As the lights were illuminated on the 2016 Christmas tree at Windsor Castle, they sparkled with some very special baubles that were hand blown and adorned with various emblems, the stamps for which came from Kaeser compressors.

Coburg, the home of Kaeser compressors and the English royal family share a long and storied history together. Prince Albert, Queen Victoria’s husband, came from the House of Saxe-Coburg and Gotha and grew up in the picturesque Franconian city. In 1848 he brought the first Christmas tree to the English royal household and introduced the tradition he knew so well from his hometown and which would later be adopted throughout the kingdom.

It was this year that Prince Hubertus, the current hereditary Prince of Saxe-Coburg and Gotha, had the idea of presenting Queen Elizabeth II with a Christmas tree as a 90th birthday gift. Coburg and the bordering region of south Thuringia are renowned for their Christmas products. The celebrated fir trees grow in the Franconian Forest and south Thuringia has produced unique hand blown glass Christmas tree decorations for centuries.

It is no surprise, therefore, that there’s also something special about the baubles on the royal Christmas tree. All of the approximately 2000 baubles are hand blown and are partially adorned with one of various emblems which required specialised stamps in order for them to be embossed into the baubles. These were produced in the Kaeser training centre.  As the Training Manager, Rüdiger Hopf, reminisces; “When the request came in, it presented a jolly and interesting challenge.” The reason was that while baubles are round, drawings or graphics are typically flat. In addition, despite the round shape, the embossing had to have the same depth at all points. Furthermore, no templates or specifications relating to the motifs were available that could have been used in a CNC machine. All emblems therefore had to be drawn by hand. The complexity of making the request a reality was no easy task, particularly since time was of the essence.

However, Nina Bortenlänger, a trainee in technical product design, quickly mastered the graphics challenge, Matthias Gähde, a trainee cutting machine operator, then produced the stamp blanks and the colleagues in the jig department then patiently milled the stamp profiles with micron precision. Because the work had to be so precise, five hours were needed to machine each emblem. The project required about a week of work and, it has to be said, put a smile on everybody’s face. As Nina Bortenlänger explains; “It was really cool to know who you’re doing it for.” The effort also didn’t go unnoticed elsewhere. The glass blowers in Lauscha were impressed by the exceptionally high quality of the stamps as they produced the baubles embossed with the emblems. It is also worth noting that one of the embossed baubles will be presented personally to the royal family as a gift and, after Christmas, will presumably find a home in a museum.

The tree officially started on its journey from Coburg to Windsor Castle on the 12th of November. The official lighting ceremony for the 13-metre tall fir tree then took place in the square in front of Windsor Castle on the 19th of November. The Queen requested that it take its place there, as the Royal Family was to spend the Christmas holidays in Windsor and would be able to cast an admiring gaze upon the majestic fir tree and its glinting baubles from Coburg. The tree also proved to be a big hit with the many visitors to Windsor, as well as with the town’s inhabitants, and continued to bring joy to all there as a festive gift from Coburg until the 6th of January.

The holidays are over; it’s now 2017 and Kaeser is once again pushing the boundaries of compressed air efficiency and availability with its latest generation DSD.3 series rotary screw compressors. At the heart of every DSD.3 series compressor is a high performance Kaeser rotary screw compressor block equipped with the flow-optimised and energy saving ‘Sigma Profile’ rotors. In these next generation models, the Sigma profile rotors have been further refined. Together with additional optimisation measures, the new DSD.3 series machines therefore boast up to six percent better power performance compared with previous models.

They also include a ‘super premium efficiency’ IE4 electric motor that complies with and exceed prevailing Australian GEMS regulations for 3 phase electric motors, whilst also contributing to lower energy costs. In addition, transmission losses associated with gear or belt drive solutions are further eliminated with these 1:1 direct drive systems. All models feature a built-in Sigma Control 2 industrial PC-based compressor controller that is responsible for dynamically adjusting the flow rate to match actual compressed air demand thereby assuring further energy savings.

Relevant information can be viewed at a glance from the easy to read display. Unique RFID technology further assures secure login, meaning that service work and system changes to the compressor can only be performed by authorised personnel. Energy saving control modes, variable communication interfaces for communication with centralised control systems, and an SD card for update and backup are just some of the many features available on the Sigma Control 2.

A sensor-controlled electronic thermal management (ETM) system can be found in the latest generation DSD series rotary screw compressors. The ETM dynamically controls the screw compressor block discharge temperature. The control valve actuator is controlled via signals from the Sigma Control 2 controller, which is coordinated with the oil cooler’s speed controlled fan. For the end user, avoiding unnecessarily high screw compressor block discharge temperatures leads to reduced energy consumption and potentially a longer fluid service life.

The DSD series rotary screw compressors are also available with heat recovery. All models can be optionally equipped with an integrated fluid/water plate-type exchanger and an additional fluid-thermal valve. The Sigma Control 2 controls the compressor temperature to ensure that hot process water supplied by the heat recovery system attains the desired water outlet temperature. In addition, if all of the heat energy is drawn off by the heat recovery system, the Sigma Control 2 detects that cooling is no longer required at the package cooler and the fan on the oil cooler is shut down. This saves fan power at the oil cooler and reduces energy costs.

If heat recovery is not required it can simply be deactivated via the Control. The package reverts to operation with the lowest possible screw compressor block discharge temperature, creating further energy savings. Where absolutely dry compressed air is required, the DSD.3 series are available with integrated refrigeration dryer (DSD T) that requires 25 percent less power than the previous models. The refrigerant quantity has also been reduced to only 2 kg. This compact powerhouse now has a smaller footprint which has been reduced by around 17 percent on the previous generation.

The Kaeser DSD.3 series rotary screw compressors are available air- or water- cooled, with drive power 75 to 132 kW, working pressure 5.5 to 15 bar and free air deliveries from 3.6 to 25.45 m3/min. They are available as a standard machine, with integrated refrigeration dryer and/or with Sigma Frequency Control. For more information visit