The New Renault dCi 1.6l Diesel Engine

19. Aachener Kolloquium Fahrzeug- und Motorentechnik 2010

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Der neue dCi 130 1,6l Dieselmotor von RENAULT The New RENAULT dCi 130 1.6l Diesel Engine Eric Blanchard, Blanchard , Josselin Visconti, Visconti, Philippe Coblence, Coblence , Fabrice Legrand, Legrand, Fabrice Gautier, Gautier, Mathieu Chevrot, Chevrot, Matthieu Clauet, Clauet , Francois Trochu Renault s.a.s, Rueil Malmaison, France

Summary Renault knows that inflecting drastically fuel consumption and CO2 emissions is vital in today's world. The brand already appears among Europe's best-performing car makers regarding average CO2 emissions, and its sights are now set on ranking among the very firsts. In order to achieve this objective, Renault is currently working on the development of CO2 low-emissions and zero-emission vehicles in a determined bid to introduce as many effective technologies as possible at an affordable price. Its work on powertrains focuses on two main areas: •

•

An unprecedented commitment to the development of comprehensive range of all-electric powertrains. New technologies for conventional powertrains. Renault will release a new generation of turbocharged engines, as well as new automatic transmissions with the following steps: o

o

o

the EDC dual clutch transmission that combines exemplary gearshift quality with lower CO2 emissions for the same fuel consumption as that of a manual gearbox. the new 1.6l dCi 130 Diesel engine that represents a further step in the downsizing strategy of 2.0l diesel engines and will be released next year. 'Modular' TCe gasoline engines scheduled for launch in 2012, will have a range of displacement from 0.9l to1.2l and will be available in threeand four-cylinder form with power outputs ranging from 65 to 85kW (90 to 115hp).

This paper will describe the second important step of Renault CO2 technology roadmap: the forthcoming brand new 1.6l dCi 130 engine. This engine has a maximum torque of 320Nm @ 1750 rpm with maximum power of 96 kW @ 4000 rpm.

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The development was focused on CO2 and TCO (Total Cost of Ownership) reduction. Its CO2 emissions will be 30g/km lower than those of a current 1.9l diesel. Designing a brand new engine base gave us the opportunity to implement state-ofthe-art technologies (thermomanagement, stop&start,…) and to introduce innovative features like low pressure EGR. This was made possible with minimum investment by the use of existing flexible production lines. The new dCi 130 is being co-developed within the framework of Renault-Nissan Alliance and is scheduled for release in 2011. Further developments are already in progress to prepare performance evolution of this engine.

1 Introduction Due to an excellent trade-off between CO 2 level, performance and cost, Diesel engines are very popular in Europe. The increasing pressure on fuel consumption makes also necessary to extend Diesel to other markets, while customers expectation is becoming more and more demanding in terms of comfort, driving pleasure, and quality.


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At the same time and to ensure a sustainable development of the automotive industry, emission regulations will lead to very low levels encouraged by a number of proactive companies which Renault-Nissan Alliance belongs to. In order to be at the top of the competition for the satisfaction of its customers and CO2 emissions, Renault-Nissan Alliance Board has decided, mid. 2008, to develop a brand new L4 Diesel engine family known as R9M. The experience of the now famous Renault-Nissan 2.0l dCi & 3.0l dCi engines and all available technologies at Renault & Nissan have been widely used for the New 1.6l dCi development. The drivers of this development were ranking best-in-class regarding CO2 emissions, fuel consumption and Total Cost of Ownership, and complying with all current and future emissions standards. The first version, 1.6l dCi 130 will be launched in the Renault Scénic and Grand Scénic, confirming Renault pioneer position for the sustainable mobility for all. Other versions are expected on Nissan and Renault vehicles in the coming years, while Euro6 version is scheduled for beginning of 2012.

