The rugged construction and extra-thick pump casing of Gorman-Rupp Ramparts air driven diaphragm pumps stand up to the abuses of the most demanding sludge and slurry applications. They overcome the "high-wear" problem commonly found in double diaphragm and progressive cavity pumps. Ramparts pumps are capable of operating dry, on suction lifts up to 20 feet (6.5 m) and handling high solids content up to 70 percent. Pump stroke rate, discharge stroke time, suction drive pressure and discharge drive pressure can all be adjusted independently. Pumps will easily handle heavy sludges at their rate of accumulation in clarifiers and settling tanks. They are also an excellent choice for filter press feed systems.