A supplier of quarried limestone products are using a fail safe normally closed Pinch Valve from AKO within their sludge application. The Pinch Valve is size DN200, pictured in orange below (product code OV200-03-30-PA2)
Sludge is a residual semi-solid by-product left from industrial or refining processes. It is a separated solid suspended in a liquid, typically containing major quantities of water between its solid particles.
Since sludge can be a fairly abrasive media, the Pinch Valve is an ideal solution for efficient flow control, due to its high resilience elastomer sleeve which opens and closes to control the flow. The rubber sleeve does not trap or clog any sludge, unlike gate valves and butterfly valves.