2 Main characteristics overview 2.1 Modular design R9M has been designed as first step of a new family, trying to minimize the number of necessary modifications for future derived versions for Renault Passenger Car Applications. Typically : •

•

•

•

Euro6 application differs only by after-treatment system, O2 sensor and boost pressure sensor Nissan Passenger Car 2WD application differs only by engine mounting bracket, dual Mass Flywheel and intercooler air ducts Nissan Passenger Car 4WD application differs only from 2WD by DOC-DPF and brackets LCV application: differs only by engine mounting bracket, Dual Mass Flywheel, intercooler air ducts, fix geometry turbocharger and oil cooler

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R9M PC Nissan 4x2

R9M IFEu6

R9M LCV

R9M PC Renault

R9M PC Nissan 4x4

Fig. 1:

Vehicle variations of the R9M

2.2 Characteristics Engine code Cylinder arrangement Displacement (cm3) Bore x stroke (mm) Bore pitch (mm) Compression ratio Max power (kW/rpm) Max torque (N.m /rpm) Camshaft drive Valve Drive Cylinder head / block Crankshaft Connecting rod Intake System Injection system After Treatment system Emission standard Balancing shafts

Fig. 2:

R9M In-line 4 cylinders 1598 80 x 79.5 88 15.4 96 / 4000 320 / 1750 - 2250 DOHC, chain + pinion with mechanical lash adjuster 16v, roller finger follower + hydraulic lash adjuster Aluminum / Cast iron Micro finished forged steel Fractured forged steel VN-Turbocharger + intercooler Common rail 1600 bar + 7 holes solenoid injectors DOC + DPF Euro5, Euro6 ready No

Characteristics of the 1.6l dCi 130


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3 Engineering goals based on customers’ requirement (Fig. 3) C-segment targets for R9M Euro5 have been based on customers requirements as summarized in below spider chart: 1 : Below average 2 : Average 3 : Above average 4 : Top level 5 : Leader

Performance 5 4 Quality Driveability 3 2 1 Packaging 0 Emissions NVH

Fuel consumption TCO

Fig. 3:

Engineering goals based on customers’ requirement

3.1 Performance The maximum power (96kW ie 60kW/l) and maximum torque (320N.m ie 200N.m/l) of the engine are delivered respectively at 4000 rpm and 1750 rpm. The comparison of stabilized torque and power curve between R9M and F9Q Euro5 below shows that although R9M torque is slightly lower than F9Q Euro5 torque at low rpm (1000 – 1250 rpm) because of a displacement disadvantage of 0,3 liter, it is better for higher speeds. 350

110 100

300

90 80

) 250 m . N ( e u q r o T200

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F9Q EU05 Torque R9M Torque

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30

F9Q Euro5 Power R9M Power

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10 1500

2000

2500

3000

3500

Engine Speed (rpm)

Fig. 4:

Full load performance of the 1.6l dCi 130

4000

4500

5000

) W k ( r e w o P

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R9M maximum power (96kw) is one of the highest levels among its competitors with similar displacement. Such a balance between power output and low end torque is the result of the optimization of combustion hardware system, technical definition (turbocharger, 16 valves, variable swirl) and calibration work. More than 80% of maximum torque is reached from 1500 rpm with acceptable smoke level.

3.2 Driveability One of the key issues of new 1.6l Diesel engine development was to achieve an ambitious target of maximum Power (96 kw like replaced Diesel 1.9l dCi F9Q Euro5) while improving drastically Specific Fuel Consumption compared to 1.9l dCi. Furthermore, this was to be done without compromising transient response at low and middle engine speed. By using small inertia turbocharger technical definition, R9M reaches F9Q Euro5 transient response over 1500 rpm, and is even better over 1800 rpm.

