Mercedes-Benz hand over 40,000th Citaro – and 20,000th Sprinter
Already the most successful bus of the modern era, the Mercedes-Benz Citaro notched up another record recently with the delivery of the 40,000th example in a ceremony at the company’s Mannheim headquarters.
It also becomes the most successful Mercedes-Benz PSV product of all time, overtaking the previous record of 38,000 achieved by the O.303 coach family before its discontinuation in the early 1990s
The 40,000th unit is an 18.13m long articulated Citaro GU intercity model which has been purchased by the Luxembourg operator Voyages Emile Weber. Externally, it is distinguished by a pearlescent metallic paint finish while the interior is trimmed in red. This fifth generation family business has a mixed fleet of 380 vehicles involved in all types of bus and coach operation including 50 bus routes.
As was explained at the event, the milestones have been steadily rolling in for the Citaro, since the 1,000th was supplied to Sudwestdeutsche Verkehrs-Aktiengesellschaft (SWEG) of Baden in Germany in February 2000. The 5,000th went to the Austrian Postbus organisation at the end of 2002 and within two years, in the autumn of 2004, the 10,000th went to Alsa in Madrid, now part of National Express, within another two years the 15,000th to Bergkvarabuss of Sweden.
With production running at over 3,000 a year, the 20,000th was supplied to Pflieger of Boblingen near Stuttgart in March 2008, the 30,000th to Linz of Austria in 2010 and now the 40,000th is about to enter service.
Citaro sales have been made to over 40 countries including all of the Western European nations as well as Japan, Dubai, Singapore, Australia, Mexico, Abu Dhabi and Istanbul.
The latest versions are quite considerably different to the original Citaro which was unveiled at the UITP Congress in 1997, which just happened to be held in Stuttgart. Full production commenced the following year. It is true to say that it wasn’t an immediate success because early examples encountered a number of issues. I remember driving one of the first and the matching of the engine and gearbox left a little to be desired.
A second generation model followed in 2006, distinguishable by a revised lower front panel and in 2011 the latest Citaro was unveiled, with accentuated wheelarches and a rounder profile, though still unmistakeably a Citaro. Production of the new Citaro and the previous version have continued to run alongside each other with left hand drive markets offered the option of both Euro5 and Euro6 engines in the new Citaro, though the UK market has had to wait for Euro6 for the latest version. To date, most UK Citaros have had the OM906 six cylinder unit though some articulated vehicles have had the more powerful OM457hLA.
Daimler Buses was the first manufacturer to offer the whole of its bus range with Euro6 engine options, the main unit in the Citaro being the vertical 7.7-litre OM936 common rail diesel with a power output of 299hp (220kW) and torque of 1,200Nm at 1,200-1,600rpm or, optionally, 354hp (260kW) and 1,400Nm. In some applications a horizontal OM936h version is offered. The 40,000th bus was equipped with a vertically mounted, 10.7-litre, six-cylinder, in-line, OM470 unit developing 360hp (265kW) and peak torque of 1,700Nm, which is an option. This was coupled to a six-speed ZF EcoLife fully automatic transmission.
For the UK, though the company has waited for the switch from Euro5 to Euro6 to introduce the new model, it is still the first of the major manufacturers to go over completely to Euro6 engines, with most competitors still offering Euro5 outside London. The last Euro5 Citaro has already been delivered to Bennetts of Gloucester. With the new engines, the key models available are the 10.6m long Citaro K and the 12.1m Citaro with either one or two doors.
At the same event, a further ceremony marked the handover of the 20,000th Mercedes-Benz Sprinter minibus to be produced in-house at the Dortmund facility to the Norwegian car park operator, Sandfaerhus Parkering, which operates two facilities at the Trondheim and Stavanger airports. One of two being delivered to the company, it is a City 65 powered by the Euro6 Mercedes-Benz OM651 2.15-litre, four-cylinder, 163bhp (120kW) engine developing peak torque of 360Nm. To cope with Norwegian winters it has double glazing, convection heaters, a heat exchanger in the low floor area, an electric warm air heater and an auxiliary heater for when stationary.
