| Abstract [eng] |
Hydraulic loader cranes which are used in Lithuania has to comply to LST EN 12999:2011+A1:2012 standard, which covers main requirements for construction and testing of cranes. According to above mentioned standard is foreseen 1,4 vehicle’s stability factor, which is calculated with corresponding software before manufacture of complete vehicle and only on fully assembled vehicle structural strength, safety and stability practical tests are carried out. The tests consist of static and dynamic tests, during which the stability of complete vehicle is tested and functionality of hydraulic and elector-hydraulic valves is checked. Tested objects are vehicle’s with hydraulic loader crane mounted on rear part without additional stabilizers in front and software calculated stability factor. Stability factors according to the software in front and rear part of vehicle is more than minimum parameter that is required and on the side parts was too low. Stability factor on the right side is 1,35 and 1,38 on the left that do not corresponds to the above mentioned standard. In these sections lifting capacity of crane has to be reduced to 96% on the right side and to 98% on the left side. During the practical dynamic and static testing of the crane lifting capacity diagram was programmed. Lifting capacity was reduced to 95% on the right side and to 96% on the left side of vehicle. The difference between these two diagrams is up to 2 %, so on purpose to program exact lifting diagrams in numerical method for the further on vehicles it has to be accomplished more comparative studies. These studies would minimize the mismatch between the diagrams. |