Drivability @ low engine speed. Acceleration from 1250 rpm, full load – 2 nd Gear – vehicle : Grand Scenic – comparison R9M vs F9Q Euro5

Fig. 5:

Acceleration from 1750 rpm, full load – 3 rd Gear – vehicle : Grand Scenic – comparison R9M vs F9Q Euro5

Characteristics of the 1.6l dCi 130

One of the critical issues for small turbocharged engines is the tip-in response time at low rpm. R9M offers a straight behaviour for tip in and tip out which complies with customer acceleration pedal expectation. Furthermore, Start & Stop performance has been optimized for customer satisfaction and is today at similar level as its best competitors regarding starting time and quality of Automatic Stop and Automatic Start.


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3.3 Emissions One of the main challenges was to find the good trade off between an ambitious maximum power vs emissions level, especially NOX, with a reasonable fuel injection pressure, since particulate Matter (PM) and HC/CO are handled respectively by a Diesel particulate filter and a platinum-palladium coating Diesel Oxidation catalyst (DOC). This configuration reaches Euro5 regulation Furthermore, only by exchanging the coating of the DOC by a lean NO X trap (LNT) and provided extra sensors to monitor the purge of this system, emissions can meet Euro6 regulations level.

3.4 Fuel consumption, CO2 emissions and TCO The current market situation shows that trends are clearly shifting towards more economical and more efficient engines offering appropriate levels of performance. Consequently, the development of R9M was focused on CO2 and TCO (total cost of ownership) reduction. Its CO2 emissions will be 30g/km lower than those of a current 1.9l diesel. C

B

120 130

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JR5 95

K9K

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) n 160 p I ( 170 x e d 180 n I e 190 c n 200 a m r 210 o f r 220 e P

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JR5 95

JR5 95

R9M Eu5

F9Q Eu5

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-30 g/km CO 2

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JR5 95

M9R

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240 250 105

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g /km CO 2

Fig. 6:

Comparison between R9M and Renault current engines

The road map hereafter was used as a guideline for the development of the engine. It includes all expected benefits from each sub-system of the engine. As a result and combined with vehicle technologies, Grand Scénic with R9M will score below 120g/km of CO2 ie (4,55l/100km) and New Mégane hatchback and Coupé will score below 110 g/km (4,25l/100km), meaning among the best on the market for this range of performance.

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Technologies Downsizing including friction improvement Low pressure EGR Thermo management Variable oil pump Variable swirl Stop & start technology Energy smart management Gear set tuning Fig. 7:

CO2 benefit (%) 5,5 3 1 1 0,5 3 3 3

CO 2 road map

Regarding maintenance cost, no part will be changed before 240.000kms (except oil and filters). Therefore the cost of ownership is cut down by 25% compared to previous engines.

3.5 NVH NVH performance of the engine block has been optimized with respect to Euro5 impact, taking into account the best ratio between cost, value and mass. To achieve this performance, FEM computation and numerical optimization have been widely used at early stage of the project. Booming Noise is at good level on the whole speed range. At low engine speed, a Dual Mass Flywheel (DMF) reduces torque fluctuations on the drive shaft and at high speed, the reduced stroke leads to an improved behavior compared to the replaced 1.9l dCi (downsizing effect). Mid-frequencies: several structure optimizations have been performed on engine block and components in order to achieve good stiffness and significant weight reduction in the meantime. Many simulations on ribs, shapes, lengths of skirts allowed a significant decrease of weight while keeping a good NVH performance. Automatic optimization tools have been applied to exhaust, accessories, and mounting brackets. Their aim is to find an optimal technical solution regarding mass and stiffness compromise. The figure below illustrates the application of this tool for a part of the engine


Packaging allocation 

Fig. 8:

Numerical optimum

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Designed and validated part.

