Component vs Cartridge Seals: How to Choose


Mechanical seals are an integral part of machines that deal with hydraulics, pumps being an excellent example. Since there are different types of seals available, however, choosing the one that would work best for your pump can get tricky.

This guide will help you choose between the two most common types of seals, component and cartridge, by detailing their use cases, pros, and cons.

What are Component Mechanical Seals?

john-crane-aura-120-gas-seal-narrow-section-300x300A component mechanical seal comes as a set of components that you must assemble before installing. Hence, the process requires skilled service technicians. When you order a component mechanical seal, you will receive several parts in a package like seal faces, O-rings, boots, etc. Since you, as a customer, take care of the assembly process, component mechanical seals are the affordable option among the two and are also easier to service.

Pros of component seals

  • Component mechanical seals cost less than cartridge seals
  • These seals are the most common and widely available for different pump models

Cons of component seals

  • Installing these seals is a complex process and requires a skilled technician
  • Inaccurate spring tension on seal faces often causes the seal to fail

What are Cartridge Mechanical Seals?

john-crane-mechanicial-seal-bellows-Type-5611QCartridge mechanical seals come pre-assembled from the factory. Hence, there is no need for a service professional to assemble or calibrate the seal before installation. Furthermore, since the part comes pre-assembled and tested by the manufacturer, the leeway for errors is significantly low.

Pros of cartridge seals

  • Easy installation, no assembly required
  • These seals have low chances of failure

Cons of cartridge seals

  • Cartridge mechanical seals can cost two to three times the price of component seals
  • These seals are available only for specific pump types

Choosing between Component and Cartridge Seals

Choosing between the two types of mechanical seals comes down to certain key factors.


Cost is a major part of any maintenance project. Cartridge-type mechanical seals are much more expensive than component mechanical seals when comparing the two options.

Ease of installation

While both types of seals offer reliable performance once installed correctly, the degree of installation complexity varies significantly based on your choice. Component mechanical seals must be assembled before installation and require spring tension adjustment. This is a task best reserved for skilled technicians. On the contrary, cartridge mechanical seals come assembled. Hence, the installation process is simple and leaves less room for errors.

Parts availability

Cartridge mechanical seals are easy to install when you have the right make and model. However, they still lack compatibility with a broad range of pumps available in the market. Since component mechanical seals have been in the industry for the longest, they are available for almost all types of shafts and pumps.

Not sure which seal will perform best for your pump?

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