Use Case: Snow groomer

Ventilation drying of hydraulic tanks under extreme environmental influences

GIEBEL Adsorbers® protect the hydraulic tanks of snow groomers and thus ensure reliable operation and long maintenance intervals, even under extreme temperature influences. Why are aeration dryers useful for these machines in particular? And what is the added value of using them?

Snow groomer and operating conditions

Snow groomers, or snow cats, are used to prepare snow slopes and transport people and materials in snowy areas. These machines defy all weather conditions and function reliably even at the lowest temperatures.

Necessity of an adsorber

Due to the large temperature fluctuations between working mode and standstill in a cold winter, there is a high risk for the hydraulic system. For example, the dozer blade, cranes and shapers, and other equipment are supplied by a central hydraulic unit. If this heats up and cools down again frequently, condensation will form in the tank and contaminate the hydraulic oil.

Biodegradable hydraulic oil is used so as not to pollute the environment in the event of leaks. However, these synthetic esters are highly hygroscopic and decompose on contact with water (hydrolysis).

When operating a snow groomer in a ski resort, the temperature is below 0°C. Whereas in the engine compartment, an elevated temperature of 20°C, for example, prevails. At an average humidity of 50% RH, the air thus binds 8.6g of water per 1m³ of air. If the air is sucked into the tank, the moisture will remain there. If the hydraulic tank cools down to the ambient temperature at the end of work (critical from below 9.2°C), the humidity in the tank will condense. This means that the risk of condensation water damage in a snow groomer is very high.

Adsorber on snow groomer

In order to permanently protect the snow groomer from water, two snow groomers were equipped with adsorbers as part of a test phase lasting 15 months. The aeration dryers separate dirt particles from a size of 3µm and enable a complete drying of the air sucked into the tank.

In relation to the tank size, two original GIEBEL Adsorbers® of the VENT PA series were installed. The air drawn in was thus dehumidified to an initial 2%rh (average 10%rh). Condensation is only possible when the adsorber is used when the temperature falls below -12.5°C. This effectively protects the hydraulic system from water ingress from the air, regardless of the insulation or temperature control of the hydraulic tank.

Added value for snow groomer (oil condition)

In order to permanently protect the snow groomer from water, two snow groomers were equipped with adsorbers as part of a test phase lasting several years. The aeration dryers separate dirt particles from a size of 3µm and enable a complete drying of the air sucked into the tank.

In relation to the tank size, two original GIEBEL Adsorbers® of the VENT PA series were installed. The air drawn in was thus dehumidified to an initial 2%rh (average 10%rh). Condensation is only possible when the adsorber is used when the temperature falls below -12.5°C. This effectively protects the hydraulic system from water ingress from the air, regardless of the insulation or temperature control of the hydraulic tank.

The use of adsorbers on the Leitwolf and Husky snow groomers from the manufacturer Prinoth AG, has demonstrated a clear improvement in oil quality. Despite extreme conditions in terms of weather and temperature and the use of synthetic esters, the water content in the oil fell continuously over the entire test period of 12 and 15 months respectively. With this measure, a guaranteed maintenance interval for the entire machine, including hydraulic oil, can be maintained. Furthermore, unscheduled downtimes due to frozen water in the hydraulic system as well as the attachments are excluded. This increases the quality of the snow groomer and of the manufacturer Prinoth.

Leitwolf hydraulic tank 140 ltr.Husky hydraulic tank 60 ltr.
Date / PeriodActivityWater contentPurity classWater contentPurity class
07.11.2017Adsorber mounted
08.01.2018
(after 2 months)
Oil check490 ppm21/16/11634 ppm23/16/12
08.02.2018
(after 3 months)
Oil check498 ppm21/17/12631 ppm23/16/10
13.03.2018
(after 4 months)
Oil check474 ppm18/15/12620 ppm23/16/11
22.05.2018
(after 5.5 months)
Oil check482 ppm21/18/14598 ppm23/20/12
09.11.2018
(after 12 months)
Oil check337 ppm22/19/13480 ppm22/18/12
22.11.2018Oil change
06.02.2019
(after 15 months)
Oil check290 ppm21/19/13411 ppm23/18/13