Skip to main content

Siemens Mobility drives with EMKA hybrid closure

Innovative design, market-relevant certifications and extraordinary know-how: Siemens Mobility and EMKA are two experts in their respective field, in this case train technology. The two companies have already successfully implemented many projects together. Whether in the Munich’s subway, the Bangkok metro or, in the not-so-distant future, in the London Tube: EMKA compression latches ensure a safe and accurately fitting closure technology on the converters manufactured by Siemens Mobility – including a topic that is particularly important in the railway sector: the right fire protection.

Tens of thousands of compression latches secure converters in trains worldwide

Siemens Mobility with its headquarters in Munich is a subsidiary of the Siemens Group. Responsible for the international mobility business, it has been organised as an independent Siemens Mobility GmbH since 1 August 2018. Its business areas include the planning and construction of complete turnkey rail systems, the production of signalling and control technology as well as vehicles for rail traffic and maintenance and services for the infrastructure. Of a total of 36,800 employees, around 4,400 work for the “Components” division. They manufacture converters, pantographs, control systems, gearboxes, railway motors, bogies, and braking systems for rail vehicles worldwide. For example, the classic ICE train, the Metro China and the hybrid tram Avenio in Doha benefit from the manufacturer’s innovative technology.

To ensure that passengers are transported in a comfortable and safe environment in the public trolleys and on national train journeys, Siemens Mobility equips rail vehicles worldwide with key components. Traction power converters and auxiliary converters are responsible for the power electronics and drive technology.

Traction power converters are used to generate the three-phase current for the drive motors from the respective traction current system of the overhead line or conductor rail.

They are used in all applications and installation variants such as subfloor, roof-mounted, and indoor applications. Auxiliary converters supply the entire power and voltage range in order to realise a compact and highly efficient on-board power supply for all train applications. Important criteria for these components are their flexibility as well as their low weight and size.

This is where EMKA comes into play: For many years Siemens Mobility has been cooperating with the expert for locking technology in numerous projects. The main objective always was to lock the converter housings and fire-­protection equipment safely. EMKA locking devices are thus used worldwide in vehicles for metro systems, for trams and light rail vehicles, for local and regional traffic, in passenger coaches and also for intercity and high-speed traffic.

Flexible design and easy installation

For its closures EMKA exclusively uses materials which are certified according to the currently valid fire protection standards for rail vehicles. The product range includes closures and sash fasteners for the exterior as well as the interior of rail vehicles. Therefore, their use is suitable for all placements of converters on and in the train. These are used in the Inspiro models, for example. The requirement: The user must be able to open and close the covers of the converters as quickly as possible. Depending on the design and number of vehicles, more or fewer inverters are required.

Therefore, depending on the project, it is a question of thousands to several tens of thousands of closures which EMKA supplies to the suppliers of ­Siemens ­Mobility. These suppliers install the compression latches in the covers of the converter housings and deliver them to a Siemens Mobility location where the technology is installed. Decisive is the construction of the EMKA compression latch and the possibility to combine different reeds. Thus, an adaptation to the geometry requirements of Siemens Mobility can be made. The internal reed can also be adjusted in depth.

32,000 compression latches for the London Tube

In a further project, a newer type of EMKA compression latch will be used in the future: A total of 32,000 hybrid compressiones will be used in the “New Tube for London” programme. Siemens Mobility is equipping the Piccadilly Line of the London Underground with 94 new trains of the Inspiro model, which are to be delivered from 2023 onward and put into service in 2024. Inspiro is a vehicle concept which has already been put into service in the Munich Subway as well as in the Warsaw, Kuala Lumpur, and Bangkok Metro – also equipped with EMKA compression latches.

After a series of tests with products of numerous manufacturers, EMKA was awarded the contract with its hybrid compression latch. What was decisive for this decision? The innovative combination of safe and cost-effective use. The hybrid combination latch differs from the conventional version, especially by its housing, which is made of aluminium. The stainless-steel lock with aluminium housing scores points above all for its high resistance to weathering.

Initial fears on the part of Siemens Mobility, that the material combination of aluminium and stainless steel might not pass the fire protection test, were quickly dispelled by EMKA. In addition to its shock and vibration resistance, the closure is certified for fire protection according to DIN EN 45545-3 E20. Compared to a purely stainless-steel product, the hybrid model offers a cost-effective alternative – even for areas with fire protection requirements.
It also impresses with its compact design and high weather resistance, which is particularly important in the railway sector for mounting the converters, either on the train‘s roof or under the floor. A further plus point: the weight saving of up to 30% resulting from the hybrid design is particularly advantageous for applications in the transport sector.

Markus Müller, Project Manager at Siemens Mobility GmbH, sums up: “I experience the cooperation with EMKA as very open and innovative, especially with regard to the development of the hybrid version. Here, EMKA was a reliable partner and showed high commitment, thus the challenges could be solved reliably”.