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One of the most commonly used tests to evaluate the antiwear properties of a hydraulic fluid is ASTM D 2882 which is based on a Vicker's V-104 vane pump. Although this is a commonly used test, the results are subject to numerous potential problems in both testing procedure and pump hardware. In this paper, the particular focus will be placed on potential problems that may be encountered with testing of water-glycol hydraulic fluids which may lead to erroneous and non-reproducible results.

The ASTM test method D-2882 (Standard Test Method for Indicating the Wear Characteristics of Petroleum and Non-Petroleum Hydraulic Fluids in a Constant Volume Vane Pump) is widely used to evaluate hydraulic fluids. Performing this method can be difficult due to problems with the pump hardware and the written procedure. This paper discusses the problems and suggests possible remedies.

There is increasing interest in the development of bench tests to characterize the performance of hydraulic fluids in order to minimize the cost of testing and the volumes of fluid currently required for pump testing. One method which permits comprehensive characterization of the boundary, mixed EHD and EHD wear regimes encountered in pump lubrication is to develop a performance map. This paper discusses the use of this testing method to characterize the performance of two experimental hydraulic fluid formulations.

Cavitation is the dynamic process of gas cavity growth and collapse in a liquid. These cavities are due to the presence of dissolved gases or volatile liquids and they are formed at the point where the pressure is less than the saturation pressure of the gas (gaseous cavitation) or vapor pressure (vaporous cavitation). In this paper, various hydraulic system design factors and fluid properties affecting the cavitation process, and bubble collapse mechanisms will be discussed. In-situ generation of cavitation, examination of the cavitation process in model hydraulic systems, material effects and test methods will be reviewed.

For many years the ASTM D2882 test method, using the V-104C Vane pump, served the industry well to evaluate the lubricating properties of hydraulic fluids at low pressures (< 2000 psi). However, at higher pressures in different types of pumps (i.e. piston pumps), this method may not be reliable enough to predict satisfactory lubrication performance in commercial applications. In this paper the V-104C pump will be evaluated in terms of vane contact force and film thickness parameters to assertain the possibility of using a modified bench test to better predict hydraulic fluid performance at higher pressures.