Kaeser Compressors Australia assisted Wilson Transformer Company (WTC) in meeting the increased demand for compressed air at its new state-of-the-art facility, while optimising the energy efficiency, with the installation of six CSD-series rotary screw compressors.

Manufacturing in Victoria since 1933, WTC has grown steadily to become the largest Australian manufacturer of power and distribution transformers by investing in people, technology and assets. At its four-hectare head office in Glen Waverley, Melbourne, the Power Business Unit designs, engineers, manufactures and tests a range of quality power transformers including generator, substation and auto transformers up to 550MVA and 400kV. Over the past five years, the company has committed major resources into developing its power and distribution transformer capability. A major expansion of its Glen Waverley facility included upgrading the compressed air system.

“In planning the expansion of our production facility it became apparent that our existing compressor station was not going to be able to meet the new compressed air demand,” says Alan Veitch, Improvement Manager for the Power Business Unit at WTC. “The ageing system was also becoming increasingly inefficient and costly to operate. The expansion therefore presented us with the ideal opportunity to address this issue at the same time.”

The plant incorporates two main workshop areas: one for the electrical operations of core cutting, insulation preparation, coil winding, control wiring, transformer assembly, processing and testing; and the other to handle the mechanical operations, which include fabrication, welding, grit blasting and painting.

Compressed air is used to power a number of operations across the two workshop areas, from breathing air used in the blasting facility, to general-purpose pneumatic control systems on, for example, the drying ovens and oiling systems. The biggest requirement for compressed air in planning the upgrade, however, was the introduction of air skates. Powered by compressed air, air skates can lift and move heavy-loads on a cushion of air.

As Veitch explains: “We wanted to introduce air skates into the facility in order to lift and manoeuvre the largest transformers into restricted access areas such as the testing bays where the cranes cannot go.”

To meet the increased compressed air demand and ensure optimum energy efficiency, WTC chose to invest in six Kaeser rotary screw compressors: four CSD T models with integrated refrigeration dryers, and two CSD(X) T SFC variable-speed drive models. Kaeser’s CSD series of rotary screw compressors are available with drive powers up to 90kW producing free air deliveries from 1.07 up to 16.16 cubic metres per minute.

“We primarily chose these compressors because Kaeser is well known for manufacturing high-quality, reliable and efficient compressor solutions,” says Veitch. “And, one of the reasons we were aware of this is because Kaeser was one of our customers and we had in fact supplied them with a Wilson Transformer some years earlier!”

The CSD(X) T series delivers premium-quality compressed air and superior efficiency. At the heart of every CSD(X) T rotary screw compressor lies a low-speed Sigma Profile airend equipped with flow-optimised rotors. Developed by Kaeser, the Sigma profile achieves power savings of up to 15% compared with conventional screw airend rotor profiles for a highly energy-efficient solution. In addition, all Kaeser rotary screw airends are powered by premium-efficiency IE3 drive motors for maximum performance and reliability.

Combining a rotary screw compressor with a compact integrated refrigeration dryer makes the CSD(X) T units ideal where the user requires an all-in-one solution. The integrated refrigeration dryers in these units also provide further energy savings, with a sophisticated control on these dryers ensuring that they are only active when compressed air actually needs to be dried. This achieves the required compressed air quality with maximum efficiency.

Moreover, where compressed air demand fluctuates the CSD(X) T SFC series really comes into its own. Utilising a variable-speed drive, these units have been designed to vary the speed of the airend to directly match the FAD (flow) required by the end user. This saves energy, maximises service life and enhances reliability.

Since their installation, WTC has continued to rely upon Kaeser partner Air Maintenance, based in Seaford, Victoria, for ongoing maintenance.

Veitch concludes: “The main compressor system is now effortlessly powering the new air skates, which together can lift and manoeuvre some 300 tons of weight. All of the Kaeser compressors have proven to be efficient and reliable in operation, and we are particularly impressed with their ease of maintenance. It is also evident to us that upgrading the compressed air equipment is saving us energy.”