In order to increase the outreach for handling the load, loading cranes use the telescopic boom system. One of the main components of the boom system is a hydraulic cylinder, which provides extraction and putting away one or more telescopes simultaneously. The cylinders inside or outside of the telescopic extension are placed sequentially. They are connected to the hydraulic system via hydraulic flexible hoses. Along with changing the outreach of the telescopic extension the distance between individual cylinders changes as well, so the flexible hoses need to be additionally guided because of constant twisting and extending. This also presents a problem in terms of endurance.
The purpose of this diploma paper is designing the electrically controlled cylinder for crane telescopic boom. It must provide a smooth oil flow for sequential connection of two or more cylinders of the telescope. The maximum pressure within the hydraulic cylinder amounts to 30 MPa and the maximum volume flow rate of oil at the cylinder inlet amounts to 40 l/min. The steering of the cylinder should be electric. The numerical calculations of the liquid flow through the cylinder must be done. The results obtained are to be analysed. Based on the calculations improvements of the hydraulic telescope prototype are to be suggested.