Effect of Temperature Variation on Oil in Oscillation of Mass/Load

In this investigation a model was made to replicate the working of a shock absorber and the liquid that is used in place of the hydraulic fluid was vegetable oil. Hydraulic fluid is composed of a mineral oil base stock [1]. The working of the model of a shock absorber was tested at different temperatures. It is studied that the relation between the temperature and the time taken by the load attached to the spring to stop oscillating and presented in graph. An optimum temperature, at which the time taken by the mass of 1.50 kilograms suspended in the vegetable oil to stop oscillating and it is the least mass used in the study. In addition to this, the freezing point of the vegetable oil will also be found. It is found in this study that the two variables that is temperature of the vegetable oil and the mass of 1.5 kilograms at rest is linear. Keywords: Temperature Variation, Oil, Oscillation, Mass, Load.

The importance of the electrical properties of hydraulic fluids

Purpose Apart from the basic material properties of liquid lubricants, such as, e.g., the viscosity and density of the hydraulic fluid, it is also important to have information regarding the electrical properties of the fluid used. The latter is closely related to the purpose, type, structure, and conditions of use of a hydraulic system, especially the powertrain design and fluid condition monitoring. The insulating capacity of the hydraulic fluid is important in cases where the electric motor of the pump is immersed in the fluid. In other cases, on the basis of changing the electrical conductive properties of the hydraulic fluid, we can refer its condition, and, on this basis, the degree of degradation. Design/methodology/approach The paper first highlights the importance of knowing the electrical properties of hydraulic fluids and then aims to compare these properties, such as the breakdown voltage of commonly used hydraulic mineral oils and newer ionic fluids suitable for use as hydraulic fluids. Findings Knowledge of this property is crucial for the design approach of modern hydraulic compact power packs. In the following, the emphasis is on the more advanced use of known electrical quantities, such as electrical conductivity and the dielectric constant of a liquid. Originality/value Based on the changes in these quantities, we have the possibility of real-time monitoring the hydraulic fluid condition, on the basis of which we judge the degree of fluid degradation and its suitability for further use.

Development of Glycerin/Chitosan-Based Fluids for Stationary and Mobile Hydraulic Drives

A hydraulic fluid based on water, glycerol and the thickener chitosan was developed in preliminary tests at Technische Universität Braunschweig. In terms of fluid properties, the fluid is comparable to those of conventional fluids. Due to the promising properties of the fluid, further development of the fluid is now being worked on. The focus is on further development for practical use in mobile hydraulic systems, e.g. in agricultural and forestry machinery. The aim here is to optimize various fluid variants for different applications and to define the possible range of uses in general. This paper presents interim results from the development of the fluids and the investigations of the fluids in a wide range of laboratory tests and endurance tests in a hydraulic test bench.

Equipment for Damping Hydraulic Shocks in Pressure Hydrotransport Facilities

Newly developed equipment for damping hydraulic shocks in pressure hydrotransport facilities is reviewed in this article. This equipment includes a discharge, safety diaphragm, as well as a flexible diaphragm, which is connected to the main pipeline at both different ends of the backpressure valve. A rupture disc is attached to it from below and load is attached from above by means of a rod, so that it can efficiently act during movement of hydraulic fluid in the central main pipeline, i.e. when the flow to be transported contains abrasive contaminant of solid material. The load represents a piston, which is rigidly connected to the flexible diaphragm and the rupture disc and creates an airproof space filled with viscous fluid. At the same time, the lower space is isolated from the main pipeline by a flexible separating element before the backpressure valve and the upper space is also isolated by a flexible separating element located after the back pressure valve.

Development of portable filtration unit with self-diagnostics for industrial use

It is well known that contamination of fluids shortens the life of hydraulic systems. Sometimes the necessary operating conditions (high pressures and high flow rates) make adequate filtration in the suction, working, or return lines through the filter difficult because it would interfere with the work process. A high cleanliness of the oil can be achieved with a so-called "bypass" filtration, which is part of the whole hydraulic device with its own circuit. Another way to ensure fluid cleanliness is to filter the hydraulic fluid with a portable filtration unit, which is the main topic of this paper. The fluid is pumped from the reservoir of the main hydraulic device, through the portable filtration unit and returned to the reservoir. In this way it is possible to clean the hydraulic oil without the need for costly and unnecessary "bypass" hydraulic components for filtration.

Flow conditions inside a small hydraulic tank at excessive flow rates

The basic purpose of a hydraulic tank is to hold a volume of fluid, transfer heat from the system, allow solid contaminants to settle and facilitate the release of air and moisture from the fluid. To perform these important tasks more efficiently, the tank must be dimensioned properly. Above all, it must have an appropriate size. If the tank is too small the flow conditions inside the tank deteriorate, resulting in inadequate conditioning of the hydraulic fluid. Based on the simulation, the paper presents the difference in the change of flow conditions in the case of adequate and insufficient tank sizes. A small industrial hydraulic tank with a capacity of 30 litres filled with hydraulic mineral oil was used as the example of the study.