Functional description
The VacuClean system removes dirt, oil aging products, gases as well as free and dissolved water from hydraulic and lubricating oils in a multi-stage process.
A gear pump delivers the medium into the system. After the pre-filter, the oil is degassed and allowed to settle in the rotor recess. Afterwards, the medium is transferred into a laminar flow via the spiral in the evacuated process chamber. The integrated fresh air transports the leaking water steam to the suction system in a directed manner. In the capacitor, the water is separated and used to lubricate the oil-free water ring vacuum pump. Excessive water is discharged via a line. The exhausted air is then discharged in an oil- and steam-free form.
After passing through the process, the dewatered oil is led through a low pressure-resistant gear pump to the main filter and pumped back into the tank. Solenoid valves in the inlet and outlet will immediately lock the system in case of fault in order to prevent leakage.
The two-stage filtration consisting of coarser pre-filtration and the downstream fine filter also allows for very good cleaning results in case of high viscosities and flows with long service life of the filter elements. In the vacuum chamber evacuated by the high-performance vacuum pump, the pressure is reduced so that free oil and oil dissolved in the water even evaporates at low temperatures. AT the some time, gases dissolved in the oil as well as other liquid contamination such as oil acids are removed.
Use
In the operational practice, more than 3/4 of all problems in fluid systems can be attributed to oil contamination. Here, the use of VacuClean allows for the reduction of operating and downtime costs considering economic observations. By means of the mobile oil cleaning device, it is possible to achieve multiplication of the hydraulic oil service lives with little expense and - by means of improvement of the oil condition - considerably reduced wear of the system components and thus lower operating costs.
Typical types of contamination in the hydraulic and lubricating oil are solid materials (particles), foreign liquids and air. Solid materials and particles may enter the system from the outside (fresh oil; breathing of the system) or by abrasion and component wear. Especially the hard particles will then again lead to an acceleration of component wear and finally to their failure.
Liquid contamination, mostly water in free or dissolved form, may have serious consequences and cannot be removed by the usual filtration of the medium. Water dissolved in oil or even free water leads to corrosion, impairment of the viscosity, deterioration of the lubrication properties and consequently to increased wear. Other problems result from chemical reactions of the fluid in the presence of water, air and metal particles resulting in oil aging and oil oxidation.
Gaseous contamination, usually air dissolving in the tank in the oil, impairs the response behavior of valves, cause foaming, energy loss and pump damage.
- Water preferably settles in fine cracks of balls and sliding surfaces where it causes corrosion.
- The oxidation (fluid aging) is greatly accelerated by the reaction with metal particles with catalytic effect
- Water increases the acid value (TAN) to four to ten times the value and in this way accelerates the fluid decomposition
- In dissolved and emulsified form, the viscosity and lubricating property of the fluid is changed. This leads to increased friction, heat development and wear.
- Due to its high dielectric constant, dissolved water attracts dust leading to fluid contamination and the formation of dust lumps which may, e.g. clog servo valves. Due to the low particle size of the individual dust particles, it is, however, very hard to remove them again by means of filtration.
- Polarizable additives are dissolved from the fluid which further deteriorates its properties
- Water promotes the sludge formation
- Water deteriorates the filtrability of the fluid
The mobile oil cleaning system which is easy to handle allows for the cyclic or permanent cleaning of a complete hydraulic circuit in the bypass. The extensive filters with high dirt holding capacity can also be operated in a cost-effective manner with low pressure differentials in case of very high filter ratings.
Thanks to the underpressure reached in the evacuated vacuum chamber, effectively dissolved and also free water is already removed at low oil temperatures and during the process, the entire hydraulic system is dried.
