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Preface
Hydraulic Systems for Mobile Equipment is intended to educate students in heavy equipment
and heavy truck programs. Although the text has a primary emphasis on agricultural and construc-
tion machinery, it can empower students working in any related fi eld of hydraulics. To this end, it
teaches and is correlated to the competencies of both AED Hydraulics/Hydrostatics Standards and the
Hydraulics section of the NATEF Medium/Heavy Duty Trucks Task List. The scope and approach of the
book make it appropriate for all students, whether they are pursuing a certifi cate, associate’s degree,
bachelor’s degree, or a master’s degree.
This textbook includes traditional hydraulic content such as fl uid power principles, pumps, motors,
safety, valves, fi ltration, accumulators, plumbing, reservoirs, coolers, and fl uids. In addition, the book
is especially unique in providing the fundamental explanation of the most common types of mobile
hydraulic control systems, specifi cally open center, pressure compensating, pre-spool load sensing
pressure compensating, post-spool compensation (fl ow sharing), negative fl ow control, and positive
fl ow control.
The text provides fundamental instruction on hydrostatic transmissions with the goal providing
students true comprehension of the systems. This will free the students from relying solely on discrete
(or limited) troubleshooting charts. Students will also gain instruction in hydraulic diagnostic princi-
ples such as how to tap into the system, what tools are available, how to properly use those tools, how
to perform the tests safely, and what to look for when performing the tests.
Hydraulic Systems for Mobile Equipment provides students the necessary foundational building
blocks, equipping them for a bright future in hydraulic technology. The book includes hundreds of
images comprised of multicolor line art, cross-sectional drawings, photographs, and 3D renderings.
The book includes practice questions, cases studies, and helpful techniques for diagnosing hydraulic
systems.
As society transitions from printed textbooks to digital learning tools, it is important to have the
content you need in the format you need it in. The Hydraulic Systems for Mobile Equipment text-
book is available in both print and digital formats, and is supported with professionally developed,
user-friendly online resources. These resources include electronic study tools and interactive activities
designed to prepare you for success in your studies and career.
Congratulations on your study of hydraulics technology, and I encourage you to take advantage
of all the resources available as part of the Hydraulic Systems for Mobile Equipment learning
solution.
Tim Dell