Numerical optimisation process

The overall result is a 10 kg weight reduction with same NVH performance. High frequencies: Turbocharger is equipped with an absorber at compressor output to reduce whistle and wind noise. Rattling noises due to camshafts twin pinions are equipped with mechanical lash adjusters, like 2.0l dCi engine. Radiated noise coming from drive chain is attenuated by the use of a damped cover. High pressure fuel pipes have been designed in accordance with fuel pressure in order to avoid coupling between hydraulic and structural resonances that could result in fuel pipes noises. Heat shields have been designed to reduce HF noises amplification: this includes shape optimization by simulation and choice of a three layers material. 110 105 100 95 ) A ( 90 B d

85 80 75 70 1000

2000

3000

4000

5000

rpm

Fig. 9:

Average Noise level at full load

Combustion noise: Due to Euro5 constraints and an ambitious CO2 target, combustion noise has been considered since the very beginning of the project. Improvements were made on both engine structure design and tuning management. Structure has been optimized by means of structure attenuation concept that allows identifying the main parts contributing to combustion noise radiation. For example, the crankshaft pulley was optimized with specific holes that reduce the radiated noise and remove the cavity resonance effect between the pulley and the drive chain cover. Cylinder pressure excitation has also been managed using multi-injections that help to manage tuning compromises with emissions and fuel consumption.

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3.6 Packaging Length and width of the engine have been optimized in order to comply with Renault and Nissan Alliance C & D platform requirement. Main overall dimensions are as follows: Right View

Left View

Front View

Fig. 10:

Rear View

Major dimensions

Thanks to a very compact engine base design, R9M overall dimensions are no larger than replaced engine. In particular, the integration of innovative devices did not lead to extra space, including: •

Complete post processing + low pressure EGR on exhaust face

•

Thermomanagement components on inlet face

•

This also gives the opportunity to use unchanged interfaces compared to replaced engine; for instance: o

Air inlet system

o

Engine mounting bracket

o

Fuel filter


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3.7 Quality The warranty and reliability objectives have been set part by part, based on state-ofthe-art design standard available for each part. The whole engine level is therefore consistent with the quality top 3 target from Renault Contract 2009.

4 Base engine architecture (design for downsizing) Downsizing concept optimization was a key issue for R9M. In addition to capacity reduction, which brings a first step of friction reduction and efficiency improvement, special attention has been paid to volumetric efficiency, further friction reduction, and thermal transfer performance.

4.1 Cylinder head, bore and stroke A first and natural choice for a high volumetric efficiency is a 4 valves per cylinder cylinder-head. Contrary to M9R, the valves pattern is “0°” (one camshaft for inlet valves, one camshaft for exhaust valves), in order to give more space in a reduced volume for water circulation. Related choice is a transverse water circulation, which allows an efficient cooling for a low pressure drop. R9M bore x stroke are 80 x 79.5 mm. This sizing, rather unusual up-to now for a diesel passenger cars engine, has several benefits. Large bore allows increasing valve diameters; it also gives the necessary space for the design of the cylinder head in accordance with thermo-mechanical constraints due to high specific outputs; furthermore, large piston bowl design is favourable for efficient combustion Short stroke allows reduction in height resulting as a benefit of downsizing concept; it also lowers cylinder block weight and results in low dynamical forces and torques, so that balancing shafts are not necessary.

4.2 Friction 4.2.1 Shaft line and moving parts Crankshaft conrod journal (Ø 48 mm) and main journal (Ø 51.5), as well as bearing width have been chosen at minimal levels in order to reduce friction. Piston-to-bore friction is also reduced because of low mean velocity, as a benefit of short stroke. In addition, a U-Flex oil ring has been chosen as a good compromise between oil consumption and friction; the total radial load of the rings pack being 50 N.

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4.2.2 Oil flow reduction Oil flow has been minimised in crankshaft and cylinder head: •

•

•

•

•

at crankshaft con rod journal, by optimisation of oil drill angular position, at crankshaft main journal, by removing oil feeding slot outside journal bearing, at both crankshaft journals, by reducing bearing clearance (minimum gap and tolerance interval), in cylinder head, by natural de-aeration in oil ramp to hydraulic finger follower stops avoiding a dedicated constant leak for this purpose, at camshaft bearings, by reducing oil drill.

