A renowned international carmaker has awarded Rheinmetall Automotive AG, part of technology group Rheinmetall AG, a major order for electrical vacuum pumps. The order extends to a lifetime volume of €250 million. The components will be manufactured by Pierburg Huayu Pump Technology (PHP), a Shanghai- based joint venture company of Rheinmetall Automotive.
The ramp-up phase of production already started last year. The pumps being installed in plug-in hybrid electric vehicles (PHEV) in the Chinese plants of the customer. After lowering production volume during March and April 2020 as a result of the coronavirus outbreak, the Shanghai plant of PHP actually is 100% operational and the customer demand for the pumps is nearly on schedule again.
The electrical vacuum pump has been developed by Pierburg in Germany, where the production already started in 2017 for another order of the same customer. Major advantage of electrical vacuum pumps is that they can be switched off when there is no braking maneuver, while mechanical vacuum pumps run continuously in vehicle operation even when there is no need. Furthermore, the electrical vacuum pump is not connected to the engine oil lubrication system. The oil pump can therefore be made smaller, which in turn increases the efficiency of the drivetrain.
In hybrids, electric vacuum pumps permit to drive purely electrically when the combustion engine is switched off, as full braking power assistance is retained. They also allow the so-called coasting operating mode, in which the engine is shut down and decoupled in order to achieve additional energy savings due to the reduced friction in the drivetrain (extended start / stop operation).
The pumps can as well be used in fully electric vehicles and even in conventional drivetrains. Especially for today's downsized gasoline engines, the electric pumps are also indispensable since they always guarantee an adequate vacuum level, for example for boosting braking power.
In addition to a substantial lowering of fuel consumption and emissions, the pump shows an excellent NVH (noise, vibration and harshness) performance. Mainly in quietly running electric and hybrid vehicles, the noise level of the pump system has to be so low that it cannot be heard while driving. The pump and the integrated motor are completely in-house developments by Rheinmetall Automotive, which led to fastening solutions that enable the electric vacuum pump to be attached to body parts independent from other assemblies and without causing disturbing vibrations in the structure.