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 fluid power system (without using […]
Read More…Hydraulic Systems Components
Virtually, all-hydraulic circuits are essentially the same regardless of the application. There are six basic components required for setting up a hydraulic system: 1. A reservoir to hold the liquid (usually hydraulic oil) 2. A pump to force the liquid through the system 3. An electric motor or other power source to drive the pump […]
Read More…Bendix Hydro Boost Brake System
This system was developed by Bendix Corporation as a solution to the typically crowded engine compartments consisting of larger vacuum units. Figure 9.3 contains a schematic of this system. The basic system consists of an open center spool valve and a hydraulic cylinder assembled in a single unit. The power steering pump supplies the operating […]
Read More…Hydraulic Power Steering
Power steering is another automotive application developed by Bendix Corporation. This is used in conjunction with a conventional type steering gear. The hydraulic power cylinder is mounted at any convenient place where it can be connected to act directly on the steering tie rod or equivalent linkage member (Figure 9.4). Power for steering is applied […]
Read More…Cooling Hydraulic Oil
Two types of heat exchanger are used to cool hydraulic oil: (1) shell-and-tube and (2) finned tube. The shell-and-tube (Fig. 8.1) has a series of tubes inside a closed cylinder. The oil flows through the small tubes, and the fluid receiving the heat (typically water) flows around the small tubes. Routing of the oil can […]
Read More…Hydraulic Contamination Control
There are three types of failure in a fluid power system. 1. Degradation. The performance of the component degrades over time as surfaces wear, clearances increase, and leakage increases. 2. Intermittent. Valves stick and then break loose such that operation is intermittent. 3. Catastrophic. Catastrophic failure occurs when a major component breaks apart. Often, debris […]
Read More…Hydraulic Contamination Sources
There are four sources of contamination in hydraulic fluid. 1. Built-in contamination. This is contaminate that was left in the system when it was assembled. It can range from a piece of teflon tape to a piece of welding slag. 2. Contaminated new oil. Contaminate is introduced during the manufacture and subsequent handling of oil. […]
Read More…Hydraulic Temperature Switch
A temperature switch is an instrument that automatically senses a change in temperature and opens or closes an electrical switching element when a predetermined temperature level is reached. Figure 6.47 is an illustration of a common type of temperature switch which has an accuracy of ±1 F maximum. This temperature switch is provided with an […]
Read More…Hydraulic Flowmeters
Flowmeters are used to measure flow in a hydraulic circuit. As shown in Figure 6.49, flowmeters mainly comprise of a metering cone and a magnetic piston along with a spring, for holding the magnetic piston in the no-flow position. Flow meters are normally not bi-directional in nature. They in fact act as check valves and […]
Read More…Hydraulic Manifolds
Leaky fittings are a cause for concern in hydraulic circuits especially with increase in the number of connections. This is where manifolds play a very important role. Their incorporation in a hydraulic circuit helps drastically reduce the number of external connections required. Figure 6.50 shows a simple manifold commonly employed in hydraulic systems. In the […]
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