Mumbai University > Electronics and telecommunication > Sem 7 > Applied Hydraulics

Marks: 08

Years: MAY 2016

The device, which is used to increase the intensity of pressure of water by means of hydraulic energy available from a large amount of water at a low pressure is called the hydraulic intensifier. Such a device is needed when the hydraulic machines such as hydraulic press requires water at very high pressure which cannot be obtained from the main supply directly.

A hydraulic intensifier consists of fixed ram through which the water, under a high pressure, flows to the machines. A hollow inverted sliding cylinder is surrounded by another fixed inverted cylinder which contains water from the main supply at a low pressure as shown in fig.

A large quantity of water at low pressure from supply enters the inverted fixed cylinders. The weight of this water pressure the sliding cylinder in the downward direction. The water in the sliding cylinder gets compressed due to the downward movement of the sliding cylinder and its pressure is thus increased. The high pressure water is forced out of the sliding cylinder through the fixed ram to the machine as shown

Let

p = Intensity of pressure of water from supply to the fixed cylinder (low pressure water)

A = External area of the sliding cylinder

a = Area of the end of the fixed ram

p* = Intensity of the pressure of water in the sliding cylinder.

The force exerted by low pressure water on the sliding cylinder in the downward direction = $p\times A$

The force exerted by the high pressure water on the sliding cylinder in the upward direction = $p^*\times a$

Equating the upward and downward forces

$p\times A = p^* \times a \\ p^*= \dfrac {p\times A}a$