Fluid Power (Part 2) – Hydraulic Power Units
A. Bhatia, B.E.
Course Outline
Fluid systems are utilized in many engineering systems like machine tools, heavy machinery, chemical processes, automotive equipment, aircraft, missiles, and space vehicles. All fluid systems involve the use of power unit comprising of pumps, valves, piping, tubing, and hoses used to convey fluid under pressure.
This 5 -hour course provides an overview of the various types of pumps, valves, tubing and flexible hoses. It also discusses several types of seals and packing used in fluid power systems. This course material is based entirely on the NAVEDTRA NONRESIDENT TRAINING COURSE 14105 titled “Fluid Power” wherein the readers will be introduced to chapters 4 thru 7.
Chapter -4: Pumps
Chapter -5: Fluid lines and fittings
Chapter -6: Valves
Chapter -7: Sealing devices and materials
This course includes a multiple-choice quiz at the end, which is designed to enhance the understanding of the course materials.
Learning
Objective
At the conclusion of this course, the student will understand:
- Classification of pumps - non-positive displacement, positive displacement, fixed displacement, variable displacement, fixed delivery, variable delivery, constant volume and others used to describe pumps;
- Construction details of rotary, gear, lobe, screw, vane and piston pumps;
- Pump Performance and selection of pumps for appropriate application;
- Different types of fluid lines including rigid piping, semi rigid tubing and flexible hoses used to carry fluids under pressure;
- Selection criteria of sizing and defining lines that include material, ID, and wall thickness;
- Methods of preparation of pipes and tubing including cutting, bending, flaring;
- How to select and identify flexible hoses, and learn how to determine the shelf life of hoses using cure date;
- Fittings and connectors used in hydraulic system piping including threaded connections, flange connectors, welded and brazed connectors;
- Application of manifolds and quick disconnect couplings;
- Classification and operation of valves used in the control of flow, pressure, and direction of fluids;
- Types of valves – ball valves, gate valves, globe valves, needle valves, check valves, shuttle valves;
- Application of pressure controllers, pressure regulators, pressure reducing valves, directional control valves, sequence valves and relief valves;
- Direction control valves – construction details- types and classification of direction control - 2-way, 3-way and 4-way valves;
- Material classification of seals based on the application; and
- Identification, characteristics (shelf life, cure date), storage and replacement of different types of seals - T seals, V rings, O rings, quad rings, U cups, and flange packing’s.
Intended
Audience
This course is applicable to mechanical engineers, process engineers, automotive engineers, machine designers, constructors, mechanics, operators and others involved in design and operation of industrial machinery.
Benefit to Attendees
Attendee of this course will get acquainted with the working of various components found in fluid power equipment and learn how to apply them to practice. The course will be extremely helpful to the amateur engineers who desire to build on their design experience and the skilled professionals who have learnt the trade informally on the job.
Course Introduction
This course introduces 4 important components of hydraulic system:
- A pump - to convert mechanical power to fluid power;
- A valve - to control the direction and amount of flow;
- Hose, tube and couplings - to conduct the fluid;
- Seals - to contain the fluid;
This course is applicable for participants who are familiar with the basic operating principles of hydraulic systems. Those new to hydraulic systems must take a fundamental course titled “Fluid Power (Part 1) – Hydraulic Principles, which is separately listed.
Course
Content
This course is in the following PDF document:
Fluid Power (Part 2) – Hydraulic Power Units
Please click on
the above underlined hypertext to view, download or print the document for your
study. Because of the large file size, we recommend that you first save the
file to your computer by right clicking the mouse and choosing "Save Target
As ...", and then open the file in Adobe Acrobat Reader. If you still experience
any difficulty in downloading or opening this file, you may need to close some
applications or reboot your computer to free up some memory.
Course Summary
Two of the most important advantages of fluid power transmission are its ability to multiply force and its ability to change direction quickly without damage to the system. The flexibility of fluid power results because the medium of transmission is a flowing fluid, which allows flexible hoses to be used. This makes it very easy to change direction and transmit the power through angles.
This course introduced 4 major components of hydraulic systems:
- Pumps - to convert mechanical power to fluid power. Various types of pumps used in hydraulic machinery include rotary, gear, lobe, screw, vane and piston pumps.
- Valves - to control the direction and amount of hydraulic fluid flow. Various types of valves used in hydraulic machinery include ball valves, gate valves, globe valves, needle valves, check valves, shuttle valves. Pressure controllers, pressure regulators, pressure reducing valves, directional control valves, sequence valves and relief valves are required for safety and reliability of hydraulic machines.
- Hose, tube and couplings - to carry fluids under pressure. Different types of fluid lines include rigid piping, semi rigid tubing and flexible hoses. The tubing must be properly connected to the hydraulic system for safety.
- Seals - to prevent leakage and to contain the fluid. Classification and selection of sealing devices is based on the application. The sealing types may include - T seals, V rings, O rings, quad rings, U cups, flange packing’s and back-up rings.
Proper selection of fluid power components ensures safety, guarantees quality and reliability.
Quiz
Once
you finish studying the
above course content,
you need to
take a quiz
to obtain the PDH credits.
DISCLAIMER: The materials
contained in the online course are not intended as a representation or warranty
on the part of PDH Center or any other person/organization named herein. The materials
are for general information only. They are not a substitute for competent professional
advice. Application of this information to a specific project should be reviewed
by a registered architect and/or professional engineer/surveyor. Anyone making
use of the information set forth herein does so at their own risk and assumes
any and all resulting liability arising therefrom.