Dortmund produces an extensive range of options starting with the Transfer range of traditional minibuses and running up to the tri-axle Sprinter City 77 model with low floor and dual powered doors. Most of the versions offered in Europe are also offered in the UK and all models available at Euro5 are also offered at Euro6.
The UK range includes: the 17-seat Transfer 45; the high specification Travel with up to 17 Tourismo luxury seats; the lift-equipped Mobility 35 long wheelbase and Mobility 45 extra long wheelbase models with up to 17 Phoenix seats; and the City 45 low floor city bus with Citaro type seats for up to 13 including tip-ups and a maximum total capacity of 22 passengers. The Traveliner conversion is also offered on the five tonne Sprinter with 2.2-litre engine.
With production about to be increased by a further 300 units to just short of 4,000 annually, it could well be that one day the Sprinter production figure will overtake that of the Citaro. I’ll not go further into the Dortmund built range here because B&CB plans to revisit the plant and report fully on it in the coming months.
Production of the Citaro takes place at the Mannheim plant where Benz started building in 1908 and where trucks were built until 1960. The façade of the building remains in place carrying the Benz name. The Mannheim complex is a huge one which, in addition to the bus manufacturing operations also houses the medium and heavy duty engine manufacturing operations producing Daimler’s latest ‘world’ engines. It has 130 test cells undertaking both hot and cold testing and the fourth biggest foundry in Germany.
Across the whole site 9,500 people are employed of which over 3,300 are on bus production. Between 250-300 trucks deliver to the site daily, depending on the build programme.
With the exception of the Tourismo models built in Turkey, most of Daimler’s heavy duty bus and coach products for Western Europe have their frames built at Mannheim though only the Citaro is completed at the site which is the Bodyshop Competence Centre. The frames for the coach range are finished at the Neu Ulm plant built by Setra in 1991. After they have been cataphoretically dipped to protect against corrosion, all buses and coaches are taken by rail to Neu Ulm for painting as this is the Daimler Buses Centre of Competence for painting, the Citaros subsequently returning. Not all Citaros are completed at Mannheim; currently four and sometimes as many as six a day go by truck to the French plant at Ligny en Barrois to be finished. In the past some were finished in Neu Ulm.
Construction of the frames for the Citaro and of the coach ranges both take place at Mannheim but in separate parts of the facility. I was shown round the bus plant which begins by assembling the separate main body sections on very precise jigs. Some major structural sub assembly sections are built at the Czech plant at Holysov and brought in by truck for integration. Once complete, the sides, roof, underframe, front and rear sections are brought together in one of two bus marriage jigs and welded together in a process that takes one hour.
Dr Ewald Kling, Director Daimler Buses Produktionscenter Mannheim, told me that they worked to very small tolerances, which was very important, ‘because each subsequent operation is based on this being accurate. Get it wrong here and the bus will be wrong all the way through.’
A side benefit is that if you want to convert a vehicle from dual door to single door later in its life, you can order the necessary sections from the factory and they will fit exactly.
In the past, a car style moving assembly line was used to build the O.303 and while this is no longer the case, there were some interesting uses of technology including robot welding machines. There are only a limited number of these in use (six) because they can only be employed where there is not much variation in the item being produced, as each variation requires a different programme. Most welding is carried out manually and all welders have to be recertified annually. Marcus Watts told me that the welders employed at EvoBus UK in Coventry have to be recertified in Mannheim annually.
All of the steel sections used are cut by laser which gives an accuracy of 0.1mm, rather than the 2.0mm tolerance of a mechanical saw. Laser cut sections are not only more accurate, they require less energy to weld. Watching one of the many laser cutters it was interesting to note that in the first stage of the cutting process the part number is etched on to the part. Additional laser cutting machines were being installed as we toured the plant.
In contrast there were also machines, still capable of doing the job required, that looked like museum pieces, among them some massive Schuler presses dating from 1966.
