Optimisation of energy consumption on CNC lathe

Rising electricity prices mean that optimizing energy consumption in CNC lathes can yield huge savings for companies, increasing their competitiveness in the market. The comprehensive approach to optimizing energy consumption when working on FAT lathes covers key areas such as:

• the use of modern, energy-saving technologies
• selection of the right CNC machine and modern cutting tools
• proper maintenance and inspection of CNC machines

Intelligent energy management systems in CNC lathes

Modern machine tools equipped with advanced drive systems, energy management systems and other energy-efficient solutions can significantly reduce the consumption of electricity compared to older models. Over the years, the technology of the drives used has changed diametrically. The kinetic energy stored in the main spindle is no longer converted into heat (in the resistor) during braking of the workpiece mass but is transferred back to the power grid. With multiple acceleration and braking cycles, this has a significant impact on the energy efficiency of the lathe.

The following features of the SINAMICS family of drives implemented by FAT HACO stand out:

1. In ECO mode, the motor operating point in the partial load range is automatically adjusted and optimized. This reduces motor losses, for example on machines that do not require high torque across the entire working area.
2. With bypass mode, the inverter can be electrically bridged when the motor is working, often in the range of rated speed. This helps to avoid losses on the inverter.
3. Passive power compensation. The use of SINAMICS inverters with Active Line modules reduces the capacitive and/or inductive passive power in the machine. This saves on expensive passive power compensation systems.
4. Kinetic energy buffering. In the case of dynamic conversion in single- and multi-axis systems, the kinetic energy contained in the system is reused. A motor connected to a common intermediate circuit is used to buffer kinetic energy.
5. Electricity buffering. In the case of dynamic reversal in single- and multi-axis systems, the kinetic energy contained in the system is reused. A capacitor module connected to a common intermediate circuit is used for electricity buffering.
6. Optimized Pulse Patterns. SINAMICS S is ideally suited to SIMOTICS motors and SIMOGEAR motoreducers by optimizing frequency and pulse patterns. Benefits: Optimize system performance, reduce system losses, reduce temperature and noise.
7. Energy feedback. In conventional drive systems, braking energy is converted into heat via braking resistors. The SINAMICS G and SINAMICS S inverters do not require braking resistors and transmit braking energy back to the power grid.
8. While working, you can perform an analysis of your energy consumption using the energy saving meter. The energy saved accumulated during working hours is compared with the application with a constant rotational speed.

Choosing the right CNC lathe

To ensure a less energy-intensive unit, it is also important to select the right machine, components and tools for the type of machining we are dealing with in our plant.

When planning to machining heavy, long parts, it is worth considering an investment in a four-guideways lathe - TUR 4MN. Its support with tool head, mounted on the two front guides, allows you to bypass steady-rests and tailstock without collision, thus eliminating the downtime and retooling of the machine. The machine can also be equipped with a tool magazine and automatic changer, which will certainly speed up the production organization. However, it should be remembered that if the tools in the magazine have not been sorted for a specific production order, then the tool replacement time is very long, and this results in energy consumption that can be avoided.

The TUR 4MN lathes, adapted for machining (turning, milling, drilling, grinding) really large parts, can generate significant amounts of chips. Our solution with double chip conveyor controlled in pulsation mode instead of continuous mode ensures that the machine is kept in better condition even during long turning or milling operations. The lathe's operator can focus on the machining without interrupting the machine's operation. The second conveyor allows to effectively remove residual material from the work area, and the programmed stops of the chip conveyor allow cooling to be drained from the chips.

When you need a machine adapted for complex operations in multiple axes, not limited by the support sled, it is worth choosing a lathe with slant bed from the FCT or FCTS series.? From the perspective of electricity consumption, CNC machines should be used with the shortest possible downtime. The solution in the form of two independent supports enables external and internal machining without causing downtime in production.

The following solutions used in FAT HACO machines also have an impact on the energy consumption of the machine tools:

• LED working area lighting instead of halogens
• Auxiliary motors have efficiency class IE3 (chip conveyor, cooling pump)
• 24VDC electronic impulse power supply instead of transformer-rectifier system
• Automatic screen eraser in control panel
• Cooling pump can be optionally controlled by inverter
• Intermittent main motor fan control

Maintenance and service of CNC lathes

Regular maintenance and ongoing diagnostics of the technical condition of CNC machines have a direct impact on their energy efficiency.

Clean and properly lubricated drive bolts and gears guarantee optimum electricity consumption, reducing friction.

Optionally, the machine tool can be equipped with a system for monitoring the basic parameters of the power supply network and the electricity meter connected to the Ethernet network gives the possibility of remote diagnostics and viewing the history of power consumption.

Having in the database, information about the machine tool from previous months and even years, allows you to plan repairs, calculate the efficiency ratio or analyze the energy consumption by the machine in selected periods.

The development of innovative technologies in FAT HACO lathes creates new possibilities for further optimization of energy consumption in CNC machining. Actions such as adjusting cutting parameters, monitoring and analysis of energy consumption and proper maintenance of equipment can reduce production costs and open up new perspectives for a more sustainable, economical operating model.

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