6.3.3. Catalytic converter

Catalytic converter

Gases on an entrance of the catalytic converter and products at its exit

The catalytic converter has the central ceramic part of a cellular design-3-covered with a carrier layer. On a layer of the carrier there are salts of precious metals operating as converters. The catalytic converter is fixed in the case-1-by means of the insulating basic layer-2-compensating at the same time thermal expansions of the catalytic converter.

Left dokataliticheskiya lambda probe

Right dokataliticheskiya lambda probe

Left post-catalytic lambda probe

Right post-catalytic lambda probe

Petrol engines

To reduce harmful emissions by means of the catalytic converter, systems of injection has to dose precisely amount of the injectable fuel necessary for combustion. The sensor of oxygen is in a reception pipe in front of the catalytic converter and is washed by a stream of the fulfilled gases. The sensor of oxygen represents the electronic sensor measuring the content of oxygen in final gases and representing its type of fluctuations of tension. Information from the sensor of oxygen is transferred to the control unit of system of injection. The received value allows to regulate composition of air-petrol mix. On the one hand it is necessary as service conditions constantly change (idling, full gas), on the other hand, as optimum reburning of fuel in the catalyst happens only in this case if final gases contain enough fuel.

That in the catalyst there was a fuel reburning, it is necessary to have temperature of 300 - 800 °C. For this purpose the bigger content of fuel in mix, than is necessary for pure burning.

The used catalytic converters of petrol engines represent so-called three-functional devices. In adjustable process of transformation oxidation of carbon monoxide (SO) and hydrocarbon (NANOSECOND), and also reduction of concentration of nitrogen oxides (NOx) is carried out.

Security measures for an exception of damages of the catalytic converter

For an exception of damages of the sensor of oxygen and the catalytic converter it is necessary to fulfill the following requirements:

Petrol engines

Start of cars with AT is for technical reasons impossible.