The portable flush unit for Water Glycol is similar to the flush unit for mineral oil, but great care have to be taken on pump and filter selection. The unit is used for cleaning hydraulic tubing.
During field run installation it is very likely that dirt has entered the tubing. When the system is taken in operation without cleanup, problems will occur within a very short time. Therefor it is highly recommended to flush the hydraulic lines before commissioning and start-up.
The flush unit, which is very straight forward, contains a hydraulic reservoir, motor/pump, high pressure filter, several isolation valves and a flow meter. The purpose of the unit is to flush hydraulic oil at a high flow rate through the field run. This flow rate must be high enough to generate a turbulent flow, which can be calculated. In order to generate a turbulent flow the pump must be capable to generate a flow that is high enough, but that will also mean that pressure will be built up due to restriction in the tubing.
A positive side effect is that the oil temperature will increase up to 80°C or even higher (be aware, if the temperature of the oil is to high it will degrade the oil). The oil will be recirculated for a predefined period of time and samples will be taken during this stage to check cleanliness of the oil. Once the preferred cleanliness level has been reached a final sample will be collected in a clean for laboratory examination.