BMW M5 In Depth - Part 2
The Executive Express
September 14, 2004 6:28 AM
Filed Under: BMW, German
Press Release
(BMW M5 In Depth - Part 1)
The BMW M5 engine production: Engine construction at its best
The highlights:
- Highly flexible production line with a wide range of products at the BMW Plant in Munich,
- Qualified staff and flexible processes,
- Quality assurance by means of data transfer,
- The highest quality standards.
Core components from the production network.
The cylinder heads and the crankcase for the new V10 engine are produced at the light alloy foundry at BMW's Landshut plant, which also produces parts and components for the BMW Formula 1 engines.Due to the heavy strain on the high-revving aggregate, demands on the surface quality and the manufacturing tolerances are extremely high in mechanical processing at the BMW plant in Munich. For example, components are processed at an accuracy of up to 1∕1000 millimetres. By comparison: a human hair is 0.05 millimetres in diameter (50∕1000).
Flexible assembly.
Final assembly, a highly flexible process, is performed in a two-shift pattern in the so-called special-purpose engine department of the Munich plant, where, in addition to the V10 engine, they also produce the six-cylinder aggregate for the M3, the V8 diesel and the twelve-cylinder for the BMW 7 model series.
This diversity calls for a great deal of flexibility, profound product
knowledge and excellent skills. This is why the staff responsible for
BMW engine construction are all well-trained and experienced.
As this engine is not a high-volume product, full automation of the assembly processes only makes sense to a certain limited extent. This is why operations carried out manually and automated assembly processes are combined to complement each other perfectly.
An ergonomic work environment, devices for pivoting and swivelling
the engine as well as for handling heavy loads ensure optimum working conditions and constitute the basis for supreme product quality.
As part of quality control, both the water chamber and the depressurised oil chamber of every single engine are checked for leakages, followed by hot run testing on the engine test bed.
Core components such as cylinder heads or connecting rods are provided with a code, which enables the staff to keep track of each component from the very moment it reaches the factory to mechanical processing through to its installation in the engine.
At work stations where complexity is particularly high, the monitors display which of the colour-coded crankshaft bearing shells has to be inserted.
The two-piece crankcase renders it necessary to use a special sealing technique. A sealant is injected fully automatically into the sealing surface via a circumferential groove. As soon as the sealant comes out at the other end, it is hardened at that particular point by means of UV light. The sealant in the interior hardens as the assembly process continues.
The specialist engines are made to order, meaning that the customer-specific assembly does not start before the receipt of an order from one of the vehicle plants. Depending on the specifications, it takes up to 24 hours for an engine to pass through all stages of the assembly process.
A sophisticated logistics system – BMW’s Customer-Oriented Sales and Production Process (COSP) – ensures that each car is built exactly on time to its specific national specifications and, of course, in line with the customer’s personal order and requests.
Quality management systems consistently optimised and upgraded,
together with numerous function and reliability tests in all areas of production, guarantee optimum fulfilment of BMW’s strict quality requirements.
Production of specific parts and components exclusive to the M5 is integrated in the production processes and production areas as such. The floorpan,
for example, fitted at the rear of the car is modified to provide space for the double-chamber exhaust system. Reinforcements around the rear axle
subframe, in turn, serve to accommodate the extra power and performance of the M5. To provide adequate space for the rear wheels, the side-frames have been modified around the rear wheel arches. And, finally, suitably moulded body panels specially made in the press shop are fitted on the side walls.
The joining technologies used in production of the lightweight aluminium
front end are bonding, riveting, MIG and laser welding.
In all, BMW uses some 1,000 robots in production of the 5 Series
(Saloon, Touring, M5) body-in-white. The bodyshell consists of approximately 500 steel and aluminium parts weighing approximately 350 kg.
A particular challenge in the Paintshop is to ensure perfect balance and harmony of colours between the body and individual components such as the bumpers, sills and rear-view mirrors. This efficient process of perfect colour-matching is ensured by new, automatic online measurement of each and every colour shade.
High qualification and motivation of all associates ensure perfect production of customised cars of the highest quality. After all, each and every M5 is tailored to its proud owner – from the drivetrain through the suspension and paintwork all the way to the seats and interior equipment.
Wherever possible the workers on the line are assisted by handling devices picking up and transporting heavy components and thus avoiding heavy
physical labour. As a result, the workers are able to concentrate entirely on the process of fitting the parts and components smoothly and with ultimate precision. In this process they are supported by a special Information System for Associates presenting the parts and components to be fitted in each
case on a screen. And considering the large number of different models built in Dingolfing, together with their wide range of specifications, this is indeed essential.
