Energy efficiency in industry and production

Using metal-cutting fluids in an energy-efficient manner

Case Study BOSCH metal cutting
A company-wide analysis of Bosch has found metal cutting to be one of the most energy-intensive production processes. Together with our locations in Feuerbach and Bamberg, Bosch Rexroth and the Central Department for Production Engineering, we were able to identify that the supply of cutting fluid often exceeds 50% of the machining centre and grinding machines’ energy requirements – it is therefore the main energy consumer.

Use of optimised cutting fluid nozzles for grinding

We were able to develop and implement the following economic measures:

Reducing demand
Largely abandoning the use of cutting fluid (e.g. minimum quantity lubrication) is unfortunately not a possibility for us due to quality-related issues. However, we achieve good results by optimising spray nozzles for grinding and by reducing the cutting fluid pressure for internally cooled drilling and milling tools.

Shutdown during downtime
Usually, the cutting fluid supply continues during off hours so that the machine can maintain a steady temperature. The machine is therefore extensively flooded with cutting fluid. By optimising the restart process and improving scheduling, we have made temporary shutdowns possible.

Temperature increase
When there are large temperature differences between the cutting fluid and its surroundings, the cost of the re-cooling process increases significantly. With oil-based cutting fluids, we can often adjust the temperature to the room or track it.

Pump control
Larger pumps are especially used in central systems and to internally cooled tools. The pressure is usually kept constant by a lossy bypass regulator. Regulating the pump speed instead provides significant savings.

Realised savings
We recently launched the global rollout of the proposed measures. To this point, we have been able to account for a total savings of 4,000 MWh per year. This is equivalent to the electricity needs of 1,000 single-family houses.

contact details/company:
Robert Bosch GmbH
Diesel Systems
Wernerstr. 51
70469 Stuttgart-Feuerbach

contact person:
Steffen Behnke
+49 (0) 711 811-30379