4.2.3 Variable capacity oil pump In order to avoid compressing oil and simply routing it through a relief valve, especially at mid-range and high speed, R9M has been equipped with a variable capacity oil pump, thus enabling to compress the required flow according to required oil pressure. The pump design includes a vane and a rotor, and the regulation is carried out by a simple hydraulic eccentricity balanced stator.

Fig. 11:

Variable oil pump


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4.3 Thermal aspects A downsized engine, with reduced heat transfer surfaces and high specific output, requires a particular performance in cooling system.

4.3.1 Transverse water circulation In order to achieve a good compromise between cooling efficiency and a low pressure drop, R9M features a transverse water circulation, meaning that each cylinder has the same flow pattern, hence same thermal transfer characteristics. In the cylinder head, the water core design is double stage (fig.12-a): •

•

one lower core for cooling fire face, around valves and injector, with optimised flow sections to enhance the coolant velocities and thus heat transfer, one upper core for cooling exhaust duct and exhaust face, and for insulating the oil jacket from thermal loads.

This arrangement results in precisely scaled local velocities, and homogeneous heat exchange coefficients, allowing a very good cooling performance on fire face and hot spots (fig.12-b)

Fig.12:

a (left): Engine water jacket b (right): Heat transfer from water jacket

For the cylinder head, main benefit from this efficient heat transfer occures on fire face temperature, which proves to be very low for such a high specific output

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Fig. 13:


Fire face skin temperature benchmarking

In the cylinder block, transverse circulation results in an homogeneously spread temperature along bore, leading to reduced bore distortions, lower oil consumption thanks to reduced load and friction on piston rings, thus reduced ring wear. The pressure difference between the two sides of the cylinder block water jacket (due to the transverse circulation) provides high flow velocities through the inter-bore drillings, and enhances the efficiency of the inter-bore cooling.

4.3.2 Water flow optimization Good control of water velocities inside the engine enables to reduce water flow to low level. R9M engine shows a low ratio water flow / kW.

R9M

Fig. 14:

Coolant flow vs engine performance benchmarking


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Moreover, transversal flow circulation allows less constraint on cylinder head gasket calibration holes; this strongly contributes to the high permeability of the water system. Combination of a high permeability and low maximum flow results in reducing power absorbed by water pump

5 Systems and components (design for Unique Selling Points) In addition to a design for downsizing, R9M integrated from the beginning optimized systems and ancillaries supporting ambitious engineering goals (USP: fuel consumption, TCO, mass, NVH).

5.1 Fuel consumption In order to achieve R9M engine target - fuel consumption reduced by 20% compared to replaced engine – it has been necessary to use several innovative designs and devices for combustion, emissions after treatment, and thermal behaviour in all conditions.

5.1.1 EGR system + Exhaust system After-treatment system has been located under turbocharger in order to improve efficiency by reducing distance between turbo and catalyst and have enough volume for fitting both DOC and DPF in the same canning. This integration results in: •

•

•

low pressure drop, large volumes (1.9l for DOC and 2.45l for DPF) reducing Total Cost of Ownership even in case of severe usage, compatibility with future emissions regulations by simply adapting DOC specification.

This has been possible by fitting the turbocharger on top of exhaust manifold, and by using plate and clamps for the fixing of catalyst onto the cylinder block. The canning also provides a flange for Low Pressure (LP) EGR system feeding.

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LP EGR system is composed of : •

a water heat exchanger, with integrated filter, fixed on catalyst flange,

•

an electric valve,

•

a mixer located at compressor inlet.

This assembly is fixed on a mounting to cylinder block, and decoupled from catalyst. Special attention has been paid to serviceability An electrically controlled exhaust flap, located on exhaust line, gives back-pressure for routing gases through the system when necessary.

Fig. 15:

High and low pressure EGR system

LP EGR system provides two advantages: •

•

density of re-circulated gases is higher, because they are compressed by turbocharger, efficiency is improved because of lower temperature.

In addition to LP EGR, a more standard High Pressure (HP) EGR system, but without intercooler, also contributes to NOX reduction during engine low temperature phases.


