CNHTC, the leading Chinese manufacturer of heavy duty trucks, required a stable, high performance and durable air cleaner system. MANN+HUMMEL developed a customized solution which impresses with maximum performance.

The requirements from the China National Heavy Duty Truck Group (CNHTC) for the air cleaner system to be used in its heavy duty trucks were a low pressure drop, excellent dust holding capacity and a long service interval. A high air flow rate of 36.7 m³/min is the reason why these requirements are necessary. The vehicles are also used in mines with extremely high dust levels. This was no easy task, but MANN+HUMMEL developed a system with two separate air filter elements and in this way fulfilled all of the requirements of the customer.

Maximum stability

Thanks to the used cellulose filter media the filter elements achieve a high dust holding capacity of nine kilograms of coarse dust. With two cyclones fitted upstream the dust pre-separation is significantly increased and in combination with the two filter elements the service life is more than doubled even under extremely dusty conditions. Furthermore, the two safety elements protect the clean air side against dirt particles during servicing or when a main filter element is damaged. The filter housing made from PP-GF30 was specially developed for CNHTC and is produced by MANN+HUMMEL in China using an injection molding process. Regarding the integration of functions, the filtration and plastics specialist also came up with an ingenious solution. MANN+HUMMEL designed the housing with numerous ribs and reinforcement elements to ensure maximum stability. This includes three reinforcement rings located in the area of the two air inlets and the air outlet. Additionally a rod-shaped reinforcement made in plastic supports. The rod is fixed between the filter elements to both sides of the housing. A further design feature of the system is a gathering duct which combines the cleaned air from the elements and directs it to the air flow meter.

Playing safe

A number of other components also improve reliability. The water discharge valve on the lower side of the housing prevents the accumulation of an excessive amount of water inside the housing. A seal between the service cover and housing also protects against the intake of warm air, dirt and water. Finally, mounting points on three sides of the housing enable flexible mounting of the air cleaner to the vehicle. The development at the Chinese locations of Changchun and Shanghai and the local production enabled an excellent cooperation between CNHTC and MANN+HUMMEL.