Metalastik hourglass springs chosen for Romania's new tram fleet

Metalastik hourglass springs from Trelleborg Industrial AVS have been chosen for Romania's new Imperio trams being built under a partnership agreement between Siemens, RATB (the Bucharest Surface Transport Operator) and local company Astra Vagoane Arad.

The Metalastik hourglass springs were chosen in preference to coil springs because they provide high levels of noise reduction and do not suffer from catastrophic failure. The hourglass springs are the key element in the secondary suspension, with four springs fitted on each bogie, eight per carriage.

Ralf Kubetschek, Key Account Manager at Trelleborg Industrial AVS, comments: "We are extremely proud that our Metalastik hourglass springs have been chosen for this significant project. Ours is a sophisticated, high-performance product which has proved its technical and whole-life cost advantages in prestige applications around the world. The consortium of Siemens, RATB and Astra Vagoane Arad have seen the value that it can bring to operators of the Imperio."

Metalastik hourglass springs are double hemispheres of rubber bonded to steel plates, giving excellent vertical load capacity and all-round flexibility. The design accommodates high horizontal, torsional and conical displacements, with a vertical characteristic which provides constant periodicity regardless of load. In addition to high-quality ride performance, the design offers simplicity, long service life and low maintenance. This type of spring was originally developed over 30 years ago, and has been applied on various rail platforms worldwide, with an associated excellent service record.

Prototype unveiled

Under the partnership agreement, Siemens will supply the electrical equipment, while Astra Vagoane Arad will build the rolling stock. The aim is to produce a tram costing some 30 per cent less than other international manufacturers. The prototype was unveiled outside Arad city hall on 25 August 2011. The company is planning to offer metre and standard gauge versions of the Imperio, with a choice of three or four low-floor carriages, giving capacity from 168 to 240 passengers.

The whole fleet of Romanian rolling stock is regarded as obsolete, which means that there is a need for at least 1500 new trams, without taking into account demand from other countries such as Hungary. Bucharest has the fourth-largest tram network in Europe, with over 350km of track. There are also comprehensive networks in other major cities, such as Timisoara, Cluj, Constanta, Brasov, Craiova, Iasi, Galati and Braila.

To find out more about Metalastik hourglass springs, visit the website at www.trelleborg.com/industrialavs.