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The electrical valve for HP EGR is fitted directly onto intake manifold, with water cooling using the vent flow from the cylinder head to degassing tank. HP EGR valve is fed through a duct cast inside cylinder head, connected to a fifth branch of exhaust manifold.

5.1.2 Variable swirl Variable swirl enables to improve CO2, NOX and soot over all engine range by monitoring a high swirl level at low engine load and a low swirl level at full engine load. This optimized compromise between swirl and permeability is performed with a single swirl flap and a double plenum: •

•

upper duct of the manifold feeding ‘swirl ports’ in cylinder head, lower duct of the manifold, controlled by the swirl flap, feeding ‘filling ports’ in cylinder head

The double plenum also incorporates HP EGR valve as already described.

Fig. 16:

Variable swirl system

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5.1.3 Thermal management The purpose of the thermal management system is to increase water and oil temperature rise during engine heating, resulting in: •

HC / CO reduction due to higher temperature inside combustion chamber,

•

reduced friction due to higher oil temperature.

The mean for having a quicker rise of fluid temperatures is simply a pneumatically activated ball-type valve that stops the flow through engine (cylinder block + cylinder head), except for the lower part of the engine and EGR cooler in order to allow efficient EGR during warm-up phase. When the internal temperature has reached the required level, the control of the valve ensures it opens in order to comply with engine reliability issues. When the valve is open, cooling returns to the normal operating mode.

Fig. 17:

Thermal management system


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5.2 TCO In addition to fuel saving, both for economy and environment, one major goal of R9M is reduced maintenance cost. This applies in several fields.

5.2.1 Timing chain Timing drive is made through a chain, which does not require any servicing: it lasts vehicle life. The chain is a single one, similar to the one used on M9R

5.2.2 Oil volume / Oil drain interval Oil volume has been sized as: •

•

the minimal possible value, in order to reduce oil drain servicing price, with constraint of oil ageing (oxidation, dilution, carbon content) optimized for high oil drain interval.

Thanks to triple post injection, oil dilution is minimized during DPF regeneration, and reaches very low level, even for extreme customer mission profile such as door to door cycle. The Oil Control System can adapt the oil drain interval to driving conditions and severity. Oil drain interval can reach 40 Kkm / 3 years for passenger cars Furthermore, in order to reduce price repair in case of under car unexpected shock, design provides separate parts for oil sump lower plate (steel sheet cover) and oil sump structural part (cast aluminium).

5.2.3 Ancillaries drive Ancillaries drive is through an EPDM + aramide structure belt, which ensures a 240 Kkm / 10 years life time.

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5.2.4 Air and fuel filters Air filter is derived from 1.5l dCi engine, and gives 80 Kkm / 4 years durability. Fuel filter is new type, with compatibility for pressurized circuit, and allows 120 Kkm / 6 years durability.

5.3 Weight For the whole engine, weight reduction has been considered as a key requirement, with NVH performance and price impacts under control.

5.3.1 Cylinder block and NVH Cylinder block, in cast iron, has been highly optimized in order to reduce its weight: •

•

Cylinder block height benefits from short stroke, and junction with aluminium oil pan has been optimized with respect to NVH behaviour in order to reduce as much as possible cast iron height compared to aluminium; as a result, skirts height is 45 mm, Electric starter is fixed directly on clutch housing, thus avoiding an extra cast iron ear / flange.

As a result, the achieved compromise between bottom engine weight and vibration level illustrates Renault best practice and is better than most of competitors cast iron cylinder blocks. 24 23 22 ) B21 d ( l e v 20 e L n o 19 i t a r b i 18 V

New 1.6 dCi

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85-110kW, IRON CAST Benchmark :

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COMPETITORS RENAULT

15 30

35

40

45

50

55

60

Bottom Engine Weight (kg)

Fig. 18:

Renault representative vibration index vs mass benchmarking


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5.3.2 Plastic parts R9M incorporates many plastic parts: •

Water inlet and outlet manifolds

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Inlet flap bodies (shut-off and swirl)

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Oil filter / cooler module

•

High pressure air ducts from compressor outlet to inlet manifold

•

Water pump pulley

•

Oil separator, Fuel splash cover

Total mass for plastic parts reaches 8 kg and enables a weight reducing of 3.5 kg.

