How Thermal Spray Coating on a Pump can Eliminate Cavitation

Understanding How Thermal Spray May Reduce or Mitigate Cavitation in Pumps

Can Cavitation Be Stopped?

The most effective method for reducing cavitation is to let pumps operate at their designed flow rate while keeping in mind the pump’s designed operational curve. It is not always possible to avoid cavitation, and it is often advisable to construct pump housings and impellers out of durable, hard wearing materials.

A pump constructed from tougher, more durable alloys can be significantly more expensive than traditional cast steel or bronze. This cost can be reduced by constructing the pump and its parts from conventional materials but lining the interior fluid handling surfaces with cavitation resistant thermal sprayed coatings..

Cavitation constantly threatens a pump's durability because it can be difficult to detect while the pump is running, and, once it begins, the erosion caused by cavitation can quickly accelerate. If cavitation is identified to be a problem, a protective coating on the anticipated affected areas of new components can substantially delay the initiation of erosive wear.

How Does Thermal Spray Help?

Thermal spraying is a process for applying thin metallic or ceramic coatings to metal components in a manner similar to spray painting; any surface that is accessible by line of sight can be coated. Some metallic coating alloys are especially resistant to the action of cavitation, and thin coatings of these materials on cavitation-prone areas of the pump interior can effectively reduce or eliminate the action of cavitation erosion without affecting pump performance.

These coatings are useful both for protecting new pump components intended for use in applications where cavitation has been a problem, and also for rebuilding and restoring pump parts that have previously been damaged by cavitation.

The actual efficacy of commonly applied cavitation resistant coatings is dependent upon several factors, including the design of the particular pump being coated and the fluid it is handling. In practice, however, coated pump components can extend the operational life of a pump and its performance by multiples. Coating chemistry and hardness can also be selected for optimum performance in a specific application. 

The most common coatings for cavitation resistance are HVOF-applied superalloys and carbides. Their exceptional density and high bond strength make them especially resilient against the action of cavitation erosion. HVAF coatings and some ceramics can offer even greater protection for some applications, depending on pump design and operating parameters and the fluid being conveyed.

Thermal Spray Coatings Can Protect and Extend the Life of Your Pumps

Thermal spray coating can be an effective means of eliminating cavitation in pumps. By creating a smooth, uniform, hard surface on the pump impeller and/or housing, cavitation and the resulting damage to the pump can be reduced or eliminated. Thermal spray coating can also extend the pump's life by protecting fluid handling surfaces from wear and tear. For this reason, investing in this treatment can save operators significantly in maintenance and repair costs in the long term.

Hayden Corporation has been in the  thermal spray coating industry for over 100 years, and our team of experts can help you find the best coating solution for your needs. Thermal spray coatings, such as HVOF coatings, are among the many options we provide, and our team is here to assist you in identifying the best one for your purposes. Inquire about our thermal spray services today!