WIS297 HYDRAULICS 02/26/1990 08:39 AM D1 294 Lines Agriculture Mechanization/Engineering and Technical Support Services Hydraulics (5-10 days) This unit deals with agricultural hydraulics technology. Topics include career opportunities, pump types and applications, reservoir needs, directional valve selection, fluid lines, safety valves, hydraulic safety switches, and hydraulic notations. Objectives To acquaint students with employment information and career opportunities in the hydraulics industry To develop student understanding in basic hydraulic principles To introduce students to components of hydraulic systems and equipment To give students the opportunities to review the operating principles of major hydraulic system components To give students the opportunities to learn maintenance and troubleshooting procedures for hydraulic systems Competencies At the conclusion of this unit, students will be able to explain current employment information such as job descriptions, job availability, personal and educational requirements, working conditions, opportunity for advancement, and other factors relative to potential employment in agricultural hydraulics and relate it to their personal needs and aspirations; explain the principles involved in hydrodynamics and hydrostatics; demonstrate and explain the relationship among pressure, velocity, flow, and power in a hydraulic system; identify the basic components and indicate the primary function of a simple hydraulic circuit; identify and discuss the characteristics and usage of hydraulic hose, tubing, and piping; identify each of the three types of fixed displacement pumps and explain the characteristics of each; sketch and explain the operational principles of a variable displacement-unbalanced vane pump, a variable displacement piston-type pump, and an internal and external gear-type pump; identify and discuss the purpose of pressure, directional, and control valves; trace the flow path of fluid through a direct acting relief valve, a pilot operated relief valve, a pressure sequence valve, and an unloading valve; explain the functions and properties of hydraulic fluids; discuss and identify fluid contaminants and the methods of removal; and describe and apply procedures of maintenance as it relates to the use of fluid lines, couplings, and seals. Subject Matter (Basic skills integration areas are shown in brackets following title.) Careers - Current and future employment needs - Job descriptions - Training requirements - Working conditions - Opportunities for advancement - Other factors Hydraulic principles [Mathematics, Science] - Relationship of pressure and flow - Transfer of energy - Methods of measuring pressure and vacuum - Determining the force, power, and horsepower - Parallel and series circuits Components of a hydraulic circuit [Science] - Functions of the basic components - Location of each component in a circuit Principles of pump operation [Mathematics, Science] - Types of pumps in common use - Pump classification - Pressure, flow, and displacement rating - Determine volumetric efficiency of pumps - Advantages and disadvantages of commonly used pumps Principles of valve operation [Science] - Pressure, directional, and flow control valves - Operating principles of commonly used valves Actuator operation - Major types of cylinders - Advantages and disadvantages of hydraulic motors - Function of accumulators Fluids, filters, and strainers - Hydraulic fluid recommendations - Filter and strainer requirements Fluid lines, couplings, and seals - Sizing tubing and couplings to a hydraulic system - Hose and tubing or pipe - Maintenance recommendations Troubleshooting - Efficiency factors - Efficiency checking process in the hydraulic circuit Universal symbols [Science] Motivational Activities Take field trips to hydraulic operations. Assemble different hydraulic pumps. View films, filmstrips, and slides on topics related to this unit. Invite an implement dealer or mechanic to give a class presentation. Post bulletin board displays on hydraulics-related topics. Learning Activities Participate in a Supervised Agricultural Experience program. Collect samples of basic hydraulic components. Construct a simulated heat exchanger and demonstrate its operation. Disassemble a cylinder and check override and cushioning devices. Determine the cost of replacing a pump on an agricultural tractor. Sketch a simple circuit and trace fluid flow in all control valve positions. Set up a hydraulic circuit on the test benches and determine its pressure, flow, and horsepower. Use a hydraulic tester to determine the efficiency of a unit's hydraulic system. Instructional Materials Textbooks and References: Basic Hydraulics by J.R. Daines. St. Paul, MN: Technical Systems, 1970. Fluid Power. Millington, TN: Navy Training Publications Center, 1966. Fundamentals of Service - Hydraulics. Moline, IL: John Deere Company, 1979. Implement and Tractor: Reflections on 100 Years of Farm Equipment by Robert K. Mills. Kansas City, MO: Intertec Publishing, 1986. Mobile Hydraulic Testing by Ronald E. Glenn and James E. Blinn. Chicago: American Technical Society, 1970. Bulletins and Pamphlets The following are available from the American Association for Vocational Instructional Services. Hydraulics for Tractors and Other Mobile Equipment Volume II: Inspecting and Testing. 121. 1974. Safe Tractor Operation and Daily Care. 103. 1981. The following is available from the American Oil Company. Hydraulic Power Transmission The following is available from the National Fluid Power Association. A Course Outline for an Introduction to Fluid Power The following is available from the Owatonna Tool Company. Basic Hydraulic Principles and Trouble Shooting Suggestions The following are available from the Sperry Rand Corporation. Mobile Hydraulics Manual - Basal Practical Hydraulics The following is available from Technical Publications, Inc. I & T Shop Service The following is available from the United States Government Printing Office. Vocational Education and Occupation Handbook. FS 5.280:80061. Periodicals Hydraulics and Pneumatics Implement and Tractor Computer Software The following are available from Hobar Publications. Hydraulics and Related Review. Apple, IBM, TRS, Macintosh. Introduction to Machinery Management. Apple. Tractor Preventative Maintenance Review. Apple, IBM, TRS, Macintosh. The following is available from Mid States Agri-Technology Associates, Ltd. Micro-Tutor: Tractors. Apple, IBM. On-line Computer Networks The following are available from Ag Ed Network, AgriData Resources, Inc. Hydraulic Cleaning. CSU209. Hydraulic Fluids. CSU208. Hydraulic Hoses. CSU212. Hydraulic Leaks. CSU210. Hydraulic Repair. CSU213. Hydraulic Replacement. CSU211. Hydraulic Safety. CSU207. Hydraulic Systems. CSU206. Laboratory Resources The following is available from the John Deere Company. Hydraulics Workbook. 1979. Films, Videotapes, and Slides The following is available from the Jam Handy Organization. Basic Principles of Hydraulics. (16mm film.) The following is available from the John Deere Company. Hydraulics. FOS-10035 (209 color slides). 1979. The following is available from Sperry Rand Corporation. Controlled Power. (16mm film.) The following are available from United World Films, Inc. Application of Pascal's Law Part I. (16mm film.) Application of Pascal's Law Part II. (16mm film.) The following are available from the Visual Education, Inc. Applied Hydraulics. (Slides.) Basic Hydraulics. (Slides.) Hydraulic Cylinders. (Slides.) Hydraulic Pumps. (Filmstrip.) Hydraulic System for Grain Harvesting. (Slides.) Hydraulic Valves. (Filmstrip.) Equipment and Facilities Hydraulic test bench Example pumps (rejects/nonrepairables from manufacturers, local dealers, or salvage yards)