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Avoid hard NOx

The principal function of the exhaust gas recirculation ‘EGR system’ is to reduce the amount of nitrogen oxides, also called NOx or pollutants, that are produced during the combustion process.

Today, 100 % of the Diesel cars are equipped with EGR valves and currently only 30 % of petrol cars. Since Euro 5, most of the new petrol cars in the market are/will be equipped with an EGR system. New models will be equipped with two EGR types (low pressure and high pressure).

100% of diesel engines in Europe are fitted with an EGR valve

Reduces pollutants to meet Euro norms

60% market coverage – and growing

Comprehensive technical support

EGR Valves Types

There are three basic types of EGR valves. Pneumatic EGR valves have a vacuum controlled diaphragm. These valves can enable a higher flow rate that is required by newer diesel applications. Electric EGR valves are controlled through integrated electronics. These valves are run directly by the engine’s control unit and can be much more precisely regulated. And then there are electric EGR valves that have a cooling unit to further reduce the temperature of the exhaust gases

The new range has the same high quality like all the other products that Niterra are renowned for. To ensure this, all our valve types have undergone and passed testing carried out in extreme conditions. This includes thermal shock testing in temperatures ranging from -40°C to 150°C, tests on valve, cavity and cooling leakage, as well as electrical resistance and lifecycle.


One exhaust gas recirculation product on a rubber drawer in a garage

How do EGR Valves work?

Nitrogen oxides (NOx) are produced during the combustion process. NOx is created when high combustion temperatures enable the nitrogen and oxygen present in the air-fuel mixture to combine. To reduce these harmful emissions the EGR valve takes exhaust gases from the exhaust manifold and reintroduces them into the intake manifold, mixing them with fresh air. This has a double effect, reducing the amount of oxygen in the air-fuel mixture and reducing the temperature, and thereby reducing the amount of NOx the engine produces.

Achieving the “right” level of return gas is governed by the Engine Management System (EMS) which measures various inputs e.g. engine load, engine speed, boost pressure, mass air flow rate, intake air temperature.     

  1. The Engine Management System (EMS) calculates the desired EGR return rate. (Diesel max. 30% and petrol up to 18%)   
  2.  The EGR valve, whch is controlled and actuated by the ECU then returns the exact amount of exhaust gas to the intake manifold as calculated by the EMS   
  3.  The result? NOx emissions are reduced


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