In the world of control valves, there are numerous designs that will successfully modulate the flow of clean fluids. However, if the fluid contains solids, the scenario becomes more challenging. These ‘clean fluid’ valves are not a viable option for slurry duty, as their complex flow paths can erode or become plugged very quickly.
End users needing to modulate the flow of abrasive slurry must select alternative valves with simple ‘line of sight’ trim geometry, such as ball valves, butterfly valves and pinch valves. These designs provide relatively little flow re-direction and minimal interference with the abrasive slurry.
The downside to typical ‘line of sight’ valves is that fluid velocity through their restricted opening is much greater. This increases the rate of erosion and the valve’s susceptibility to cavitation, resulting in frequent valve replacements, pipe erosion, damage to ancillary equipment, down time and labour costs.