accumulators and intensifiers

1. HYDRAULIC ACCUMULATOR
AND INTENSIFIER

2. HYDRAULIC
ACCUMULATOR

3. INTRODUCTI
ON
A Hydraulic Accumulator is energy storage device.
It is pressure storage reservoir in which a non- compressible
hydraulic fluid is held under pressure by an external source.
The external source used can be a spring, a raised
weight, or a compressed gas.
The main reasons that an accumulator is used in a hydraulic
system, is that the pump doesn’t need to be so large to cope
with extremes of demand and supply circuit can respond
quickly to any temporary demand and to smooth pulsation.

4. HISTO
RY
First Hydraulic accumulator was made by
William Armstrong in 1846 built a crane
powered by water of town mains at
Newcastle, United Kingdom.
Later 1852 ,Armstrong used Grimsby
Dock Tower for the constant pressure
for cranes, lock gates and sluices.
Grimsby Dock Tower is hydraulic
accumulator is used for the purpose of
containing a 30,000UK gallon (136 m3)
hydraulic wrought iron reservoir at a
height of 300feet (91 m) to provide
power for lock gates and cranes of
Grimsby Dock.

5. 1. Tower type accumulator
2. Raised weight accumulator
3. Compressed-gas accumulator
4. Spring accumulator
TYPES OF HYDRAULIC ACCULUMATOR

6. 1. TOWER TYPE
ACCUMULATOR
The first accumulators for Armstrong’s
hydraulic dock machinery were simple
raised water tower.
It uses hydraulic head
It delivers constant pressure to the
output
LONDON TOWERBRIDGE

7. 2. RAISED WEIGHT
ACCUMULATOR
A raised weight accumulator consists of a
vertical cylinder containing fluid to the
hydraulicline.
The cylinder is closed by a piston on which a
series of weights are placed that exert a
downward force on the piston and thereby
energizes thefluid in the cylinder.
Gravity acts on the weight to pressurize
the hydraulic system fluid, thus storing
energy.

8. ADVANTGES :
Used to meet heavy industrial
requirements.
Extremely high capacity at lowcost.
Rugged and durable construction.
LIMITATIONS :
Extremely bulky and heavy.
Problem in sealing.
Hydraulic engine
house, Bristol Harbor.

9. 3. COMPRESSED GAS
ACCUMULATOR
It is widely used accumulator in presentscenario.
It is popularly known as “hydro-pneumatic accumulator”.
It apply force to the liquid by using a compressed gas that acts as the
spring.
It uses inert gas (nitrogen) under pressure that provides the compressive
force onfluid.
Oxygen is not used because oxygen and oil can form anexplosivee mixture
when combined underpressure
As the volume of the compressed gas changes the pressure of the gas,
and pressure of the fluid, changes inversely.

10. 4. Spring type
accumulator
It uses the energy stored in springs to create a constant force .
The load characteristics of a spring are such that the energy
storage depends on the force required to compress sspring.
The free (uncompressed) length of a spring represents zero energy
storage.
As liquid under pressure enters the cylinder, causing a spring to
compress, the pressure on the liquid will rise because of the
increased loading required to compress the spring.

11. HYDARULIC
SYMBOLS

12. FUNCTIONS : Where are
accumulators used?
Accumulators can be applied creatively in any number of
situations, including:
Shock or pulsation dampening: An accumulator can be used to cushion
the pressure spike from sudden valve closure, the pulsation from pumps
or the load reaction from sudden movement of parts connected to
hydrauliccylinders.
Leakage compensation: An accumulator can be used to maintain
pressure and make-up for lost fluid due to internal leakage of system
components including cylinders and valves.
Thermal expansion: An accumulator can absorb the pressure
differences caused by temperature variations in a closed hydraulic system.

13. Energy conservation
Improved response times: An accumulator (bladder type) has virtually
instantaneous response time that can provide fluid very quickly to fast-acting
valves such as servos and proportional to improve theireffectiveness

14. ACCUMULATOR DESIGN
CONSIDERATION :
Accumulator type
Accumulator volume
Nominal hydraulic system pressure
Minimum and Maximum hydraulic system pressure
Pre-charge pressure
Required flow rate
Output volume capacity
Recharge time
Response time
Fluid type

15. APPLICATIO
NS
Accumulators are devices used to store fluid power to dothe
following:
Agricultural Machinery & Equipment.
Forestry Equipment.
Oil Field & Offshore.
Machine Tools and Off- Road Equipment.
Mining Machinery & Equipment.
Construction Equipment.
Suspension in vehicles.

16. ADVANTA
GE
Lower installed system costs, accumulator assisted hydraulics can reduce
the size of the pump and electric motor which results in a smaller amount
of oil used, a smaller reservoir and reduced equipmentcosts.
Less leakage and maintenance costs, the ability to reduce system shocks will
prolong component life, reduce leakage from pipe joints and minimize
hydraulic system maintenance costs.
Improved performance, low inertia bladder accumulators can provide
instantaneous response time to meet peak flow requirements. They can also
help to achieve constant pressure in systems using variable displacement pumps
for improved productivity and quality.

17. Reduced noise levels, reduced pump and motor size couple with system
shock absorption overall machine sound levels and results in higher
operator productivity.
Flexible design approaches. A wide range of accumulator types and
sizes, including accessory items, provides a versatile and easy to
apply design approach.
Reduced energy costs, cost savings of up to 33% are achievable in high
performance industrial machinery using accumulators.
ADVANTAGE

18. HYDRAULIC INTENSIFIER

19. It is a device used for producing high pressure liquid by using the
energy of larger amount of liquid at low pressure.
HYDRAULIC INTENSIFIER

20. COMPONENTS USED
FIXED RAM .
SLIDING CYLINDER OR RAM.
FIXED CYLINDER .
VALVES.

21. HYDRAULIC INTENSIFIER

22. TYPES OF INTENSIFIERS
Single acting intensifier: as it supplies high pressure liquid during downward
stroke only.
Double acting intensifier: it gives continuous supply of high pressure liquid.

23. APPLICATION OF MACHINES
It is required in hydraulic machines such as hydraulic presses which requires
fluid at high pressure. And the pump cannot provide high pressure fluid
therefore a hydraulic intensifier is placed in between the pump and
machine which would supply high pressure fluid.
Air operated hydraulic intensifier are used commonly for clamping, holding,
punching,presses , jacks ,torque wrenches