The sawing machine swallows the log and turns it into boards, planks and wood chips. It is the heart of the sawmill, inside of which runs the Veisto-developed power unit consisting of a gear pump based on speed control, a SynRM motor and a frequency converter.
The development of the power unit began 1.5 years ago, and the test device proved to be a promising concept. In May 2022, the first unit was delivered to Rauma’s new state-of-the-art sawmill.
“Initially, the first goal was reducing the noise level, but also of course improving the performance and operational reliability,” says Veisto’s technical expert Leo Ukkonen.
Speed control based pump
Unlike old variable displacement pumps, the power unit pump developed by Veisto is only rotated when the flow rate is needed, which produces less heat and thus operates with a higher efficiency. The new unit is also more dynamic.
”And when the speed is taken directly from the speed of the movable actuator, the delay remains minimal, and it may be that even more performance can be obtained,” considers Ukkonen. He also praises the equipment delivered by ABB, which enables energy savings. “The pump itself is simple technology, and the motor and the frequency converter take care of energy efficiency. SynRM is the thing.”
ABB’s SynRM motors have an excellent, even IE5 energy efficiency rating, and their energy loss is as much as 40 percent lower than that of commonly used IE3 motors. Furthermore, SynRM motors are more energy efficient and therefore produce less carbon dioxide emissions worldwide.
Lower need for cooling
Although the energy efficiency of the power unit has not yet been measured, the efficiency can already be seen: the new system has a clearly lower requirement for oil cooling.
“The smaller need for cooling is a selling point, especially in trade with warm countries. Today, everybody is constantly concerned with energy efficiency,” says Ukkonen. Out of Veisto’s total number of exports, 80 percent are primarily to North America and Central Europe.
Generally, Ukkonen feels that the biggest energy saving potential is in hydraulics. “It has been working with poor efficiency, which means that about 30% of the energy is wasted. Now this can be overcome.”
For Veisto, there is no going back, and according to Ukkonen, the family business will use new pump technology in the future. In addition to energy efficiency, the pump’s lower noise level increases well-being at work and gives more opportunities to place the machine in production facilities. “The customer trusts the technology we produce, which means this will be preferred in 80-90 percent of orders.”