MAN BusDays: Innovation meets Perfection
On 15th and 16th March 2018, MAN Truck & Bus invites you to its in-house exhibition at the MAN Forums in Munich. On display will be the complete vehicle portfolio, including the new MAN Lion's City, as well as the wide range of services provided by the commercial vehicle manufacturer.
MAN Truck & Bus is expecting up to 1,500 visitors from all over the world, spanning customers, drivers and fans, at this year's in-house exhibition, MAN BusDays. On 15th and 16th March 2018, they will have the opportunity to not just to view the complete vehicle programming of the MAN and NEOPLAN brands but also to take them for test drives. A special highlight is of course the world première of the new MAN Lion's City. But even the NEOPLAN Cityliner shown can be sure of admiring glances: On the outside, a striking sticker adorns it as a continuation of the "Moving Art" project by the Berlin artist group Klebebande. And the luxuriously equipped interior by the MAN Bus Modification Centre welcomes visitors. Every passenger will feel like a VIP in the spacious rear lounge. The kitchen will take care of your needs with its hot-air blower, refrigerator, dishwasher and thermobox.
The daily programme is rounded off by lectures from experts. In addition to the products, the extensive services of the commercial vehicle manufacturer are also discussed, such as maintenance management, repair services, original parts and accessories, as well as financial services. For example, MAN's own training provider MAN ProfiDrive® promises to improve safety and efficiency through its practice-oriented driver training courses. In the area of passenger transport, the focus is on safety aspects and their improvement. When optimising the economic efficiency of driving, the goal is fuel savings of up to 10% through the intelligent combination of driving skills, forward-looking time management and economic route planning. MAN's own training provider MAN ProfiDrive® .
MAN is devoting its own exhibition area to the challenges of switching to alternative drive systems. The experts of the MAN Transport Solutions consulting team will answer all questions concerning the path from "low emissions" to "no emissions". The qualified consultants can cover not only the vehicle but also questions about the infrastructure and the energy requirements as well as maintenance concepts and the fleet design through their wealth of experience.
MAN Lion’s City: Setting standards in every respect
With the new generation of the MAN Lion’s City, a completely new type of urban bus is being introduced into the inner city. A plethora of technical innovations have been combined with the new MAN bus design.
As part of the BusDays in-house exhibition, the new MAN Lion's City is celebrating its world première. With a clear focus on profitability, driving comfort, technology and design, the developers have taken the task upon themselves of setting new standards for all components. Examples include the all-new driveline with the MAN EfficientHybrid, the independent wheel suspension on the front axle, the LED light functions and the new modular interior. This is because the new MAN Lion's City marks the beginning of a new era, 18 years after the unveiling of its predecessor. It therefore has been designed to meet all current and foreseeable future legal standards.
From the outside, the new city bus is an unmistakable example of the new MAN bus design. It has a range of eye-catching features, including its distinctive headlights, which incorporate an LED band that acts as daytime driving lights, and the typical black MAN front panel with chrome trim, as well as its large side windows. Not only do these lend the vehicle an impression of dynamism, but as aspects of segmented panelling, they also contribute to the improvement of Life Cycle Costs (LCC). In a nod to modern smartphone design, even the rear has become a distinctive feature, as we can see on the new MAN Lion’s City and the new MAN Lion’s Coach. What’s more, it also enables perfect accessibility to the various components.
The MAN EfficientHybrid is now even more economical thanks to its new D15 engine, stop-start system and reduced weight
However, the new materials and manufacturing processes used not only make the new city bus look good, but also lighter, more robust and also increases its ease of use, e.g. on service and engine compartment flaps. For example, the new 12-metre variant of the MAN Lion's City has slimmed down to around 1,130 kg compared to its predecessor, which with its D20 engine resulted in higher fuel consumption. This includes, among other things, a redesigned engine compartment flap, which does not require a steel frame, as well as a thinner rear window and a weight-optimised side wall lining made of natural-fibre-reinforced polypropylene.
A further contribution to its economic performance is the new, lighter D1556 LOH engine, which already complies with the Euro 6d emission standard valid from 1 September 2019. As an innovation, only the SCR technology (Selective Catalytic Reduction) is used in conjunction with the MAN CRT (Continuously Regenerating Trap) filter system; meaning that exhaust gas recirculation is no longer necessary. The highly efficient 9-litre engine is available in power levels 280, 330 and 360 hp, so it ideally covers the typical applications of city buses.