6 Engine Control Unit ECU development of 1.6l dCi benefits from EMS2010 concept, a modular software design by Renault. By using its own rules for specification and coding, Renault is architect for the system and therefore is able to implement the same software modules on electronic platforms of different suppliers. This innovation presents the following advantages: •

a better stability due to a 70 % carry over ratio of software content for 1.5l, 2.0l and 2.3l diesel engines,

•

an optimized time-to-market with 30 % of development time reduction,

•

a better economical performance due to 40% cost reduction.

In the ECU, 80% of software specifications and code are Renault property. Furthermore, scheduling and cost for using new functionalities on future engines will be drastically reduced. New functionalities implemented for R9M include EGR Low Pressure, Variable swirl control, Stop&Start, Thermo-management and Closed-couple CSF management. Hardware resources involve a clock rate of 133MHz and a Flash memory of 2MB.

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7 Quality and reliability To ensure the “top 3” quality level of R9M dCi engine, Design to Quality process has been implemented (Fig. 26). For each part, the quality status has been checked in the field for carry-over parts, and estimated based on most similar parts in case of new parts. For any detected defect, quality improvements were implemented and validated. Amongst the 264 parts references of R9M dCi, 25% are common with other Renault engines. R9M dCi quality is expected to be at the same level as other engines, based on the use of common parts and the same DtQ method as for M9R, that proved to be efficient with less than 0,5 % of customer complains during the first year of warranty. During the development, more than 24 000 hours of durability test on engine test benches have been run. At the same time, more than 550.000 km were driven on vehicle equipped with R9M dCi. Each single problem faced has been understood and solved.

Fig. 19:

Design-to-Quality process

Design to quality Since the preliminary phase of design, the process consists in the evaluation of each engine part and control management system, according to the three categories: 1. New parts and systems (novelty part or system) 2. Carry over of parts or systems with a good production quality level 3. Carry over of parts or systems with a production quality level to be improved


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The exhaustive plan of actions is implemented in 3 steps based on previous evaluation: •

•

Step 1 is to apply the appropriate Quality tools (PHA, P-FTA, FMEA)* for each novelty part or system, to set the influence of each root cause and to validate them. The follow-up of main novelty parts (or systems) development was jointly made with Nissan engineering. Steps 2 and 3 lead to check respectively the implementation of design policies for all parts or systems, then to check the application of all countermeasures applied in production concerning parts or systems of above third category.

(*) PHA: Preliminary Hazard Analysis P-FTA: Perfect Fault Tree Analysis FMEA: Failure Mode Effect Analysis

8 Machining and Assembly plant The chosen assembly plant is Cleon, in France, 100 km west of Paris. Cleon is the main assembly plant for Renault engine and will produce the R9M engine. 6 installations will be used for R9M: •

A new flexible assembly line.

•

Hot test benches on which each engine will be checked.

•

3 Flexible machining lines for Cylinder head, Connecting rod and Crankshaft.

•

A new flexible machining line for Cylinder block.

