Harry Hondius reports from Haren

SIX of the 15 six-car M6 series trainsets being built for the Brussels metro by CAF have now entered service, after the first unit began carrying passengers in September. The first unit was delivered in April (RG 5.07 p253), having successfully completed more than 5 000 km of trial running at Alstom's Valenciennes test track, where the remaining sets will each undergo 1 000 km of test running.

The Brussels metro needs additional rolling stock as it is becoming a victim of its own success. Annual passenger traffic has risen sharply, from 78 million passengers, in 2000 to no less than 112·5 million in 2006.

The current fleet comprises 53 two-car and 37 three car units, which were built by Bombardier and Alstom between 1976 and 1999. The new M6 sets were ordered as complete six-car units to make full use of the 100 m long platforms at each station. The fully-gangwayed 'Boa' units mark a radical departure from STIB's older stock.

CAF was selected as prime contractor in December 2003 (RG 2.04 p65), and subsequently awarded the electrical equip-ment subcontract to Elin EBG of Austria.

The M6 trainsets will operate on the principal east-west corridor linking Erasme and Roi Baudouin in the west with Hermann Debroux and Stockel in the east. Completion of the 'Ring Line' linking Delacroix to Gare de l'Ouest by the end of 2008 will allow the 43 km network to be restructured as four separate routes:

  • U1 Stockel – Central – Gare de l'Ouest (12·7 km);
  • U2 Simonis (high level) – Ring – Simonis (low level) (10·3 km);
  • U5 Erasme – Central – Hermann Debroux (17·6 km);
  • U6 Simonis (low level) – Ring – Simonis (high level) – Roi Baudouin (15·5 km).

STIB plans to concentrate the M6 cars on Line U1 services. The existing cars, which are 18·2 m long and 2 700 mm wide, will work in five-car formations on lines U2 and U6, and in a mix of four and five-car sets on Line U5. These older vehicles have welded aluminium bodies and monomotor bogies, with two 264 kW motors per car.

STIB has an option for a further five M6 trainsets, which it hopes to exercise by the end of 2007. Further units could follow as the authority looks to replace its older cars from 2015 onwards. STIB is also looking at full automation in the future.

A six-car M6 trainset is rated to carry 198 seated and 530 standing passengers at 4/m², compared to 40 seated and 137 standing per car with the older stock. The 1 350 mm wide inter-car gangways supplied by Hübner offer passengers unobstructed access from one end to the other, being covered by double-corrugated bellows. The two end cars have transverse seating, while the other four have longitudinal seats. There are three pairs of IFE doors on each side of each car, with 1 450 mm wide entrances 1 950 mm high.

Glazed screens separate the driving cabs at each end, giving a clear view throughout the train. However, the STIB drivers called strikes on September 17 and October 13, alleging 'safety' concerns which would require them to be visually insulated from their passengers.

The car body is an integrally-welded aluminium design, with a crash-resistant steel structure bolted to the cab ends and covered by a glass-fibre nose. The single-glazed safety glass windows are glued into the frames, and video cameras are installed in every car. Merak has supplied heaters for the saloon areas and air-conditioning for the cabs; air-conditioning of the passenger saloon was not deemed necessary as the average temperature in the tunnels is 20°C.

As STIB's Delta workshop can only accept three car trains, the units are designed to be split for maintenance, with automatic couplers and control panels in the centre cars. Sliding doors close off the gangway. The Dellner automatic couplers are mechanically compatible with the Schwab (formerly GF+) type used on the older stock.

The trains take 750 V DC from a bottom-contact third rail supply, using Pintsch-Bamag collectors. Each M6 trainset has eight of the 12 axles driven by fully-suspended asynchronous motors – the centre car of each half-unit is unpowered. All of the traction equipment is mounted underfloor, with the two motors on each bogie fed by a duo-inverter. Two static inverters rated at 90 kVA provide 400 V three-phase AC and 110 V DC for the auxiliary equipment, backed up by a pair of 130 Ah Ni-Cd batteries.

The bogies are of the air sprung bolster type with a ball-bearing pivot and horizontal shock absorbers between the bolster and bogie frame. Clouth rubber/metal springs are used for the primary suspension and axle guidance. The TSA air-cooled motors drive the axles through a semi-suspended Flender gearbox.

The primary service braking is regenerative, but eight brake resistance units are provided in case of poor line receptivity. Below 15 km/h electro-pneumatic braking is blended in. All axles have SAB Wabco air-operated spring-applied disc brakes; each bogie also has two Faiveley magnetic track brakes. The full emergency braking rate is 3 m/s².

The cars ride well, the internal noise level with full ventilation is 55 dB(A) when stationary. This rises to 73 dB(A) in the cab when running at 60 km/h with a side window open, but only 65 dB(A) in the middle of the train at 50 km/h. The electronics seem completely silent.

Technical data for M6 metro cars

Train formation M-T-M+M-T-M

Train length m 94·0

Length of intermediate car m 15·5

Length of end car m 16·0

Width mm 2 700

Floor height above rail mm 1 050

Doorway width mm 1 278

Tare weight tonnes 160

Gauge mm 1 435

Bogie wheelbase mm 2 200

Bogie centres mm 9 500

Wheel diameter (new/used) mm 830/760

Traction voltage (nominal) 750 V DC

Traction motors 16 x 345 kW

Continuous rating kW 2 160

Power-to-weight ratio kW/tonne 13·5

Maximum speed km/h 72

Seated passengers 198

Standing passengers, at 4/m² 530

Average weight kg/m² 630

Weight per seat kg 808

Price €m 8·1

  • CAPTION: RIGHT: Longi-tudinal seat ing will encourage a smoother distribution of standing passengers along the train
  • CAPTION: below: Hostler control panels are provided on the two centre cars for shunting half-units in the depot