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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.

Like all industries, the fluid power industry is under increasing pressure to identify and use hydraulic fluids that offer higher performance, improved fire safety, and exhibit improved environmental and toxicological behavior. Recently a novel hydrolube composition has been developed that is capable of being used in hydraulic pumps at pressures of 34.4 MPa (5000 psi) and greater*. In addition to being a Group 1 Fire Resistant Hydraulic Fluid according to the new Factory Mutual Research Corporation's testing methodology, this high-performance hydrolube also exhibits excellent biodegradability and toxicology properties. The objective of this paper is to discuss pump performance, fire resistance, and environmental and toxicology properties of this fluid..

The importance of minimizing air entrainment and enhancing air release in hydraulic fluids has been recognized for over 40 years. These properties are dependent on the composition of hydraulic fluids, especially on the presence of contaminants which inhibit air release and additives which promote it. One objective of this paper is to present an overview of this critically important technology as it has unfolded over the last 40 years. The second objective of this paper is to integrate into this summary recent research results on the impact of additives on air release properties.

Because of on-board fire problems during World War II, the us Navy initiated a program to develop hydraulic fluids that were more fire-resistant than the mineral oils that were in use at that time. Water-glycol hydraulic fluids were subsequently developed and first commercialized in 1947 which offered vastly improved fire resistance relative to mineral oils. Since 1947, in addition to formulation changes, there is significantly greater understanding of the impact of these changes on pump wear performance. This paper will present a selected overview of water-glycol formulation chemistry, some of the fluid formulation issues that have been encountered and the evolutionary improvement of hydraulic pump wear performance.

Hydraulic fluid performance, including water-glycols (W/G), is dependent on the chemical composition of the fluid and cleanliness. An overview of W/G fluid chemistry on pump wear is provided here. Also provided, is a brief overview of the impact of fluid cleanliness on the potential wear properties of various components. Finally, an overview of recommended analytical procedures to assure adequate long-term fluid hydraulic and lubrication performance is provided. If these procedures are followed, substantial improvements in hydraulic pump longevity and performance will be realized.

Automotive water pump seals which have failed prematurely during in-service use have been characterized using a variety of analytical methods. Nearly one hundred failed seals collected over the past several years from local automotive dealerships, major automotive manufacturers, coolant related fleet tests, and pump seal manufacturers have been examined as part of this study. This has enabled us to determine the chemical composition and morphology of surface deposits on failed seals and classify their failure mode. The main failure mode found for domestic in-service automobiles is filming, a term used to describe a failure type in which deposits form between the sealing surfaces resulting in a leak path. This paper reports on the composition, morphology and possible causes of in-service filming failures. In addition, the results of this study will be contrasted with those reported in other studies which found film transfer as the main type of failure.

Reaction Injection Molding is rapidly becoming accepted as a viable industrial process for preparing large intricate parts using reactive urethane intermediates. High modulus polymers are among the newest systems capable of being prepared using the RIM process. Proper balance of the many features of urethane chemistry and technology allows preparation of high modulus material with excellent properties, including impact resistance. Fillers can be added to these high modulus polymers to increase their moduli even further. Studies have shown that milled fiberglass added to certain polymers can result in a composite with a flexural modulus in excess of 320M psi (2206MPa).