CRDI Technology

CRDI Technology (Common Rail Direct Injection)

CRDI is an intelligent way of controlling a diesel engine with use of modern computer systems. CRDI helps to improve the power, performance and reduce harmful emissions from a diesel engine. Conventional Diesel Engines (non-CRDI engines) are sluggish, noisy and  poor in performance compared to a CRDI engine.

CRDI or common rail direct injection system is also sometimes referred to by many similar or different names. Some brands use name CRDe / DICOR / Turbojet / DDIS / TDI etc. All these systems work on same principles with slight variations and enhancements here and there.

CRDI system uses common rail which is like one single rail or fuel channel which contains diesel compresses at high pressure. This is a called a common rail because there is one single pump which compresses the diesel and one single rail which contains that compressed fuel. In conventional diesel engines, there will be as many pumps and fuel rails as there are cylinders.

How it works…?

As an example, for a conventional 4 cylinder diesel engine there will be 4 fuel-pumps, 4 fuel rails each feeding to one cylinder. In CRDI, there will be one fuel rail for all 4 cylinders so that the fuel for all the cylinders is pressurized at same pressure.

The fuel is injected into each engine cylinder at a particular time interval based on the position of moving piston inside the cylinder. In a conventional non-CRDI system, this interval and the fuel quantity  was determined by mechanical components, but in a CRDI system this time interval and timing etc are all controlled by a central computer or microprocessor based control system.

To run a CRDI system, the microprocessor works with input from multiple sensors. Based on the input from these sensors, the microprocessor can calculate the precise amount of the diesel and the timing when the diesel should be injected inside the cylinder. Using these calculations, the CRDI control system delivers the right amount of diesel at the right time to allow best possible output with least emissions and least possible  wastage of fuel.

The input sensors include throttle position sensor, crank position sensor, pressure sensor, lambda sensor etc. The use of sensors and microprocessor to control the engine makes most efficient use of the fuel and also improved the power, fuel-economy and performance of the engine by managing it in a much better way.

One more major difference between a CRDI and conventional diesel engine is the way the fuel Injectors are controlled. In case of a conventional Engine, the fuel injectors are controlled by mechanical components to operate the fuel injectors. Use of these mechanical components adds additional noise as there are many moving components in the injector mechanism of a conventional diesel engine. In case of a CRDI engine, the fuel injectors are operated using solenoid valves which operate on electric current and do not require complex and noisy mechanical arrangement to operate the fuel Injection into the cylinder. The solenoid valves are operated by the central microprocessor of the CRDI control system based on the inputs from the sensors used in the system.

So if I summarize it, CRDI works on intelligently controlling the Diesel Engine by using sensors and microprocessors. It replaces some of the mechanical components with intelligent electrical and electronic systems which improves the power, response, efficiency and performance. It also reduces the noise, emissions and vibration levels to a considerable extent

How efficient is a CRDI engine with respect to ordinary diesel engine ?

Traditional diesel engines with injection use pipe style injectors that do not control the flow of fuel. this is done remotely by an injection pump. all its control is mechanical (such as engine revs, load, temp) and it converts this to a timed pulse of varying pressure and therefore volume along individual lines to each 'dumb' injector.

common rail diesels are more like a petrol injected engine. each injector is 'smart'. controlling its own fuel delivery. an electric fuel pump pressurizes fuel to a high pressure. an ecu digitally analyses engine variables such as load, air temp, air pressure, rpm, engine temp, current selected gear, etc) and overlays these values on a map, giving a value of the amount of time the injector stays open. as the fuel is at high pressure, short time = small amount of fuel, and visa-versa. this system works very quickly, allowing for adjustments between cylinders during an engines revolution.

Design Story......

Futuristic styling and new technologies make a ‘stand-out’ vehicle



The original Kia Sorento was a ‘landmark’ vehicle which took the Korean brand into a whole new section of the automotive market all around the world. Introduced in 2002, it marked a huge step for Kia, challenging many established 4x4 and SUV brands and starting the process of changing public perception of Kia as a ‘maker of small cars.’

