Energy-Saving Pump Design for Hydraulic Applications with the Sinamics Servo Pump from Siemens

This means that, unlike in a conventional hydraulic solution, complex control systems are unnecessary and energy consumption is reduced by more than half.

Maximum energy efficiency and a compact design are also becoming increasingly important criteria when improving machines with hydraulically driven shafts. With this in mind, Siemens is introducing an innovative speed-controlled fixed-displacement pump for use in e.g. injection molding machines, machine tools or presses.

In the Sinamics solution, a hydraulic pump is driven by a variable-speed servo motor. The oil pressure in the system is controlled directly via the connected Sinamics S120 drive system. As opposed to a conventional application, complex hydraulic components such as variable-speed pumps and valves are unnecessary. Oil tanks can be reduced in size. The cooling system for the hydraulic oil is reduced to a minimum. This innovative concept results in a reduction in energy consumption of maybe 50 to 70 percent, thanks to improved efficiency in relation to an induction motor with a variable displacement pump. The minimal space requirement means that integration into the machine is made easier. Furthermore, there is a reduction in the quantity of hydraulic oil required. For example, for a 60 tonne injection molding machine, working 250 days a year with an active power of 5.4 kW, energy consumption is reduced by around 65 percent compared to the amount needed by an induction motor with a vane pump. This corresponds to a saving of more than 7000 Euros per year.