Any pump application must consider longevity and cost of replacement when it comes to material selection. There are three key areas that need to considered.

Corrosion: It can be difficult to select the right material that can withstand multiple corrosive factors.  It is also important to factor in conditions of the liquid entering the pump and the corrosive effects of liquid temperature. concentration, pressure and estrained solids.

Abrasion: Metal hardness is a key factor in counteracting abrasive wear, but it’s also important to consider the brittleness of the material being used.

Cavitation: When a liquid is subject to rapid changes of pressure, they can form cavities or voids in the liquid where the pressure is low, and when the liquid is subsequently exposed to high pressure these voids implode resulting in a shock wave that can cause serious damage to a pump.

How to combat?

One way in which to counteract these forms of damage is to use ‘exotic’ and ‘hard’ materials. These consist of materials such an Inconel, Monel, Titanium and Stellite. The issue with these materials is they are expensive to source and to machine. As such, many pump components currently undergo a plating or coating technique to give them further resistance to corrosion and wear.

HVOF is a coating technique that takes powdered material and fires them at a component at high velocities. It is the modern equivalent of ‘metal spraying’ and the key advantage to this process is that it allows you to coat a part with materials like Titanium, Inconel and more. This allows you to use a cheaper base material and get the same attributes as manufacturing in these materials. HVOF coatings also have low porosity and are friendlier to the environment then many plating options.

B&B offer coating for many pump and valve applications and can guide you as the best materials to use in order to counteract the corrosive elements in your application. You can email us on mail@bandbprecision.co.uk or call 01484866386