Protect Your Impellers And Casings Against Wear With The Right Repair Coatings

Repair coatings can help protect a company’s bottom line. When parts fail because they were not sufficiently protected, or if they cannot be quickly repaired for extended part life, maintenance costs increase, downtime increases, and replacement costs increase. All of these escalations can wreak havoc on a company’s bottom line.

Thanks to thermal spray coatings however, the life expectancy of casings and impellers can be prolonged.

Pump Impeller Corrosion, Cavitation, And Abrasive Wear

Silt, sand, and other abrasive substances are frequently contained in the media that flows through pumps. These substances end up going through close running clearances, the sidewalls of impellers, and through all fluid channels. The most abrasive wear can occur on narrow labyrinths and other areas with high flow velocities. These particles (silt, sand, etc.) can impact the wall at a shallow angle if they are less than the labyrinth’s clearance. As they move freely through the pump, erosive wear results.

The particles can jam between the two walls however, if they are of the same size as the close running clearances. What results here is severe three body abrasion (two walls and the abrasive particle add up to three bodies).

Dramatically increased wear rates will result from unfortunate circumstances such as erosion, cavitation, and the combined effects of both with other corrosive media.

Protecting The Parts of Centrifugal Pumps Against Wear

With the right surface treatment, protection against the aforementioned wear and tear can be achieved on centrifugal pump parts. Detonation, HVAF, HVOF, and other high velocity technologies can be used to deposit extremely wear resistant carbide coatings.

The particular pump coating application needed is assessed by the use of major factors such as a thermal spray coating’s behavior against the particular type of corrosion and erosion occurring or expected to occur.

At all angles of impingement, tungsten carbide coatings are tough and wear resistant enough to protect impeller base metal and other substrates. Certain powders provide adequate corrosion resistance and the highest wear resistance in most environments. With the proper thermal spray coating, both new and repair applications can be applied to various impeller and case rings. This will increase their lifespan exponentially.

The Benefits of HVAF

Though many thermal spray coatings are available using numerous methods, HVAF thermal spray systems are beneficial for the following reasons:

• Gain a competitive edge for your company in both quality and cost.
• Achieve cavitation and nonporous abrasion resistant, high hardness characteristics through high-quality coatings applied by HVAF ultra mode.
• Use HVAF economy mode to lower costs but achieve HVOF quality.

Though thermal spraying can be achieved by a technician hand spraying pump impellers and other parts of machinery, mechanical or robotic methods are frequently used in this operation. The coating result is uniform, and the process is extremely fast. Compared to manual blasting, it also consumes less grit and is far more accurate.

The folks at A & A Coatings are familiar with every type of thermal spray coating and process available today. We work with numerous industries to protect their bottom line by decreasing maintenance costs, downtime, and replacement costs. If you would like to discuss which coating would best suit your needs, talk to one of our knowledgeable representatives today.