Optionally, the new D15 engine can be supplemented with the MAN EfficientHybrid module, a system that significantly reduces fuel consumption and emissions by up to 16%. In addition, the standard start-stop function of the MAN EfficientHybrid ensures whisper-quiet stop phases at stops and traffic lights. At the heart of the system is the crankshaft starter generator, an electric machine that converts mechanical energy into electrical energy during braking. The recuperated energy is stored in an UltraCap module on the vehicle roof, which is significantly lighter and more compact compared to a battery of similar capacity. The energy stored in the UltraCap ensures that the onboard power supply is independent of the drive, which not only relieves the diesel engine, but also enables the engine to be switched off during vehicle standstill. By reversing the operation of the crankshaft starter generator, the MAN D15 engine can be restarted within a few moments and supported by the boost function during subsequent acceleration.
Innovations also for independent wheel suspension, PCV silencers and doors
As the first city bus from MAN, the new Lion's City now has independent wheel suspension. As a result, the movements of the wheel and hub carrier are only slightly transferred to the opposite side when the wheel rolls off road bumps. Overall, a softer designed silencing is possible because the lower unsprung masses act on the force.
The new PCV dampers (Premium Comfort Valve) in the shock absorbers replace the previous silencer technology as a series solution. These purely hydraulic vibration dampers enable optimum chassis tuning in terms of driving comfort and vehicle stability in typical applications such as start-up and driving over long bumps or short obstacles. Thanks to a new oil management concept, significantly more parameters are available, so that a specific tuning for each axle variant is possible, which in turn leads to significantly more comfortable handling.
MAN has also made further improvements to the doors with the new city bus generation. They continue to come from MAN's own door portfolio, but they are 10 cm wider and impress thanks to their harmonious, faster and direct door movement. Pneumatic outward- and inward-swinging doors as well as electro-hydraulically driven inward-swinging doors and swing doors are available. Proven components are used, meaning that no lubrication nor adjustment operations are required during operation. All of this makes the doors reliable. By using the modular kit a cost-effective spare parts supply and high availability is guaranteed, which in turn benefits the LCC.
All light functions available in LED
An example of the claim to set standards with the new MAN Lion's City is provided by the headlamps on the front and rear. It is not just the daytime driving lights where MAN is making use of LED technology. The main headlights are available for the first time in full-LED and together with the LED tail lights form part of the standard equipment. The LED lamps in all lighting functions not only emphasise the characteristic design of the new MAN Lion's City as a special light signature, they also contribute to safety and reduce operating costs. In addition to its high energy efficiency, the lamp boasts a long service life of up to 10,000 operating hours and high reliability, eliminating the need for expensive lamp replacement. At the same time the visibility improves: LED dipped and high-beam headlights are around 50% brighter than halogens. Also, LED light is more diffuse, and, at the same time, has a much greater range.
The interior also uses modern lighting technology. Indirect and optionally continuous LED lighting in warm white as well as optionally coloured ambient light provide a uniform, modern, dynamic lighting design. The engineers paid particular attention to the reflection-free design in order to minimise glare at the driver's workplace.
New seat bracket for flexibility and easy cleaning
This underlines the bright, friendly and visually clean impression of the new interior colour and trim concept. A great deal of thought goes into selecting light and dark colours to provide appropriate functional support to functional areas. At the same time, the new seat bracket with optimised seating distances and the attachment of the seats to side rails not only creates more space but also makes cleaning easier. A standardised seat frame is attached here via two rails on the side wall. Any seat shell can be easily and flexibly mounted using adapters. Even if you stand, you do not have to do so without comfort and safety: The new ceiling support rods with an oval handle profile provide a more ergonomic grip.
Ergonomics, comfort and safety for the driver
In the new MAN Lion's City, the driver also finds a revised and optimised space, which perfectly fits into the design concept with the elegantly curved cabin door. With a focus on ergonomics, comfort and safety, the positioning of the switches and instruments has brought about an increase in user-friendliness. The controls are now arranged in three zones according to the frequency of use, an optional additional right-hand tool rack allows for additional DIN equipment or monitoring monitors. The cup holder and USB port are located in the side panel, and additional storage options are on offer, such as a lockable driver bag compartment and a magazine net.
