This article deals with the comparison of the energy consumption of the hydraulic control system of the working mechanisms of the telescopic excavator UDS 114. There is described the hydraulic system of the excavator. In order to compare the individual losses in the hydraulic circuits for controlling the working mechanisms, the hydraulic oil flow rates through the OTC H50 meter were measured. Firstly, f (…)
Development and research for an Open Center System (OC-System), which is typically used for excavators, has been conducted from the perspective of hydraulic efficiency. However, total system efficiency including the internal combustion engine (ICE) has not been considered thoroughly. On the other hand, a Constant Pressure System (CP-System) enabling the engine to be driven optimally is developed but is (…)
The consideration of the drivetrains behavior under real operating conditions is becoming increasingly important. While in the past decades it was good enough to have a rough knowledge about the operation conditions in field, a more accurate and detailed picture of the duty cycles is required today. Caused by specific and complex operation conditions the load deviation between different applications is (…)
The paper is focused on the description and creating of the simulation model of the power assisted steering and testing of the functionality and efficiency on the laboratory test rig. The mathematical model is describing the structure of the system and is created from the mathematical models of the subsystems, which compute the dynamic behaviour of the steering wheel, pinion, rotating control valve and (…)
The paper deals with a manufacturing technology of hot-rolled sections. A calibration system proposal of the solved section is described and its accuracy is subsequently verified by numerical simulation using Simufact Forming software. In this case, S355J2 steel is used as a material for a trial production of the rolled profile. Finally, according to the verified design, the trial rolling of the section (…)
Engineering design is the preliminary and significant technique for manufacturing the machine parts. Conventional design methodology is the process by which desired models are transformed into real parts. Using reverse engineering concept, the real parts are transformed into models. This article deals with developing a methodology for reverse engineering of machine parts with parametric surfaces. Real p (…)
For measuring was used the combine harvester John Deere S685i with track units. For reading of tension force there was used specially developed measurement tool - a pull dynamometer. It is constructed as a towing drawbar which was connected between rear hitch of combine harvester and three-point hitch of pulling tractor. It means that measuring set moved in reverse mode. Measuring was running on the sam (…)
The paper relates to the fluid force acting on the journal of the slide bearings and its movement at stable lubrication. These forces can be calculated using the Reynolds equation. The analysis is based on the solution of the simplified equation and the experimental verification with the use of the test rig. The assumptions are verified by the numerical solution of the Reynolds equation by the FVM method.
In modern industrial practice, innovative solutions for the improvement of processes or whole production or logistical systems are continually proposed. There are many options offered, but the problem arises in verifying the correctness of decisions and their impact on the functioning of logistic processes and the entire production system after the implementation of the changes. Forecasting or experimen (…)
In the article the construction of an experimental device for measuring the characteristics of small rotary air motors is described. Further a measurement methodology and measured data processing is explained. At the end of the article using of the measured characteristics for mathematical modelling is presented.
The performance of a mechanical filter is an implicit function of many variables pertinent to fluid condition, flow variables, filter element condition and operational parameters. This paper presents the details and results of a parametric study that examined the effect of oil temperature, contamination level and flow rate on the performance of a hydraulic filter through laboratory experiments. A 5 µm r (…)
Two methods are generally possible to design and optimize hydraulic components and devices. The classic method is the experimental method. In the hydraulic laboratories, various models of components and devices are examined to understand their basic properties, to verify proposed assumptions, or to alter derived theoretical equations to equations that approximate reality, etc. In some cases, which are (…)
Residual stress occurs in many machined components and parts and they cause the corrosion or destruction of components. The paper deals with evaluating residual stresses during an irregular interrupted cut with the use a ceramic cutting tool. Tests were performed on the conventional lathe with using a simulator of interrupted cut called “slats test”. The regular or irregular interrupted cutting process (…)
The paper deals with the determination of the precise calculation of carbon diffusion and carbon prediction in the production of gear wheels cementation from steel by Czech standard (steel CSN 14220, or ASTMA 506). In the research part of the paper, considerable attention is paid to the determination of the necessary data for calculating the cementation, especially the mass- the carbon-binding coefficie (…)
The paper deals with the analysis of the finishing of very precise holes by the applied MT3 reaming head from FINAL Tools Inc. In the case of a narrow range of customers with particularly high demands on the quality of the holes is currently appearing effort to elaborate a detailed evaluation of surface quality through evaluation of surface integrity. These facts led to the design of an experimental p (…)