1. About us
  2. Success stories
  3. Case study Ceneri Tunnel Switzerland

Sealing cabinets and enclosures in the Alptransit project

Protection of technical equipment for safe operation of tunnel facilities.

Sealing cabinets and enclosures in the Alptransit project

The pressure-tight control cabinets in the cross passages and technical niches of the Alptransit Ceneri railway tunnel protect the electrical control equipment and crucial safety and radio technologies from dirt, moisture and heat. The cabinets are sealed with Roxtec cable transits.

"With Roxtec cable seals, we have an established and proven product that meets the client's requirements for pressure-tight yet flexible cable glands into which cables with pre-assembled connectors can be inserted,” says Christian Bracher, CEO of cabinet systems provider Swibox AG.

Highest safety level

The safety standards for the construction and operation of railway tunnels are particularly strict. In the new transalpine rail link, with base tunnels at Gotthard and Ceneri in Switzerland, the demands are significantly high. Since passenger and freight trains pass through the Ceneri tunnel at 250 km/h, all components used must withstand enormous pressure and suction loads. In addition, there are considerable temperature differences, high humidity and extreme dust loads.

The combination of Roxtec cable seals and Swibox special solutions, such as air-conditioning systems, high-density switch cabinets and branch housings, ensures reliable functional integrity and protection of all electrical components. Both Roxtec products and Swibox solutions have fully met the demanding tests in advance and contribute to the safe operation of the tunnel. The innovative systems meet the requirements for tunnel and building construction. 

Covering multiple challenges

In the rescue tunnels, Swibox G10 cabinets, partly air-conditioned, and G10 wall cabinets are used. The Roxtec CF 16 stainless steel frames with Roxtec compact sealing modules (CM) are installed in these pressure-resistant and air-conditioned crossover enclosures. Also, a range of Roxtec regular sealing modules (RM) ensures that the tailor-made cabinet transit frames used by Swibox fulfill the requirements.  

Roxtec's high-performance seals make a significant contribution to ensuring the required air-tightness.

They master the challenge of the crossover climate of the environment, such as power loss, pressure load, dirt, air humidity and geothermal heat, as well as the influence of the waste heat from the cabinets.

Roxtec cable seals meet the client's requirements
Christian Bracher, CEO, Swibox AG

Why Roxtec?

  • Airtight and pressure resistant
  • Fire-, water- and dust-tight
  • Easy installation, inspection and maintenance
  • Uniform space-saving high quality design
  • Spare capacity for retrofits and upgrades

Project facts

Project description

Construction of the Ceneri tunnel of the environmentally friendly flat railway through the Alps

Involved companies

AlpTransit Gotthard AG – responsible for the tunnel project, Swibox AG – responsible for the development and implementation of control cabinets and housings


Sealing of cable entries in control cabinets and housings in the tunnel system

Sealing requirements

Tightness at +/-10kP alternating pressure loads, Vibration and shock-wave protection, IP65 for protection against dust and moisture, Heat protection, Service life of minimum 25 years

Roxtec products

A variety of Roxtec cable sealing solutions, including the compact Roxtec CF 16 AISI304 cable transits and Roxtec sealing modules for tailor-made transit frames for cabinets