The driver's seat can now be adjusted horizontally for more ergonomics via an optimal seating position. The instrument panel moves synchronously with the movement of the steering wheel. The standard built-in high-resolution 4-inch colour display also ensures maximum visibility. Further safety bonuses include the driver's increased sitting position and the front-opening driver's door. A modular pane on the driver's door, which can be extended to the windshield, can additionally provide security against attacks.
The new city bus generation will also be manufactured in the MAN plant in Starachowice/Poland starting in August 2018.
MAN D15: THE engine for all city buses
With the new D1556 LOH, MAN will in the future rely exclusively on SCR technology to achieve the Euro 6d emission standard. The new 9-litre engine impresses thanks to its low consumption and high load capacity.
For the power range of 300 to 400 hp, a 9-litre engine is the ideal capacity (9036.59 cc). The prior gap in the MAN engine programme has now been filled, thanks to the new D15. The vertical engine offers power from 280 to 360 hp (206 - 265 kW) and already fulfils the Euro 6d emission standard. The technical innovation is that now only the SCR technology (Selective Catalytic Reduction) is used, meaning that exhaust gas recirculation is no longer necessary. In conjunction with the self-regenerating filter system MAN CRT (Continuously Regenerating Trap), NOx emissions are almost completely eliminated.
The components which influence the mixture formation were specially adapted to this operating method for this purely engine-internal solution. As part of the new Common Rail injection system, the turbo charger can be designed to be optimised for efficiency. This includes, for example, the fact that the developers at MAN achieve optimum fuel fluidisation by, among other things, designing the nozzles and the combustion chamber geometry. Further innovations in the engine include new steel pistons and buckle valves, which allow an injection pressure of up to 2,500 bar or an ignition pressure of up to 230 bar. The curved valve disk shape reduces the sliding movement and thus the wear between valve and seat ring in the cylinder head to zero when opening and closing the valves. Buckle valves as well as steel pistons have proven their worth in the MAN D38 engines and impress thanks to their long service life and reliability.
The new common rail components also include a new pressure relief valve (PRV). This mechatronically actuated valve ensures the injection pressure in the common high-pressure distributor strip depending on the operating state. In normal operation, the PRV is de-energised and closed by mechanical spring force so that full pressure is available on all injectors in the manifold. When in dynamic mode, when switching or stopping the engine, the PRV opens with the help of an electromagnet. This drains fuel from the manifold into the fuel return line, reducing the pressure in the manifold to the desired level.
D1556 LOH: Light, quiet, clean
The positive consequence of the high injection pressure is the finest atomisation of the fuel and thus efficient combustion, which is reflected in the very favourable fuel consumption as well as the low exhaust emissions. In addition, the high compression also has a positive effect on the cold start behaviour. At the same time, the higher mean pressures allow the D15 to be used more thermodynamically. This contributes to better overall balance, as more energy is converted to propulsion and less to heat.
However, the exhaust gas aftertreatment with SCR technology requires a high exhaust gas temperature. In order to be able to maintain this constant, even in partial load operation, for example with a simple topography or low vehicle utilisation, the D15 has an additional charge air throttle valve in front of the engine. This accelerates the warm-up of the engine and thus ensures that the required exhaust gas temperature is reached faster. The controllable charge intercooler flap together with the exhaust gas flap after the engine supports the temperature management for optimal operation of the exhaust system.
The D1556 LOH replaces the previously installed D2066 LUH in the new city buses by MAN. Like the D20, the new engine is also characterised by very good dynamic handling due to the optimal turbo charger configuration, but with lower weight and better efficiency. The former contributes to a better axle load distribution by relieving the rear axle. This is an important issue especially with a large overhang and a lot of standing space, as this increases the payload. In addition, a lower weight also contributes to lower fuel consumption.