Sorento earned widespread media and public acclaim for its innovative styling, durability, off-road abilities and value-for-money. Over the next seven years, it attracted thousands of customers who had not previously considered buying a Kia, and achieved global sales of almost 900,000 units. It also paved the way for the successful introduction of the smaller Kia Sportage.

At its launch, the original Kia Sorento injected fresh visual excitement into its segment with ‘stand-out’ looks. Now, under the direction of Kia’s Chief Design Officer (CDO), Peter Schreyer, the Kia design team aimed to deliver futuristic styling with a bold sense of power and dynamism, to once again differentiate Kia’s larger CUV (Crossover Utility Vehicle) from potential rivals by incorporating Kia’s new design DNA.

During development of the 2010 Kia Sorento, Kia engineers ditched the old body-on-frame structure and designed an all-new unitary (monocoque) bodyshell with room for up to seven occupants.

Building on those new foundations, they concentrated on eight key areas – class-leading performance, increased fuel economy, reduced emissions, improved on-road handling, more fun-to-drive responsiveness, greater cabin space and comfort, enhanced overall safety and the introduction of new technologies.

“With the new Sorento, we have created an all-new, seven-seater CUV that will soon be recognized as an ‘exciting all-rounder’ with a much broader customer appeal,” commented Hyoung-Keun Lee, Senior Executive Vice President & COO of the International Business Division. “Despite the current economic uncertainties, we are confident that 2010 Kia Sorento will significantly increase Kia’s share of the CUV market, achieving annual global sales of 140,000 units from 2010.”

The new, longer bodyshell created for 2010 Kia Sorento, with its repositioned A-pillars and dashboard (moved forwards) and extended tailgate (moved rearwards), ensures that the cabin is much more spacious than the current model. The real and perceived quality of the cabin is greatly enhanced and available high-tech features will include: keyless entry, engine start button, reversing safety camera, built-in sat-nav and panoramic glass sunroof.

As part of Kia’s drive to expand market coverage with its latest CUV, the new Sorento will be manufactured with a total of four engines – different engines being available in different regions around the world to best suit local requirements – with CO2 emissions from just 173 g/km.

Introducing a bold sense of power and dynamism

Longer and lower, the 2010 Kia Sorento brings sleek styling and a futuristic touch to the world of the urban CUV. With its longer front overhang, wedge profile, crisply defined greenhouse and accentuated wheelarch volumes, Kia’s new CUV looks thoroughly modern and sporty. The 4.7-metre long new Sorento moves vehicle design in this segment up to a new level of sophistication.

“The dynamic design of 2010 Kia Sorento adopts simple, linear lines to create a powerful, yet polished appearance. Both sporty and striking, new Sorento represents a new breed of vehicle,” comments Peter Schreyer, CDO of Kia Motors Corporation.

Bold frontal styling incorporates Kia’s new ‘signature grille’ that blends seamlessly into the 2010 Kia Sorento’s four-light, black bezel wrap-around headlamps. The profile’s rising upper belt-line and the dynamic bevel treatment beneath the greenhouse (echoing the new Cerato/Forte), plus the unique trapezoid C-Pillar adds tension and endows new Sorento with a unique appearance. Extending the rear window to the outer edges of the simply styled tailgate hints at the spacious cabin and the large tail lamps enhance the sporty appearance.

High-quality trim and high-tech features enhance interior

The 2010 Kia Sorento’s interior styling echoes the sense of power and dynamism created by the exterior appearance. Kia is confident that existing Sorento owners and new customers will be equally impressed by the cabin’s generous proportions, sweeping dashboard design, high-quality fit, discreet trim accents and the availability of numerous high-tech features.

The thick-rimmed three-spoke steering wheel is becoming a Kia trademark feature and through it the driver can view another element of Kia’s developing design DNA – the ‘three-cylinder’ instrument cluster. Similar to the cluster fitted to the 2009 Kia Magentis (Optima), new Kia Soul and new Kia Cerato (Forte), the new Sorento’s cluster has clear and precise graphics.

