Newly developed hydraulic drives more energy efficient in use

transfluid technology allows energy savings of up to 70% compared to conventional hydraulic systems

Opinions are usually divided when it comes to which drive is better for tube processing. Electrical drives demonstrate their strengths through precision and especially energy efficiency. Conventional hydraulic drives with their high level of robustness and unique power density have been missing precisely this energy efficiency up to now. Now that has changed with a crucial development by transfluid. This solution-finding company, based in Schmallenberg, has substantially improved the efficiency of hydraulic drives. The high level of energy efficiency is impressive with energy savings of up to 70%. 

“We implement the controls on the hydraulic pumps using servo motors. It is primarily the effective interaction of different technical details that allows the sustainable optimisation. This makes tube processing even more economical”, explains Stefanie Flaeper, Managing Director of transfluid Maschinenbau GmbH. The speed and thus the volume flow of the pump is adapted exactly to the required pressure in the new hydraulic drives from transfluid. The energy losses that are otherwise caused by oil on the pressure valve are thus avoided completely. The speed and thus the volume flow of the pump are also adjusted exactly to the required volume flows. This thus eliminates the flow loss from pressure regulation that is usually the case.

The motor is still as soon as no hydraulic function is active. No heat is produced in the system at this moment. This state is achieved several times, even during an automatic cycle. For example the servo pump is stationary if the mechanical axes, longitudinal feed or rotation on a bending machine are active. This reduces the overall duty cycle of the pump and thus saves energy.

Small motors and pumps - large effect

The size is substantially reduced in comparison to normal three-phase motors because servo motors can be overloaded for a short period with a multiple of the nominal power. This results in lower inertia and improved dynamics. Comparably small pumps are also installed because the servo motor has a wide speed range. These pumps can be driven with up to 3,000 rpm. This keeps the inertia of the pump low.

Without refrigeration and with low noise emissions

The high level of energy efficiency means that refrigeration is not normally necessary. This reduces the energy consumption of the cooler and also eliminates the dust that is otherwise raised by a fan propeller. There is no noise from a fan and also no cooling fins that need cleaning. 

transfluid uses quiet internal gear pumps for noise reduction. There is no flow-generated noise from throttle valves and delivery valves and there is absolute silence in stand-by operation because the pump is stopped and there is no noise from the cooler. transfluid can realise a hydraulic system with an output of approx. 55 l/min and a high operating cycle of different volume flows with a noise level of less than 75 dBA.

Reduce operating costs - an example

The hydraulic bending machine DB 2076 3A-CNC by transfluid has a hydraulic aggregate with an output of approx. 60 l/min and an operating pressure of a maximum of 200 bar. This requires a 15 kW drive with a conventional design. Approximately 80 % of the drive power is demanded on average because normal motors also have a high power requirement when idle. With six hours of daily use this results in annual power consumption of 15,840 kWh. In a typical bend cycle with interval times of 5 s to remove and load the tubes a servo pump has an average power consumption of less than 4 kW, which corresponds to annual consumption of 5,280 kWh. If one kilowatt hour costs 0.25 Euros then this application of the technology already saves power costs of 2,640 Euros per year.

We can then add a reduction in maintenance and repair costs because of the simplified fan technology to this total. It is usually possible to completely forego throttle and pressure valves. Pressure switches to poll the axes are also no longer necessary and are replaced by a central pressure sensor.

Convenient controls

The pressure on all axes can be regulated and the speed of all hydraulic axes easily set using a touch panel. The positioning of the axis is possible with an accuracy of 0.05 mm as long as a position sensor is integrated (optional). It is sometimes even possible to forego control with an expensive control valve and all the control electronics. The price of the HNC axis is thus reduced. The prices of the conventional hydraulics and the servo pump are almost identical. Thus the sustainable efficiency pays off from the very first use.


transfluid Maschinenbau GmbH
transfluid is sought after worldwide as a partner for manufacturing tube bending machines and tube processing machines. Since 1988 transfluid has been further developing its technologies for tube machining, so that it can provide customer-oriented, tailor-made solutions – for plant and machine construction, the automotive and energy industries, shipbuilding and medical device manufacturing. As a world-renowned brand, the company from Germany is present in Europe and with its subsidiaries in Asia.


Stefan Köhler