Cylinder head, Connecting rod and Crankshaft are very close to M9R design, thanks to modular design, so that minor modifications where made on the existing flexible lines which are already producing M9R parts, resulting in low investment and engineering resources. The Cylinder Block machining line is a new flexible line, capable of machining different cast iron cylinder blocks, included in a perimeter of dimensions. Machining centers and Flexible Transfer Machines are at the root of this flexibility. In order to reduce change over time, quick changes of fixtures have been studied with machine suppliers, including for Flexible Transfer Machines. 38% of the installation is based on carry over of existing machines, reducing global investment. Hot tests benches where already installed at Cleon, and only adaptation was to be made (Fig. 20 & 21). 100% of R9M engine will be tested before delivery to vehicle

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plants. Number of benches will exactly match the capacity of assembly line to achieve best level of synchronic delivery to vehicle plant. During the 10’ cycle, the engine is heated up and about ¼ of the maximum load is applied. More than 200 parameters are checked: pressures, temperatures, electric currents and voltages, flows, sensors and actuators functioning, leaks, NVH, Control Unit signals, in order to contribute to the zero defect quality level when the engine is delivered from Cleon. Furthermore, during the engine launch period, the above parameters are recorded for each engine. This will help, in case a defect occurs at vehicle plant or in the field, to increase the checking efficiency of this test procedure.

Fig. 20:

R9M Hot test bench

Fig. 21:

Overview of hot test benches

The assembly line engineering has taken into account from the beginning the constraints to be flexible to any engine definition and the vehicle plant diversity.


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Renault has had a look to eastern to source this line. Benefit has been taken from local Indian engineering center to design and manufacture the line 10000 km far from final location. Pallet has been designed to allow huge access to all faces of engine. An adaptator has been added between pallet and engine to allow flexibility to other kind of product. The pallet has been designed to be unique for the whole assembly line for investments optimization.

Fig. 22:

Assembly pallets

Most of operations are manual, in order to ensure this flexibility. Regarding next step of capacity, some automatic stations will be added according to cost efficiency of the economical balance. The only automatic stations have been designed flexible: robots are mostly used for silicon deposit to reduce impact of following diversities. To reach best level of manpower efficiency, most of the parts assembled on the engine are delivered to the operator by kitting tray. This reduces the non added value of the operator and focuses him only on assembly sequence. Four kinds of kit trays are available at SOP (around 30 parts per kit).

Fig. 23:

Full kitting for dressing sequence

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9 Conclusion R9M family introduces a new generation of Diesel engine which will allow the Renault-Nissan Alliance to remain at the top of the competition in the European market. For this brand new 1.6l dCi engine featuring a power of 96 kW and a torque of 320 Nm, a special focus was set on customer satisfaction including : •

•

•

a 20% breakthrough of CO2 emissions and fuel consumption in comparison with replaced 1.9l dCi 130, positioning R9M as best-in-class for its range of power, best-in-class Total Cost of Ownership features, a “driving pleasure” at the same demanding level as the replaced 1.9l dCi 130, including transient response at low and middle engine speed combined with top level NVH.

This was made possible through several challenges during the development : •

•

•

•

•

the implementation of state-of the art technologies such as highly optimized downsizing, thermomanagement, variable capacity oil pump, variable swirl, stop & start, and the introduction of major innovative features like low pressure EGR. a constant effort for weight optimization during the development process, a modular design approach for a diversity of future Renault and Nissan applications, including. 2WD and 4WD, PC and LCV, Euro5 and Euro6 versions, systematic implementation of Design to Quality and reliability validation, an optimization of flexibility and investment for manufacturing in Cleon Plant, including a new flexible assembly line and reuse with minor modifications of the existing flexible lines of M9R as much as possible.

This achievement is the result of the strong involvement of the relevant divisions within Renault – Nissan Alliance but also the result of the very close relationship with our suppliers.


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10 References [1]

BRUNET, P.; ELLUL, D.; HUET, J. L.; MALCUY, S.; MONEREAU, C.; PIANA, J. The new Renault 2.0 liter Diesel Engine 27th International Vienna Motor Symposium, 2006

[2]

DEMAZURE, C.; AYMARD, C.; BRUN, E.; LE LAGADEC, J. P.; LUSSAULT, D.; REVERSEAU, D.; ROGEZ, D. The new Renault V6 dCi Diesel Engine 17th Aachener Kolloquium Fahrzeug und Motorentechnik, 2008

The New Renault dCi 1.6l Diesel Engine

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