The weight savings were achieved, among other things, by a consistent optimisation of the individual components. Modern simulation methods were used during the development stage for this purpose. As a result, in spite of the reduced component weight, in many cases an optimal structure with respect to the load could be found, which also ensures an increased service life of these components. The production in aluminium instead of steel or iron, for example, for the carrier for the coolant compressor, and the direct mounting of mounting parts on the crankcase saves weight. As a result of all these measures, the performance weight of the D1556 LOH was improved to 2.5 kg/hp (3.4 kg/kW).
New manufacturing processes and materials contribute to weight reduction on the one hand and to improved acoustics on the other hand. For example, components with large radiating surfaces, such as the cylinder head cover, are designed in plastic structure-stiffened geometries. This effectively dampens the noise emissions from, for example, the valve control of the cylinder head. In addition, in straight high gears, for example, from the crank mechanism to the camshaft, smaller modules are used. As a result, more and more teeth are always engaged, which in addition to the weight advantage also brings slight acoustic benefits and above all they are almost wear and maintenance free.
Due to this "fasting cure", the D15 has lost nothing of its performance compared to the previous engines. On the contrary: The maximum torque can already be achieved at low speeds. Specifically, this means a maximum torque of 1200 Nm at 800-1600 rpm for the 280 PS engine, 1400 Nm at 900-1600 rpm for the 330 PS variant and 1600 Nm at 900-1550 rpm at the strongest engine with 360 hp.
In contrast to a comparable engine with exhaust gas recirculation, the new single-stage turbo charger uses the entire exhaust gas mass to increase efficiency. The result is optimal power delivery and a very good response of the engine, as well as favourable consumption at the same time. In the 280 to 360 horsepower ratings, the engine is equipped with a wastegate that, if necessary, directs some of the exhaust gases past the turbo charger so that it does not overcharge at higher engine speeds.
Just like the D2676 LOH, which works in MAN and NEOPLAN coaches, the D15 now also has a regulated coolant pump. Unlike the previously used rigid, uncontrolled and continuously-moving coolant pumps, the full-speed regulated water pump used at MAN enables demand-driven pumping of the coolant. The regulation of power is infinitely variable between 20 and 95 percent. Thus, with low cooling requirements, for example in light topography and with low load, 80% of the required mechanical power of the coolant pump can be reduced, which means there is significant potential for fuel-saving.
In addition, MAN has equipped the new D15 with needs-based control of the cooling components such as fans and coolant pump. As a special feature, in addition to the detection of the coolant temperature, there is also a sensing of the admission pressure in the cooling system. As a result, a drop in the cooling fluid pre-pressure can be detected early and counteracted if necessary, which prevents damage to the components. This increases operational safety and, on the other hand, fuel consumption drops due to energy-efficient engine operation.
An important contribution to the cooling of the engine is also made by the engine oil and the lubrication of such. When dissipating the heat, the oil must not overheat, as it would be subject to damage and would have to be changed earlier. On the other hand, if the temperature is too low, the friction is greater and the fuel consumption increases. In order to avoid temperature peaks, MAN relies on an optimised oil cooler (heat exchanger). On the other hand, the average oil temperature is increased in the cold and low load range via a thermostatically controlled oil cooler bypass in order to reduce the friction losses in the engine.
MAN EfficientHybrid: Especially clever
Optionally, the new D15 can be supplemented with the new MAN EfficientHybrid, a mild hybrid module that supports the diesel engine and can therefore make a significant contribution to saving fuel. In this case, energy recovered during braking is stored in an UltraCap module on the vehicle roof and then used to charge the vehicle battery as well as for the onboard power supply. The heart of this is the crankshaft starter generator, an electric machine that converts mechanical energy into electrical energy. Regenerative operation during braking recuperates energy that the electric machine uses during engine startup to start the engine. The MAN EfficientHybrid also includes a stop-start function of the engine.
To reduce the variety of variants, the new D15 engine is installed exclusively upright. Among other things, a new space-optimised cylinder head contributes to its overall low overall height. The optimised exhaust ducts also reduce the charge cycle losses for efficient combustion with favourable emissions and fuel consumption behaviour. The adapted directed gas movement in the combustion chamber additionally ensures low soot particle emissions. Flat valve seat rings shift the cooling closer to the hot areas. This compensates for the higher thermal load.
The vertical installation ensures good accessibility to service points such as oil and fuel filters. In addition, the simple and modular engine also contributes to a reduction in maintenance and service costs.