Mechanical Seal Guide: Types and Components

Mechanical seals are one of the most common sealing alternatives. It helps to prevent leakage, maintain pressure, and avoid contamination. There are different types of mechanical seals serving different purposes with different components. Here are some types of mechanical seals, along with some common seal components you should know about.

Types of Mechanical Seals

Following are the three most common types of seals:

Cartridge Seals

A cartridge seal is a self-contained system that has hardware, a gland, and a sleeve. It allows the unit to be preassembled by the manufacturer, reducing improper seal installation risks. You can find both single and double cartridge seals for your operations.

Component Seals

A component seal consists of two major components: a rotating member and a stationary seat. Unlike cartridge seals, component seals aren’t preset. Therefore, the installation and maintenance of these seals is way more complicated. You’ll have to hire an experienced mechanical seal expert to properly install it for you.

Air Seals

They’re pneumatic and non-contacting. These are especially used to seal the rotating shafts of the pump. They’re installed in slurry and dry powder pumps and help prevent emission, contamination, and product loss by using air or inert gas.

Mechanical seal components

Common Parts of a Mechanical Seal

Following are some of the most important parts of a mechanical seal:

Rotating Primary Face

The rotating primary seal face is connected to the shaft and rotates with it against the stationary primary face.

Stationary Primary Face

The stationary primary face is attached to the stationary housing of the pump or the mixer. It seals the rotating primary sealing element.

Mechanical Loading Device

This can consist of single, double, waves, or bellow springs.

Static of Dynamic Secondary Seals

It seals between the mechanical seal and the shaft.

Drive Mechanisms

This helps with the rotation of the rotating primary seal.


Although these are the most used types of seals and their parts, you may find some other distinctions in types of seals as well, such as balanced and non-balanced, pusher and non-pusher, and conventional seals. However, this is a topic for some other day.

To learn more about mechanical seals, check out Robco of America’s blogs and other resources. We’re a mechanical seals company that offers the best-engineered sealing solutions. For all kinds of mechanical seals and services, call 1-800-662-0585.

Leave a Comment

Your email address will not be published. Required fields are marked *