Abstract
There are some hydraulic actuators, which operates periodically. This led to a pulsating pressure in a hydraulic line. When a hydraulic actuator is placed at the tip of the crane, the hydraulic line consists of hoses because there are moving joints. The pulsating pressure decreases the reliability of the hydraulic hoses and fittings.
It is possible to reduce the pressure oscillation by help of different dampers e.g. an accumulator or a T-pipe. This paper studies the properties of the T-pipe when the operating frequency of the actuator was quite low. The result was that the T-pipe works well even at the frequency 33Hz.
The maximum working pressure of the hose is higher if the nominal size of the hose is smaller. When several small hoses are installed parallel those can be use even high oil flows. This way can be integrated the high working pressure and high oil flow. One benefit is that the hydraulic line, which is realised by several parallel installed small hoses, is more flexible than one big hose. These kinds of parallel hose systems were studied by calculating the maximum power level of different hose concepts with special interesting of price. Results show that two or several hose concept is cheapest at the power level over 100kW.
