9.1 Objectives

After reading this chapter the student will be able to:

• Understand the arrangement of various components in a hydraulic system

• Understand the subject of hydraulics as applied to the following:

  • Hydraulic-powered and controlled sky tram

  • Bendix hydro boost brake system

  • Power steering

  • Welding

  • Bridge maintenance.

9.2 Introduction

There are essentially three ways of transmitting power:

1. Electrical

2. Mechanical

3. Fluid power.

Most applications actually use a combination of all these three means, to obtain an efficient overall system. In order to exactly determine which of the above methods is best suited to a particular application, it is important to know the salient features of each method. For example, hydraulic systems can transmit power more economically than mechanical systems, over a larger distance. As in the case with mechanical systems, hydraulic systems are not hindered by the geometry of components in the system.

Industry today is becoming increasingly dependent on automation, in order to increase productivity. Hydraulic or fluid power can be considered to be the muscle of automation and is therefore being widely used in various applications. In the discussion to follow, we shall discuss the relative advantages of hydraulic systems and their various applications.

9.3 Advantages of hydraulic systems

A hydraulic system has four major advantages, which makes it quite efficient in transmitting power.

1. Ease and accuracy of control: By the use of simple levers and push buttons, the operator of a hydraulic system can easily start, stop, speed up and slow down.

2. Multiplication of force: A...