Special components exclusive to the M5 – the power unit, seats, steering wheel, rear axle, etc – are also delivered to the assembly line in sequence,
just like all other components of the BMW 5 Series in general. A wide range
of tests and inspections as well as a comprehensive test drive on the
dynamometer come as the final point in production of every M5 before the car goes to the customer.
Within BMW’s model range, the M5 is clearly positioned as a thoroughbred sports car combined with all the traditional qualities of a luxurious saloon.
It ranks distinctly above the other models in the 5 Series – in its small but
highly sophisticated market segment, the M5 is the clear leader both in technical terms and in terms of its position and significance in the market:
No other competitor in this segment has been able to even get close to the sales volume of the BMW M5.
The typical owner of an M5 uses his – or her – car every day, mainly on lengthy business trips. 75 per cent of all M5s are run as business cars, most of them on a leasing contract. Annual mileage of an M5 often reaches or even exceeds the 100,000-km mark.
The “average� M5 customer is male, married, and has two further cars in
his household. At an average age of 45, the typical owner of an M5 is several years younger than the “regular� driver of a 5 Series, has a higher level of training and earns an above-average income.
Owners of a BMW M5 are to be found in all self-supporting professions.
They pursue a prestige-oriented and active lifestyle, enjoying sports such as golf, sailing, riding or powerboat cruising, just like exclusive journeys to faraway destinations.
In the meantime other manufacturers have tried to copy this successful
concept created and introduced by BMW. But over the years the BMW M5 has remained by far the most innovative and successful car in its segment.
An appropriate standard of driving safety was ensured by sports suspension tailored to the superior performance of the car with features such as gas-pressure dampers, special 220/55 VR 390 Michelin tyres, extra-large disc brakes, a specially tuned ABS brake system, and a limited-slip differential with 25 per cent locking action fitted as standard.
This very first BMW M5 accelerated from 0–100 km/h in 6.5 seconds
and, at a top speed of 245 km/h or 152 mph, was the fastest saloon in its time. Despite this outstanding performance, fuel consumption was
a mere 11.3 litres of premium on 100 km, equal to 25.0 mpg Imp.
The customer looking for special interior features on his M5 also received professional treatment from BMW Motorsport GmbH, being able to choose from a wide range of features and outstanding options.
Total production of the first-generation M5 in Munich amounted to some 2,200 units all built by hand.
From outside the second-generation M5 was more muscular and personalised than its predecessor, the body of the new model boasting muscular front and rear air dams, side-sills in contrasting colour, and wheels in special design.
The power unit was in principle still the successful engine of the BMW M1 now, however, refined in many respects. One particular highlight was the resonance air chamber adjusting the oscillating pipes for length in the interest of optimum torque as a function of engine load and speed. The control unit used for this purpose was specially developed by BMW M GmbH.
The body of the M5 was lowered by 20 millimetres versus the BMW 535i in the market at the time, and there was an optional Nürburgring suspension package for the particularly sporting driver. A standard feature on the second-generation M5 was self-levelling on the rear axle as well as a differential lock with 25 per cent locking action.
This high-performance saloon cum sports car accelerated to 100 km/h in just 6.3 seconds and had a top speed – electronically limited – of 250 km/h
or 155 mph. Together with the M5 Touring launched in 1992, the second M5, accounting for some 12,000 units built by hand in Munich, outsold its predecessor by far.
These looks were matched by maximum output of 294 kW (400 bhp)
developed by a five-litre V8 power unit ensuring supreme performance on the road: The third-generation M5 accelerated from 0–100 km/h in just
5.3 seconds, reaching 160 km/h in a mere 11.6 seconds. Top speed was
250 km/h or 155 mph, again limited electronically.
Not only the sophisticated technology of the third M5 made this car quite
different from its predecessors, but also the way it was built. For now, like all other models in the 5 Series, the M5 was built on the series production line in Dingolfing, with its power unit coming from BMW’s Special Engine Shop in Munich (and incidentally also featured in the exclusive BMW Z8 Roadster).
Total production of the third-generation M5 was more than 20,000 units.
Quality assurance via data transfer.
The engines are mounted to special devices and to driverless system
carriers that house a data unit which stores the most important production data. During the course of the assembly process, the data unit records
crucial, quality-related data, such as the tightening torques or valve play and stores this data in a database. The data carriers also ensure that the
right program, intended for the engine under construction, is activated at the automated assembly stations. At the assembly stations fitted with integrated tools, data communication ensures that the personnel use the right tools with the correct tightening torques. Skilful craftsmanship: an absolute must.