Depending on model, 2010 Kia Sorento will be equipped with a six, eight or 10-speaker audio system, with MP3 and iPod connectivity, plus built-in or external amplifier and a new sat-nav system with a 6.5-inch screen. Remote controls for the audio system are mounted on the steering wheel.

Versatile seating for seven and more cabin space for all

The longer bodyshell created for new Sorento ensures that the stretched cabin is much more spacious than the current model, with seating for up to seven people. Occupants in all three seat rows benefit from greater legroom, headroom and shoulder room. There is much more space for occupants seated in the third row – headroom is increased by 64 mm (to 906 mm) and legroom by 102 mm (to 795 mm). Luggage space in 2010 Kia Sorento is among the best-in-class as cargo capacity is increased by 15%, thanks to moving the tailgate back by almost 70 mm.

Skilful structural engineering minimizes NVH

During the design and engineering process to create 2010 Kia Sorento, Kia’s research and development team prioritized achieving a major improvement in the vehicle’s refinement and minimizing its noise, vibration and harshness (NVH). An excellent foundation for creating a vehicle with good NVH qualities is a stiff bodyshell structure and the 2010 Kia Sorento features a much higher percentage (70.4%) of high-tensile strength steel compared to the previous model (40.0%).

New LPG engine for Korea and a new diesel for the world

Kia’s all-new Sorento will be manufactured with up to four different engines to meet the needs of motorists in every region of the globe. For the Korean market, Kia is offering the 2010 Kia Sorento with three engines, including a version of its 2.7-litre V6 engine running on low-cost LPG (liquefied petroleum gas) called the ‘Mu LPI’. This unit delivers 165 ps and 244 Nm – the reduced outputs a consequence of using LPG which contains 25% less ‘stored energy’. New Sorento will also be available in the Korean market with the four-cylinder 2.4-litre Theta II gasoline engine that delivers 175 ps and 225 Nm, as well as the new four-cylinder R2.2 diesel engine.

New diesels demonstrate world-class Kia engineering skills

The all-new ‘R’ family of turbo-diesel engines proves that Kia’s engineering capabilities are indeed world-class. The 2.2-litre engine comfortably out-performs most four-cylinder and many V6 units from rival brands, while complying with Euro5 emissions standards thanks to their third-generation common-rail fuel system. The R2.2 generates a maximum of 197 ps and 435 Nm.

New six-speed gearboxes, plus choice of 2WD or 4WD systems

2010 Kia Sorento buyers will be offered a wide choice of transmissions and drivetrains – depending on model. Five-speed and six-speed (manual and automatic) transmissions will be offered. Both the six-speed transmissions are new or upgraded.

Kia’s all-new six-speed automatic transmission is a regular ‘torque converter’ automatic, but it incorporates a unique ‘flat’ torque converter (which allows the unit to be 54 mm shorter), has 62 fewer parts (than a five-speed unit), weighs 12 kilos less and boosts fuel economy by up to 12%.

The 2WD drivetrain offers lower weight and enhanced fuel economy, while the 4WD drivetrain will be ideal for buyers who regularly face difficult driving conditions, tow trailers (weighing up to 2,500 kilos, depending on model) or go off-road.

Traction is also boosted by the available HAC (Hill-start Assist Control) which prevents slipping backwards, and DBC (Down-hill Brake Control) which limits vehicle speed to just 8 km/h (5 mph) on steep declines.

Improved on-road performance, retained off-road capabilities

For new Sorento the suspension engineer’s brief was to shift the handling bias a little to improve the on-road driving experience, in terms of ride quality and steering ‘feel’ – while retaining the vast majority of the previous model’s off-road abilities. The suspension has been lowered by 10 mm and thanks to the new unitary (monocoque) bodyshell construction the centre of gravity has been lowered by 54 mm.

