two components have found uses. However, their names arrived much later. 

A flywheel is a component that, as its name suggests, consists of a wheel. This wheel is then attached to a shaft that rotates. A governor at the same time is a speed limiter and limits this speed by regulating the supply of fuel. So the difference between these two is many. 

Flywheel vs Governor

The difference between flywheel and governor is that a flywheel stores excess energy from rotation and uses it later, but a governor controls the fuel supplied to make the machine work. In simple terms, It includes the different functions, principles, and parts that make up these components. 

A flywheel has a wheel affixed to a shaft. The primary purpose of this device, in simplest terms, is to convert the energy acquired during rotation to the point that causes motion (kinetic energy). Also, it helps to bottle up the excess amount of this energy. It finds uses in the later phases. While controlling speed, it observes that when at the time of rotation and the rate don’t fluctuate.

A governor, on the other hand, is a device to regulate the amount of fuel supplied. This amount depends upon how much load we are dealing with, and the power goes there accordingly. This device helps to make a machine work, keeping the speed constant, unlike the flywheel. They depend upon the principles of centrifugal force. 

Comparison Table Between Flywheel and Governor

Parameters of ComparisonFlywheelGovernor
UseThis device is used to store the excess rotational energy and use it later. This regulates the fuel supply according to the load. 
PrincipleIt uses the principle of inertia.It uses the principle of centrifugal force
Load dependenceIt doesn’t depend on the amount of load.It depends on the amount of load that’s applied.
How speed is affectedIt doesn’t give a constant speed.This gives a constant speed.
WeightIt is a heavy machinery part.It is a light machine part.

What is Flywheel? 

A flywheel comes along with a shaft and wheel. The shaft is like a handle. The principle of this device is just like that of inertia. The inertia further is that quality by which one can know the amount of torque ( force of rotation) applied to move a particular part. From ancient times, it found applications in various devices such as the wheels used for pottery and the spindles. 

The primary function of this device is speed regulation. It is to ensure that during a rotation, the speed doesn’t see any change or fluctuations. The rate doesn’t have to be constant in this case and can be changed. Also, this device stores the excessive energy that comes out during the time of rotation. This rotational energy is kinetic/movement-causing energy. This extreme energy is held to be used at a later point in time. This is independent of the load applied

Unlike the governor, it doesn’t control the fuel. It has nothing to do with the amount of energy. This component has more weight than the governor. The more weight is because this part is significant as the whole movement depends upon it. Flywheels are of three types. These are – rimmed flywheels, followed by shaftless flywheels, and the Super flywheels. Many materials like cast iron, steel, and aluminum can also serve as materials for manufacturing.

What is Governor? 

Governor is a device that helps to keep the speed of the machine constant. It depends upon the amount of load or force that is applied. It regulates the supply of fuel. This regulation is further dependent upon the amount of load put upon the device. It uses the principle of centrifugal force. It consists of a pair of different weights rotating around a spindle driven by the prime mover. The application of force is using springs. This device finds applications where the speed has to be kept the same throughout. 

As the purpose is regulation of speed, this is accomplished by controlling the amount of fuel. The fuel that goes into the machine hangs upon the quantity of force (load) put to it. This device is much lighter in weight than the flywheels. They find uses in places where speed has to be consistent in turbines and engines and generators.  From the sixteen hundreds (the 1600s), it found utilization in windmills. 

Also known as a speed limiter, this device has been performing well even at present. It is divided into three major categories, namely pneumatic, followed by electronic, and finally the centrifugal governor. These parts are very cost-effective and easy to make, and they are used.  Also, they respond very well to load changes upon making some evolutions, enhancing their accuracy.

Main Differences Between Flywheel and Governor

  1. Flywheels find uses in storing the energy acquired during a rotational motion to be used later. However, governors help in supplying fuel as per the load given. 
  2. The flywheels use the principle of inertia. On the other hand, governors use the direction of centrifugal force. 
  3. The flywheels do not depend upon the amount of load. However, a governor is dependent on the bag. 
  4. A flywheel doesn’t ensure the speed to be constant throughout. However, in a governor, the rate is consistent throughout.
  5. The flywheels are generally heavier in weight. However, the governor is light in weight.


At present, when machines are getting more and more developed, these two parts, namely the governor and conductor, have had some evolutions. These have enabled them to be used in a wide range of machines, including various engines, generators, etc. An amalgamation of these two is called the flywheel governor. It serves as both when used in a device by performing activities of both of these components.

While learning mechanical engineering, a knowledge of these two components is essential. They require certain simple parts to be created and act fully functional. These can be further said to be one of the most necessary and critical components that work in a machine. Hence their importance in the field of machinery is deemed eternal.


  1. https://www.sciencedirect.com/science/article/pii/S1007570417300941
  2. https://www.scientific.net/KEM.385-387.309
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