Particularly when it comes to the pre-assembly of the valve train and the crankshaft drive, experience, meticulousness and skilful craftsmanship are a must. The work on the kinematics of the VANOS variable camshaft control
and the synchronisation of the ten individual throttle butterflies is also very demanding and requires considerable dexterity by the assembly staff. Sophisticated logistics.
The supply of parts and components demands the highest of logistics standards as each of the four engine types with its numerous variants is made of about 400 different parts and components. The associates are an
integral part of this complex process as they must use different parts and tools, depending on the type of engine manufactured. Production of the BMW M5:
Exclusivity off the Line
The BMW M5 is built at the Dingolfing Plant, the largest production
plant within the BMW Group’s production network comprising no less than
23 production facilities worldwide. Highly flexible in all its operations,
the Dingolfing Plant employs a workforce of approximately 23,000 BMW associates – thereof more than 80 per cent skilled workers – and builds
some 1,300 BMW 5, 6, and 7 Series every day.
Production of the body-in-white together with other models
in the 5 Series.
The body-in-white of the new M5 is built by highly flexible robots on the same lines and facilities which also produce the bodyshells of the BMW 5 Series Saloon and the BMW 5 Series Touring in the regular production process. This course of production takes place in any random order and combination in accordance with instructions from production management. Naturally, the bodyshell of the M5 also benefits from all the innovative bonding and joining technologies used in series production of the BMW 5 Series. This also applies to the application of stamp rivet technology on the lightweight aluminium front end of the car. Offering the customer a wide range of – sometimes quite unusual – paintwork colours.
In the Paintshop the body-in-white of the M5 goes through all the systematic processes already applied in the regular paintwork process. First there is the RoDip (Rotation and Dipping) pre-treatment process allowing a share
of up to 30 per cent aluminium. Then anti-corrosion paint is applied on to the
phosphated bodyshells in the cathodic dip bath (CDB) both inside and outside, extending all the way into the smallest nooks and crannies. Following application of the filler by means of all-new robot paint-application technologies, the body of the car is finished in BMW’s new, exclusive M colours on a special paint application line. This ensures a perfect finish in the four M colours as well as a wide range of some 250 individual colours all naturally applied in top quality to fulfil all of the customer’s requests very flexibly and efficiently. The powder-based clear paint applied as the final layer gives the surface an appropriate gloss and protects it from both ultra-violet radiation as well as other elements in the environment. Human performance – the No 1 factor on the assembly line.
Contrary to job requirements and working conditions in the Press Shop, Bodyshop or Paintshop, where processes are largely automated, human performance is the fundamental factor in Assembly. The reason, quite simply, is that the human being is able to work in almost 30 different modes
and levels with his hands, while even the most sophisticated and advanced industrial robot is not able to operate on more than 7 levels or planes. Market Position of the BMW M5:
The Executive Express
Just like its predecessor, the new BMW M5 is most certainly a genuine
Executive Express. Indeed, this exclusive car defined and opened up
a new niche in the market exactly 20 years ago, creating the segment of the high-performance sports saloon. The History of the BMW M5:
Opening up a New Class
The story of the BMW M5 now dates back 20 years: Back in 1984 a group
of inventive engineers and marketing strategists at BMW Motorsport GmbH,
as the Company was still called at the time, had the idea of transplanting
a muscular high-performance power unit into a relatively “normal-looking�
saloon, in this way creating an entirely new type of car – the high-performance sports saloon. The first generation of the BMW M5: from 1984–1987.
Back in the mid-80s there were already demanding BMW customers looking for the power and performance of a sports car within the engine bay of
a saloon, thus enjoying a superior thrill of motoring in sheep’s clothing. And BMW Motorsport GmbH had all the ingredients required for making such
a special car reality: First and foremost, the 210 kW (286 bhp) straight-six power unit once featured of BMW’s legendary M1 mid-engine sports car, and of course the bodyshell of the then current BMW 5 Series. The second generation of the M5: from 1988–1995.
Developing maximum output of 250 kW or 340 bhp, the successor to the
first model featured one of the most powerful straight-six engines ever built by BMW by the end of its lifecycle. And right from the start the second-
generation M5 had entered the market with engine output of 232 kW or
315 bhp, obviously creating a tremendous stir in the process. The third generation of the M5: from 1998–2003.
Introducing this model, BMW made the more reserved design of this
high-performance saloon a lot more athletic, muscular and self-confident.
Now powerful front and rear air dams, broad side-sills, aerodynamically contoured M rear-view mirrors, 18-inch wheels in double-spoke design, as well as four tailpipes clearly bore testimony to this outstanding power machine.