Research on Deformation of Hydraulic Cylinders Made of Plastics

The article presents an author’s approach to the study of the behavior of plastic hydraulic cylinder structures under load. Plastics as design materials, due to their different properties, behave differently from metals. So far, there is little information about hydraulic cylinders made of plastics. They are a technical novelty, and there are no established standards or research methods for them. The tests were carried out on the example of two models of different internal diameter, the smaller one being Ø 30 mm and the larger one Ø 50 mm. Information was gathered by FEM simulation tests and tests of real models on a special test stand. The simulation section presents geometric models, discrete models and assumed boundary conditions, as well as the results of the performed simulations. For tests of real models, a description of the stand with the measuring equipment used is presented, e.g., laser displacement sensors, as well as the method of conducting the tests and the results. Then, the results are analyzed and compared. Deformations of the examined structures are discussed, e.g., tube swelling or deflection, which seem to be characteristic for plastic cylinders. Finally, the possibility of using selected plastics for the design material of hydraulic cylinders and the suitability of the research method used are assessed.