Category Archives for Hydraulic Control System

Flow Trough Orifice

Orifices are a basic means for the control of fluid power. Flow characteristics of orifices plays a major role in the design of many hydraulic control devices. An orifice is a sudden restriction of short length (ideally zero length for … Continue reading

18. June 2018 by Dan
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Disadvantages of Hydraulic Control

Although hydraulic controls ofl’er many distinct advantages, several disadvantages tend to limit their use. Major disadvantages are thie following: 1. Hydraulic power is not so readily available as that of electrical powe:r This is not a serious threat to mobile … Continue reading

18. June 2018 by Dan
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Advantages of Hydraulic Control

There are many unique features of hydraulic control compared to other types of control. These are fundamental and account for the wide use of hydraulic control. Some of the advantages are the following: 1. Heat generated by internal losses is … Continue reading

18. June 2018 by Dan
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Hydraulic Compensated Four-way Control Valve Characteristic

There are many ways of compensating for the reaction forces in spool type valves. In general most of these methods do not actually change the reaction force characteristics at each orifice. The general trend is to try either to nullify … Continue reading

27. June 2013 by Jack
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Hydraulic Uncompensated Four-way Control Valve Characteristic

Figure 1.11 illustrates the valve reaction forces for an uncompensated four-way valve. It can be noticed that the forces become very large for the higher flows and at large valve openings. AB the valve spool is moved to even larger … Continue reading

27. June 2013 by Jack
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Hydraulic Four-way Control Valve Leakage Characteristic

In addition to the flow which the valve supplies to the piston, there is also a small amount of leakage flow within the valve itself. Since there must be some diametral clearance between the valve spool and its sleeve, there … Continue reading

26. June 2013 by Jack
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Hydraulic Four-way Control Valve Characteristic

The four-way valve is so-named because of the required number of hydraulic lines to the valve as shown by Fig. above. The four-way valve requires a minimum of four lines, a fluid supply, two control lines to an actuator, and … Continue reading

26. June 2013 by Jack
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Hydraulic Valve Characteristic

Proportional valves provide control of fluid power by a combination of variable-area orifices or in some cases by a combination of both fixed and variable orifices. By varying the area of the orifices, the desired relationship of flow and pressure … Continue reading

26. June 2013 by Jack
Categories: Hydraulic Control System | Tags: | Leave a comment