Types of Impellers You Need to Know

Centrifugal pumps have a rotating part called the impeller. Its job is to use the energy from the motor to speed up the fluid away from the center of rotation.

Most of the time, the impeller is a short, open-ended cylinder. This is useful for getting laid in and has a vane to move the fluid in a radial direction.

The impeller is made of metal through a process called casting. There are two main types of metals: those that contain iron and those that do not. Impellers made of FCD (Ferro Casting Ductile) or FC (Ferro Casting) are made of iron (Grey cast iron).

The cost of impellers made of ferrous materials is less than those made of materials that are not ferrous. Most non-ferrous impellers, on the other hand, are made of bronze.

Here are some types of impellers and what makes them unique.

Based on the Shape of the Propeller

When viewed based on the shape of the blades, impellers are divided into three types, including:

Open Impeller

Types of Impellers

An open impeller has vanes attached to the middle but does not have walls on the sides. This impeller is often used to pump very dirty liquids or have a lot of sludge in them.

An open impeller tends to be weaker because it is not protected by a shield and has no support on either side. Most small pumps that don’t have to work under pressure use impellers like these.

Semi-Open Impeller

Types of Impellers

A semi-open impeller is a type of impeller that has a vane attached to one of its walls. This impeller is often used to pump fluids with low levels of contamination and slurries that are not as thick.

This impeller has a wall sheath on the back that can give the vanes more mechanical strength. The other side is open.

The semi-open impeller works best in medium-sized centrifugal pumps that move small amounts of soft solids.

Closed Impeller

Types of Impellers

Closed impellers are those that have vanes that are closed on both sides. Because of this, the impeller is stronger than other types of impellers.

This impeller is thought to be the most efficient and is often used to pump clean liquids or liquids with only a tiny amount of dirt in them.

Because it needs close-range wear rings, a pump with a closed impeller usually has a more complicated design and is more expensive.

This lowers the axial load and keeps the pump working well.

Based on the Amount of Incoming Fluid

Types of Impellers

When viewed from the amount of fluid that enters, impellers can be divided into two types, including:

  • Impeller Single Suction: The single-suction impeller only lets liquid flow into the center of the vane from one direction.
  • Impeller Double Suction: A double-suction impeller lets fluid enter the center of the vane from both sides simultaneously.

Based on The Flow

Types of Impellers

When viewed based on the flow, impellers are divided into three types, namely:

  • Axial Flow Impeller, i.e., the impeller moves the liquid parallel to the impeller.
  • Radial Flow Impeller, i.e., an impeller that transfers fluid at right angles to the impeller itself.
  • Mixed Flow Impeller, specifically, the impeller, which has both axial and radial flow characteristics. This impeller can move material from different angles of right-angle radial flow.

So, that’s what you need to know about the different types of impellers. We hope that the above information can help.