Energy-saving air blowers manufactured with the help of green machine tools

There is an unusual parallel between a new, low-pressure air compressor (blower) manufactured by entrepreneurial British firm Lontra  and the Japanese-built turn-mill centre from Okuma that is used to machine one of Lontra’s fundamental key blower components. Both pieces of equipment have been engineered for maximum environmental sustainability whilst in operation and both harness Industry 4.0 connectivity to make them even more efficient. Okuma’s UK and Ireland sales agent NCMT describes the multi-tasking turn-milling application.

At the core of Lontra’s LP2 Blade Blower is its custom-engineered, patented Blade Compressor® positive displacement technology, a novel rotary piston and cylinder design that delivers oil-free air or gas at up to approximately 1 bar pressure. The custom-engineered LP2 Blade Blower unit is used in many industries including water aeration, where electricity savings of up to 34% have been noted, through to food, pharmaceutical and other pneumatic conveying applications, in which similar energy reductions have been recorded. It is also found in cement manufacture, mining and power generation.

Driven by the remarkable energy savings achieved by the LP2, the global demand for these units has surged, leading the manufacturer to invest £17 million in constructing a state-of-the-art factory in Doncaster dedicated to meeting the increased production volumes.

It is in this facility that the Okuma Multus B550 turn-milling centre has been installed to carry out finish machining operations on the blower rotor, a high-value component critical to LP2 operation. Adrian Pratt, Manufacturing Engineer at Lontra said, “We approached NCMT for a turnkey solution. There are not many factories globally that have the machinery or skillset to manufacture a part like this.

“The Okuma is a very clever, multi-tasking machine that has the size, robustness and technology to machine our large, heavy rotors accurately and repeatably in fewer set-ups. The repeatability aspect is very important, as we need to keep all the rotational parts concentric.

“Multiple features can be machined in one go on the Multus B550, allowing us to meet the high drawing tolerances by avoiding repeated refixturing of the rotor. The rotor production process has been significantly optimised.

“Without this advanced equipment, 10 operations would be required to complete the rotor component. With the aid of Okuma machinery, we have successfully reduced the number of operations by half, further cementing our commitment to lean, smart and sustainable manufacturing practices and continual improvement.”

Speaking of the technological features of the new machine, he referred to the fact that Okuma manufactures its own drives and control system and also develops its own software, which he describes as “second to none”. It means there is one point of accountability for both the mechanical and digital aspects of the machine, a facet of the installation that he values.

Three features of the Okuma in particular help to maintain accuracy of machining. First, the Thermo-Friendly Concept applied to both the machine structure and spindle uses feedback from temperature sensors to ensure high precision machining in a shop floor environment, without the need for a warm-up period. Secondly, multi-axis Auto Tuning periodically and automatically fine-tunes the geometry of the machine before production restarts.

Thirdly, Okuma’s Absoscale linear encoders in the orthogonal axes have industry-leading 0.1-micron resolution for super-precise feedback of axis positions. At the same time, the manufacturer’s 36-million increment rotary encoders provide similar precision in the C-axis axis that positions the powerful 37 kW workpiece spindle and in the B-axis that positions the HSK100 spindle tools.

Greig Underwood, NCMT’s Regional Sales Manager commented, “Being involved with Lontra as they embark on their journey to provide the world’s most efficient blower is exciting and I am looking forward to seeing what we can do next to help them further their goal.

“What interests me about this installation is the alignment between Lontra and Okuma in their commitment to sustainable manufacturing practices, as well as their shared focus on energy-saving designs for their respective product solutions.

“Equally, both companies are leveraging the power of Industry 4.0 to monitor and feed back operational data to optimise parameters and make their equipment even more efficient in real-world conditions.”

Joe Cockcroft, Head of Operations at Lontra concluded, “One of the advantages of building a new factory from scratch is the ability to adjust every detail to make the site as energy-efficient and productive as possible, especially with regard to the machine tools.

“Following significant investment in high-specification capital equipment, we are preparing to build an increasing number of LP2 units to meet market demand. This is scheduled to increase month on month and year on year as our business expands.

“All of this would not have been possible without our hard-working, highly skilled team. We are extremely proud to have great people behind Lontra making this happen.

“Our success is also down to the professionalism of like-minded supplier partners like NCMT. They provided a turnkey package with full engineering support, including training and help with programming and setting up our processes, so rotor production started right first time and without delay.”