The MacPherson strut front and multi-link rear suspension is ‘carried over’ from the previous model, but with significant improvements. The steering is now more direct (6% faster), requiring fewer turns of the wheel lock-to-lock.

For maximum stopping power, all 2010 Kia Sorento models are equipped with an all-disc braking system. Either as standard or an option, ABS anti-lock and EBD brake force distribution systems are available.

Advanced ‘active’ and ‘passive’ safety systems

2010 Kia Sorento presents buyers with a range of state-of-the-art safety systems and equipment as standard or as options – depending on market. Active safety technologies that buyers can specify include ESC, HAC, DBC, TPMS (Tire Pressure Monitoring System) and RPAS (Rear Parking Assist System), plus several systems to boost braking performance during extreme conditions.

Reversing is made even safer by a new Kia Reversing Safety Camera mounted on the tailgate. This camera is fitted with a 130 degree wide-angle lens and transmits images to a 3.5-inch LCD display panel set within the cabin’s rear view mirror whenever reverse gear is selected.

Maximising protection with ‘passive’ safety technology

New Sorento’s robust all-new bodyshell structure delivers increased impact resistance. Using a much higher percentage (70.4%) of high-tensile strength steel the new vehicle achieves excellent rigidity and strength. Particular attention was paid to the B-pillar areas, with a roll-over hoop incorporated into the B-pillars and much stronger (60 kg grade) steel is used in the side sills.

The new Sorento bodyshell is designed to achieve the top-score 5-Star rating in Europe’s EuroNCAP and the USA’s current official NHTSA crash tests, plus a ‘Good’ rating (again the top-score) in IIHS tests for both frontal and side impacts.

TECHNICAL SPECIFICATIONS

New Kia Sorento

Body & Chassis

Five-door, five-seater, with new all-steel unitary construction bodyshell. Depending on market, choice of four transversely-mounted gasoline and diesel engines, driving the front or front & rear wheels via a five- or six-speed manual or five- or six-speed automatic transmission with Sport Mode (depending on model).

Engines (availability will vary by region and individual markets)

3.5-litre / 277 ps Gasoline (USA, Canada, Australia, Middle East & Africa, General Markets)

Name Lambda 2
Type Quad-overhead camshaft, six-cylinder in V, with dual CVVT
Capacity 3.5-litres, 3470 cc
Max power 277 ps (206 kW) @ 6300 rpm
Max torque 335 Nm (34.2 kg.m) @ 5000 rpm

2.7-litre / 165 ps LPG(Korea)
Name Mu LPI
Type Quad-overhead camshaft, six-cylinder in V, with dual CVVT
Capacity 2.7-litres, 2656 cc
Max power 165 ps (121 kW) @ 6300 rpm
Max torque 244 Nm (25.0 kg.m) @ 4000 rpm

2.4-litre / 174 ps Gasoline (Korea, USA, Europe, Canada, Middle East & Africa, General Markets)
Name Theta II
Type DOHC, four-cylinder in line, with dual CVVT
Capacity 2.4-litres, 2349 cc
Max power 174 ps (129 kW) @ 6000 rpm
Max torque 225 Nm (23.0 kg.m) @ 3750 rpm

2.2-litre / 197 ps Diesel(Korea, Europe, Middle East & Africa, General Markets)
Name R2.2
Type DOHC, four-cylinder in line, with VGT
Capacity 2.2-litres, 2199 cc
Max power 197 ps (147 kW) @ 3800 rpm
Max torque 435 Nm (43.0 kg.m) @ 1800-to-2500 rpm

Transmissions

Choice of five-speed and six-speed manual and automatic transmissions (depending on model and market).

Drivetrains

Choice of 2WD (front-wheel drive) or 4WD with electronically controlled single ratio (High) system that delivers 100% of torque to front wheels during normal road driving. Manually selected ‘Lock Mode’ splits torque 50/50 between the front and rear axles for enhanced stability during slippery conditions (up to 40 km/h).