This is how Rheinmetall technology balances excess or negative pressure in the fuel tank system
New valves for fuel vapor retention in EVAP systems
Restraint systems for fuel vapors, so-called EVAP systems, are now common components of modern combustion engines. In today's hybrid vehicles, the fuel tank system is sealed off from the outside and so excess or negative pressure can build up. Yet in certain situations this pressure must be balanced out again. Pierburg has developed two new valves for this purpose: both the Fuel Tank Isolation Valve (FTIV) and the Fuel Vapor Valve (FVV) are based on a modular system.
The FTIV is normally placed between the fuel tank and the activated carbon filter and controls the flow to the filter. In addition, additional valves are required to open and close the complete system, for example during OBDII tests. The FTIV is a normally closed valve that can be opened electrically as required. It has two mechanical bypasses which reduce the built up pressure or underpressure as soon as a pre-defined threshold is exceeded. In addition, the volume flow of fuel vapors in the direction of the activated carbon filter can be limited to a maximum value by a flow limiter. The valve meets the non-leakage and flow requirements of modern fuel tank systems with a compact design and low weight.
Thanks to the modular build, it is possible to equip the FTIV with any functions required by the customer. For example, there is an option in which the valve is closed without current and only has an overpressure bypass.
Another variant of the valve, the FVV, is normally open. This type can be closed by simply applying power, if desired, so that the path of the fuel vapors in the EVAP system is sealed, for example, during an OBDII test.
Rheinmetall was established in 1889 as Rheinische Metallwaaren- und Maschinenfabrik Aktiengesellschaft. Today, Rheinmetall AG, publicly listed and based in Düsseldorf, is a powerful, internationally successful corporation and is the management holding company of the Rheinmetall Group. As an integrated technology group, Rheinmetall is a market leader in the areas of environmentally friendly mobility and threat-appropriate security technology. The group´s operating activities are split into the two corporate sectors, Rheinmetall Automotive and Rheinmetall Defence. In 2018, its 24,949-strong staff generated annual sales of €6,148 million.
Rheinmetall Automotive AG is the parent company of Rheinmetall’s Automotive sector. As a global first-tier supplier to the automotive industry, Rheinmetall Automotive thanks to its vast capabilities commands foremost positions in the product and component segments air supply, emission control and pumps as well as in the development, manufacture and aftermarket supply of pistons, engine blocks, and plain bearings.
Product engineering and development are conducted in close liaison with the leading car assemblers. Low emissions, reduced fuel consumption, upgraded performance, reliability, quality, and safety - these are forces that drive innovation at Rheinmetall Automotive.
In line with its strategic focus, the Group has three premium brands: Kolbenschmidt, Pierburg und Motorservice and employs a workface of around 11,500 employees at its production locations in Europe, North and South America, Japan, India plus China.