Pfannenberg’s enclosure cooling units installed in the Gotthard Tunnel

Under construction for 15 years, the 35 mile long Gotthard tunnel located in Switzerland opened in 2016.

The Gotthard Base Tunnel impresses with many outstanding features:

  • It is the longest railway tunnel in the world at 57 km and its tunnel run, with all the transverse and connection tunnels, stretches over 154 km.
  • From 2016, passenger trains should have a top speed of 250 km/h, reducing the travelling time e.g. between Milan and Zurich to under 3 hours and should almost double the haulage capacity on the Swiss North-South Axis to 40 m tons of goods.

Operating a tunnel poses a huge challenge for engineers and operators. All products and solutions have to meet the highest requirements and have to work perfectly even under harsh ambient conditions. In particular, this applies to electrical enclosures and their thermal management, which are subject to extreme alternating pressure loads, temperature differences and are also exposed to dust and moisture.

In close collaboration, Swibox and Pfannenberg have developed a special climate control concept for tunnel applications. Robust Swibox electrical enclosures with a pressure body which was developed especially to protect the cooling circuit and the side mounted cooling units with integrated controller and heater from Pfannenberg guarantee a high system uptime which are situated, in the 176 cross passages amongst other places.

These electrical enclosure cooling units ensure that the thermal pressure of the electronic components integrated inside the electrical enclosures does not become too high and that they work safely and reliably throughout their whole service lives.

 

Electrical enclosures withstand every alternating pressure

The largest technical challenges were the high requirements to the system of protection of the electrical enclosure, IP65, and also the high alternating pressure load which is caused by the trains passing through. When entering the tunnel, the train pushes the air ahead of it, causing overpressure until the train passes by the cross passage where the electrical enclosures are standing. As soon as the train has passed, the overpressure transforms suddenly to a corresponding under-pressure.

All the electrical enclosures and the installed cooling units are exposed to the load of this alternating pressure of up to +/- 5 kPa. It had to be ensured that all devices can withstand this alternating pressure mechanically, simultaneously implementing the high system of protection.

It was possible to meet these requirements, thanks to the mechanical unit custom construction developed especially in cooperation with the company Swibox. This construction ensures a leak-proof separation of the surrounding (outer wall of the unit) and the inside of the electrical enclosure (unit inside), also under pressure load. A special feature here is the developed pressure body inside which the components of the inner cooling circuit are housed. Therefore, it was not enough to use reinforced sheet metal: the selection of a suitable material and the increased material thickness in combination with specially installed stiffening plates led to the desired compressive strength.

Climate control concept of electrical enclosures does not only mean cooling

Another challenge in tunnels is the ambient air. Large temperature differences ranging from -20 °C to +40 °C, maximum humidity of 100%, and ferrous abrasion of brakes, rails and contact lines in the ambient air increase the risk of corrosion and show how different a tunnel application is compared to standard applications.

Therefore, a special enclosure climate control concept had to be established for specifically this application. In addition to the cooling units, which are predominantly used inside the mountains (ambient temperatures up to +40 °C), Pfannenberg heaters also had to be installed in the portal sector (ambient temperatures to -20 °C). These heaters ensure that the temperature inside electrical enclosures does not fall below the so-called dew-point (the temperature that moist air has to drop to – by unchanged pressure – so that the amount of water dissolved in the air is precipitated as condensate). At the dew-point, the relative humidity is 100%; that means that the air is saturated with water vapour.

Pfannenberg’s new generation of controllers, designed especially for this project, were also installed. This is especially important to prevent unplanned failures and downtime and, by planning maintenance works in advance, to guarantee a high level of system uptime. The controllers are not only used directly inside the cooling units. The climate controller was also integrated into 500 other electrical enclosures without a cooling unit. This makes a temperature monitoring system possible, which, like the climate control units, can communicate with the tunnel control system and, if necessary, can be replaced with such, without having to reinstall the data transfer.

In 2010 the first cooling units were delivered to the company Swibox. In the meantime, all units have been delivered and will be installed one by one, together with the electrical enclosures, in the 176 cross passages of the Gotthard Base Tunnel. They have already been able to prove their reliability every day during the various test phases until the start of the scheduled railway operation on 2016.

Click here to read the full Case study!

Pfannenberg PATROL Flashing Sounder Used for Boat Warning Alarms


Safety is essential. Warning alarms save lives and prevent injury, this is why Pfannenberg Signaling Solutions are used throughout many different industries for numerous applications.

 

The marine industry is no exception as visual and audible signaling devices are required for boat warnings. The State of Alaska Department of Fish and Game contacted Pfannenberg to install a flashing sounder to replace the warning alarm on one of their boats.

Different options were discussed like a GL-rated version with the ability to use one or different tones to signify different events: bilge pump failure, fire, engine failure, etc. The customer finally decided to use our PATROL PA X 20-15 with a single tone. The advantages of this product are great:

  • 120 dB sounder
  • Up to 80 tones, 4 tone stages
  • High strength plastic housing adapted to marine environment (protection from splashing water)
  • Choice of 10 or 15 Joules strobe light
  • Choice of colors
  • New 10-year warranty!

Once installed the customer commented “Everything is working great with both strobe lights and audible alarm. Great product!”

The high quality of Pfannenberg’s Signaling products is internationnaly recognized and has once again been rewarded by winning the prestigious Red Dot Award.

Click here to discover our range of Patrol Series Signaling Technologies!

Topics: North AmericaIndustrial Safety & Signaling Solutions

Pfannenberg’s North American Headquarters expansion project


We are growing! We are currently about 1/2 way through the expansion of our North American headquarters. Once completed we will be adding new engineering and office space to accomodate our growing team.

Our new expansion project measures 5.735 ftand will feature new engineering office space, a laboratory and a 1.800 ftsecond floor dedicated to meeting rooms.The production space will be redesigned to improve the workflow between manufacturing and shipping/receiving with new ramps and fork truck paths for better material handling.

The laboratory will also host a new environmental test chamber which will allow the engineering team to increase our product sizes and test them under extended temperature ranges from – 40°C to + 70°C with a cooling capacity of 40 Kw. This new chamber will also support UL certification.

Here at our North American headquarters our three-year sales growth is nearly 28%. With this growth we have been recognized as one of the fastest growing companies in our region. This building expansion will enable the Sales/Marketing, Engineering and Production teams to work together in a more efficient way to meet the demanding market expectations.

Work is expected to be completed in October.

Topics: North AmericaCompany News & Annoucements

How to select the right chiller for your application


Whatever your industry, choosing the best packaged chillers to meet the demanding requirements of today’s industrial applications can be complicated. 

For that reason, Pfannenberg designed a 6 step guide to help you select the best chiller depending on your environment, process and type of application.

Click on the picture to open the PDF or use this link!

Pfannenberg designs versatile packaged chillers which are ideal for applications that have cooling requirements of less that a half a ton up to 30 tons. All chillers are shipped as factory packaged systems requiring only field power and piping to provide recirculated chilled coolant to virtually any process. Pfannenberg’s new CC Chillers are ideal for quick setup and trouble free operation.

Click here for more information about our range of Packaged Chillers!

Topics: Enclosure CoolingCooling UnitsPackaged Chillers