Many industrial cleaning jobs require pumps that provide a little more power. The HDP 500 Vario from Hammelmann utilizes a three-speed gear drive to effectively extend application areas in those industrial services.

The high-pressure pump unit offers an electro-pneumatically switchable three-speed gearbox between the drive motor and the pump that allows the flow rate to be influenced in a much wider range than previous models. The improved flow rate control extends the unit’s field of application and opens up new applications in industrial cleaning.

“Conventional high-pressure units offer limited control of the flow rate via the engine speed, in which the engine speed influences the delivery rate in a nearly linear manner,” explains Denny Mesarvey, sales manager for Hammelmann. “Excess volume is discharged — unused as hot water — via an additional splitting nozzle or recycled into the buffer tank.”

The control of the flow rate becomes more precise and variable with the unit’s gear drive. The highest gear uses the full power the unit is designed for. An HDP 502 Vario with a 2-inch-diameter piston and an engine speed of 1,800 rpm, for example, will deliver 15,000 psi at 70 gpm. The available power is suitable for the use of tank cleaning devices and other demanding tasks that require high operating pressure and high delivery volumes. In the middle, second gear, the speed of the pump is halved and thus reduces the flow rate to a maximum of 50 percent. In this mode, the unit runs with parameters suitable for pipe and tube cleaning.

“For working with manually operated spray guns, the pump capacity can be reduced to a flow rate of 7 to 11 gpm at 15,000 psi in first gear,” Mesarvey says. “This corresponds to approximately one-sixth of the maximum pump capacity. The user gets the amount of water and pressure that is needed for the job, and it is not necessary to reduce or return excess volumes.”

According to Mesarvey, the optimized design reduces the wear of the components of the motor and pump. Maintenance intervals are extended, and downtimes and operating costs are reduced.

Fuel and water consumption are also significantly reduced. While it uses 30 gallons of diesel per hour at full power, that is lowered to 6 or even 4 gallons per hour with reduced engine speed capabilities. 800-783-4935; www.hammelmann.com.