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How are the injectors on a common rail system controlled?

Posted on by Arif Clayton

How are the injectors on a common rail system controlled?

Abstract: In the common rail system, fuel is distributed to the injectors from a high pressure accumulator, called the rail. The rail is fed by a high pressure fuel pump. The pressure in the rail, as well as the start and end of the signal that activates the injector for each cylinder are electronically controlled.

How are the injectors activated in a modern common rail fuel injection system?

Explanation: The fuel injectors present in the modern common rail fuel system are activated by the solenoid valve. Solenoid valves and the fuel pump are electronically controlled. Thus, the common rail serves as the high-pressure reservoir independent of the engine speed.

What type of injectors are used in a diesel common rail system?

Common rail system injectors have to be designed to achieve high accuracy in both fuel quantity and start of injection timing. Common rail systems can use one of several injector designs: servo controlled electrohydraulic injectors, servo controlled electrohydraulic injectors incorporating pressure amplification, or.

Is the injector of a common rail system mechanically or electrically controlled?

In the mechanical incarnation of common rail, the injectors are actuated by overhead cam or rocker arm mechanisms. In modern, electronically controlled systems, such as that in Figure 6, the injectors are actuated by electrically actuated valves.

What is better common rail or direct injection?

A common rail is one of the most important components in a diesel and gasoline direct injection system. The main advantages of the common rail direct fuel injection can be summarized in reduction of exhaust and noise emissions, better fuel efficiency and improved overall engine performance.

What is the difference between direct injection and port injection?

Port injection sprays fuel into the intake ports, where it mixes with the incoming air. With direct injection, the injectors are in the cylinder head and spray fuel directly into the combustion chamber, mixing with the air charge. The intake only supplies air to the combustion chamber with direct injection.

Is the TDI engine good?

The VW Golf TDI uses diesel fuel and gets a consistent 46-48 mpg in mixed driving. The main reason I purchased the VW Golf TDI is that with the diesel engine, life expectancy is 50-80% longer. A well-maintained diesel engine can easily go 400-500,000 miles.

Is CRDi a diesel engine?

Common rail is a fuel injection system found in modern diesel engines. Common rail systems provide a level of flexibility which can be exploited for class leading emission control, power and fuel consumption.

What are the common problems in common rail injection system?

In fact, one of the leading causes of failure in common rail systems is fuel contamination, yet it is one of the most frequently overlooked. If you notice a decrease in fuel economy and think it might be due to a problem with your common rail fuel injectors, you might want to have your fuel quality tested. In the end, your fuel injection type is decided by the type of engine you have, and you’re limited by the modifications made to that engine and its components.

How does a common rail injector work?

The common rail-fuel-injectors are controlled by the vehicle’s Engine Control Unit. When the injectors are activated by the ECU via a signal, a hydraulic valve made up of a plunger or nozzle, either hydraulically or mechanically, opens and sends fuel into the engine cylinders.

What does common rail injector failure mean?

Common rail injector failure is usually sudden and will stop the engine for no apparent reason . The solenoid in the injector being the weakest part is usually the culprit, and can allow fuel to enter the cylinder unregulated. Often the injection pump cannot maintain fuel rail pressure and the engine will shut down due to the ECU fail safe program.

What is common rail direct injection?

Common rail. Common-rail direct fuel injection is a direct fuel injection system for diesel engines. On diesel engines, it features a high-pressure (over 100 bar or 10 MPa or 1,500 psi) fuel rail feeding solenoid valves, as opposed to a low-pressure fuel pump feeding unit injectors (or pump nozzles).

How are the injectors on a common rail system controlled?

Posted on by Arif Clayton

How are the injectors on a common rail system controlled?

Abstract: In the common rail system, fuel is distributed to the injectors from a high pressure accumulator, called the rail. The rail is fed by a high pressure fuel pump. The pressure in the rail, as well as the start and end of the signal that activates the injector for each cylinder are electronically controlled.

How many types of common rail injection system are there?

Two common types
Two common types include the unit-injection system and the distributor/inline-pump systems. While these older systems provide accurate fuel quantity and injection timing control, they are limited by several factors: They are cam driven, and injection pressure is proportional to engine speed.

Do common rail injectors need coding?

Common rail injectors of all brands require coding of the unique calibration code (found on the injector) to the engine ECU.

What type of injectors are used in a common rail fuel injection system?

Common rail systems can use one of several injector designs: servo controlled electrohydraulic injectors, servo controlled electrohydraulic injectors incorporating pressure amplification, or. direct acting injectors.

What is Mpfi and Crdi?

CRDi (Common Rail Direct Injection) and MPFi (Multipoint fuel Injection) are intelligent ways of controlling the diesel and petrol engines respectively with the help of modern computer systems. CRDi and MPfi help to improve the power, performance and reduce harmful emissions from a car engine.

What is common rail technology?

Common rail technology is a digitally controlled, high-pressure fuel injection and sensor system that optimizes engine efficiency & performance. This results in reduced emissions, minimal noise, and peak power output, significantly improving the engine’s overall efficiency and comfort onboard.

What is CRDi technology?

The term CRDi stands for Common Rail Direct Injection. The technology directly injects fuel into the cylinders of a diesel engine through a single, common line, known as the common rail. The common rail is connected to all the fuel injectors.

Why do common rail diesel injectors need to be adjusted or calibrated individually?

Slight difference between target flow and actual flow can occur due to high operating pressures. Certain common rail diesel fuel injectors require calibration during manufacture or overhaul on a specialised diesel injection test rig to produce a data code relating to the characteristics of each individual injector.

What is calibration in fuel injection pump?

A method of calibrating the injectors of an injection system for an internal combustion engine which can compensate for the different flow rates of the injectors fitted in the engine, which are due to the production tolerances of the injectors, in order to re-match the injectors with consequent balancing of the …

How does the common rail injection system work?

When fuel is to be injected into a cylinder, the system opens the nozzle of the relevant injector and the fuel flows from the rail into the combustion chamber, is atomized by the high pressure in the process, and mixes with the air. The common rail system components have to be extremely precisely and flexibly controlled.

When did MTU start common rail injection system?

In 1996, mtu equipped the Series 4000, the first large diesel engine, with a common rail system as a standard feature. A common fuel pipeline — the so-called rail that gives the system its name — supplies all the engine’s fuel injectors with fuel.

What are the components of a common rail diesel system?

Common Rail Diesel systems can now grant maximum performances and reliability to automotive engines, reducing noise and emissions. The system is composed of an injection pump, the rail, injectors and sensors which detect the operating conditions of the engine for a centralized electronic unit (ECU) which manages all the components.

Can a common rail system run with constant pressure?

It should be noted that while common rail systems could operate with maximum rail pressure held constant over a wide range of engine speeds and loads, this is rarely done.