Always one of the most interesting parts of a major steel bus manufacturing plant is the cataphoresis plant were the body structures have an electrostatic charge applied to them and are then dipped in a protective paint coating that ensures they remain protected throughout their working lives. The process starts with cleaning, then the surface is prepared with a phosphorous layer, the frame is washed down with demineralised water and electrodes are attached in order that the paint will be attracted to the metal. The complete frame is then completely immersed for 15-18 minutes in a 410,000-litre bath of water based coating which coats the frame, inside and out, with a 25,000 micron thick layer. Tilting the bus and small holes in the tubes, ensure the whole frame is coated. Apparently the liquid in this bath, which is 83% water, 16% pigment and 1% smoothing agent, costs €1m to replace every Christmas close down. After dipping it is rinsed, the electrodes are removed and the structure is dried and cooled.
Once the frames are protected they go to Neu Ulm for painting and on their return go back on to the lines where production moves on a stage every 28 minutes with two minutes allowed to relocate the vehicles.
Each of the two lines can cope with any variety of models from the extensive Citaro catalogue, whether solo or articulated, and front and rear sections of artics move along the lines independently, even on different lines.
Once they are complete, all buses are driven round the plant to check their key systems and after any necessary adjustments are taken on a 100km test run before they are rechecked and certified ready for delivery.
It was interesting to see other right hand drive vehicles going through the plant in large numbers. These were part of a series of orders for Singapore which will amount to 850 units by the time they are all complete. The final 80 vehicles are currently being produced and will be delivered by the end of July. Right hand drive Citaro K and Citaro demonstrators were to be seen along with the first two Euro6 Citaros for a UK customer; dual door buses with internal racking for airport use.
Production at Mannheim is currently running at 30-32 frames a day across bus and coach but has been as high as 34-36 during September-December to match the German buying pattern. Of the current total, between 19-20 are Citaros. Total annual production is between 3,500-4,000 complete buses plus around 5,500 coach bodies.
In the UK the first Citaros were sold to First Group in 2000 when 60 were delivered for use in Manchester. It replaced the O.405 and articulated O.405G which had enjoyed limited success, the most significant order being a batch of 100 delivered to Travel West Midlands that were completed in the UK.
Since then, Citaro have operated with all of the big groups, though in the case of Stagecoach only in London, while First, Go-Ahead and Arriva have all bought multiple batches. Trentbarton has bought examples and is doing so again, while municipal (and former municipal) fleet buyers have included Plymouth, Preston and more recently the Isle of Man. An interesting purchase was the Cardiff Bus acquisition of 20 units towards the end of 2013, the first Citaros it has bought but some of the last Euro5 models supplied. They have also proved popular with independent operators including: McGills, Universitybus/Uno, Western Greyhound, Epsom/Quality Line, deCourcey, Premiere, Stewarts and Bennetts. Specialist applications such as airports and car parks have seen other major orders won, notably from British Airways, NCP and APCOA, among others.
In total, over 1,250 Citaros had been delivered to the UK by the end of 2013 of which over 470 were articulated, though future articulated sales are likely to be limited thanks to the voodoo politics of the capital.
Talking to Till Oberwörder at the event, he explained that, contrary to the UK experience, demand for articulated versions was increasing elsewhere in Europe. Figures he subsequently supplied me with show that in 2010 articulated Citaro sales amounted to 750 units which was approximately 25% of the total sales volume. By 2013, sales had risen to nearly 900 articulated units, of total sales of around 3,000 units, moving the split to 30% of Citaro production.
Till also promised that CNG powered Citaros were on the way, but he could not say when. He commented, ‘Euro6 is and has been our number one priority.’
Mannheim always has been an impressive plant and by any standards the successive generations of Citaro have been a major success story. By the end of March there were already over 1,000 Euro6 Citaro buses in operation, which I understand was more than all other European bus manufacturers put together. Having already switched entirely to Euro6 for its engines for the UK Mercedes-Benz is ahead of the game in the UK and, with improved fuel economy over Euro5 a reality, the incentive for operators to take the plunge is a genuine one.