Engineering and Design Lubricants and Hydraulic Fluids pdf

CECW-ET Engineer Manual 1110-2-1424 Department of the Army U.S. Army Corps of Engineers Washington, DC 20314-1000 EM 1110-2-1424 28 February 1999 Engineering and Design LUBRICANTS AND HYDRAULIC FLUIDS Distribution Restriction Statement Approved for public release; distribution is unlimited. [...]... between cSt and SUS viscosities at standard temperatures can also be obtained from ASTM D 2161 3-7 EM 1110-2-1424 28 Feb 99 Chapter 4 Hydraulic Fluids 4-1 Purpose of Hydraulic Fluids a Power transmission The primary purpose of any hydraulic fluid is to transmit power mechanically throughout a hydraulic power system To ensure stable operation of components, such as servos, the fluid must flow easily and must... mineral oils and are compatible with them Applications include engine and turbine oils, hydraulic fluids, gear and bearing oils, and compressor oils (b) Organic esters Diabasic acid and polyol esters are the most common types The properties of these oils are easily enhanced through additives Applications include crankcase oils and compressor lubricants (c) Phosphate esters These oils are suited for fire-resistance... corrosion protection; thermal and oxidation stability; antiwear properties; compatibility with seals, paints, and other oils; and compliance with testing and standard requirements Unlike Plant Engineering magazine’s “Chart of Interchangeable Lubricants, ” it is important to note that synthetic oils are as different from each other as they are from mineral oils Their performance and applicability to any specific... fire-resistance and enhances the fluid cooling capability Emulsifiers are added to improve stability Additives are included to minimize rust and to improve lubricity as necessary These fluids are compatible with most seals and metals common to hydraulic fluid applications The operating temperature of water-in-oil fluids must be kept low to prevent evaporation and oxidation The proportion of oil and water... 204 EC (400 EF) and auto-ignition temperatures above 483 EC (900 EF), making these fluids less likely to ignite and sustain burning Halogenated hydrocarbon fluids are inert, odorless, nonflammable, noncorrosive, and have low toxicity Seal compatibility is very important when using synthetic fluids Most commonly used seals such as Nitrile (Buna) and Neoprene are not compatible with these fluids c Environmentally... Environmentally acceptable hydraulic fluids The requirements for biodegradable fluids are discussed in Chapter 8 4-5 EM 1110-2-1424 28 Feb 99 4-6 Cleanliness Requirements Due to the very small clearances and critical nature of hydraulic systems, proper maintenance and cleanliness of these systems is extremely important Hydraulic system cleanliness codes, oil purification, and filtration are discussed... applications hydraulic fluids must provide the seal between the lowpressure and high-pressure side of valve ports The amount of leakage will depend on the closeness or the tolerances between adjacent surfaces and the fluid viscosity d Cooling The circulating hydraulic fluid must be capable of removing heat generated throughout the system 4-2 Physical Characteristics The physical characteristics of hydraulic fluids. .. fracture, corrosive fatigue, and stress corrosion c Stability The stability of a hydraulic fluid is the most important property affecting service life The properties of a hydraulic fluid can be expected to change with time Factors that influence the changes include: mechanical stress and cavitation, which can break down the viscosity improvers and cause reduced viscosity; and oxidation and hydrolysis which... for decreasing the stability of hydraulic fluids Once the reactions begin, a catalytic effect takes place The chemical reactions result in formation of acids that can increase the fluid viscosity and can cause corrosion Polymerization and condensation produce insoluble gum, sludge, and varnish that cause sluggish operation, increase wear, reduce clearances, and plug lines and valves The most significant... of dissolved air from the fluid d Demulsibility or water separation Water that enters a hydraulic system can emulsify and promote the collection of dust, grit, and dirt, and this can adversely affect the operation of valves, servos, and pumps, increase wear and corrosion, promote fluid oxidation, deplete additives, and plug filters Highly refined mineral oils permit water to separate or demulsify readily . February 1999 Engineering and Design LUBRICANTS AND HYDRAULIC FLUIDS 1. Purpose. This manual provides guidance on lubricants and hydraulic fluids to engineering, operations, maintenance, and construction. of Engineers Washington, DC 20314-1000 EM 1110-2-1424 28 February 1999 Engineering and Design LUBRICANTS AND HYDRAULIC FLUIDS Distribution Restriction Statement Approved for public release; distribution. Engineers CECW-ET Washington, DC 20314-1000 Manual No. 1110-2-1424 28 February 1999 Engineering and Design LUBRICANTS AND HYDRAULIC FLUIDS Table of Contents Subject Paragraph Page Chapter 1 Introduction Purpose