hydrolic pipe bending machine

7/25/2019 Hydrolic Pipe Bending Machine

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HYDRAULIC OPERATED V TYPE BENDING

MACHINE

SYNOPSIS

In this project the bending of v shaped rod is carried with the help of hydraulic jack

arrangements. This method is very useful in industries to convert the lengthiest metal rod to the v

shaped type. Here the main aim of our project is reduce the man power, applying constant force

at all time , automating the process and also increase the rate of production.


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CHAPTER 1

INTRODUCTION

A Hydraulic cylinder (also called a linear hydraulic motor) is a mechanical actuator that

is used to give a unidirectional force through a unidirectional stroke. It has many applications,

notably in engineering vehicles, industrial application, civil applications.

Hydraulic cylinders get their power from pressurized hydraulic fluid, which is typically

oil, air. The hydraulic cylinder consists of a cylinder barrel, in which a piston connected to a

piston rod moves back and forth. The barrel is closed on one end by the cylinder bottom (also

called the cap) and the other end by the cylinder head (also called the gland) where the piston rod

comes out of the cylinder. The piston has sliding rings and seals. The piston divides the inside of

the cylinder into two chambers, the bottom chamber (cap end) and the piston rod side chamber

(rod end / head end).

Flanges, trunnions, clevises, Lugs are common cylinder mounting options. The piston rod

also has mounting attachments to connect the cylinder to the object or machine component that it

is pushing / pulling. A hydraulic cylinder is the actuator or "motor" side of this system. The

"generator" side of the hydraulic system is the hydraulic pump which brings in a fixed or

regulated flow of oil to the hydraulic cylinder, to move the piston. The piston pushes the oil in

the other chamber back to the reservoir.

Hydraulic machines are machinery and tools that use liquid fluid power to do simple

work. Heavy equipment is a common example. In this type of machine, hydraulic fluid is

transmitted throughout the machine to various hydraulic motors and hydraulic cylinders and
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which becomes pressurized according to the resistance present. The fluid is controlled directly or

automatically bycontrol valves and distributed throughhoses andtubes.

The popularity of hydraulic machinery is due to the very large amount of power that can

be transferred through small tubes and flexible hoses, and the high power density and wide array

of actuators that can make use of this power. Hydraulic machinery is operated by the use of

hydraulics, where a liquid is the powering medium.

Parts of a hydraulic cylinder

A hydraulic cylinder consists of the following parts:

Cylinder barrel

The main function of cylinder body is to hold cylinder pressure. The cylinder barrel is

mostly made from a seamless tube. The cylinder barrel is ground and/or honed internally with a

typical surface finish of 4 to 16 micro inch. Normally hoop stresses are calculated to optimize the

barrel size.

Cylinder base or cap

The main function of cap is to enclose the pressure chamber one end. The cap is

connected to the body by means of welding, threading, bolts, tie rod. Cap also perform as a

cylinder mounting components. Cap size determined based on the bending stress.
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Cylinder head

The main function of head is to enclose the pressure chamber from other end. Head

contains an integrated rod sealing arrangement or option to accept a seal gland. The head is

connected to the body by means of threading, bolts, tie rod. A static seal / o-ring used in between

head and barrel.

Piston

The main function of piston is to separate pressure zone in side barrel. The piston is

machined with grooves to fit elastomeric or metal seals and bearing elements. These seals can be

single acting or double acting. This difference in pressure between the two sides of the piston

causes the cylinder to extend and retract. Piston is attached with the piston rod by means of

threads, bolts, nuts to transfer the linear motion.

Piston rod

The piston rod is typically a hard chrome-plated piece of cold-rolled steel which attaches

to the piston and extends from the cylinder through the rod-end head. In double rod-end

cylinders, the actuator has a rod extending from both sides of the piston and out both ends of the

barrel. The piston rod connects the hydraulic actuator to the machine component doing the work.

This connection can be in the form of a machine thread or a mounting attachment.

Seal gland

The cylinder head is fitted with seals to prevent the pressurized oil from leaking past the

interface between the rod and the head. This area is called the seal gland. The advantage of seal


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gland is easy removal and seal replacement. The seal gland contains primary seal, secondary seal

/ buffer seal, bearing elements, wiper / scraper and static seal. In some cases, especially in small

hydraulic cylinders, the rod gland and the bearing elements are made from a single integral

machined part.

Seals

The seals are considered / design as per the cylinder working pressure, cylinder speed,

operating temperature, working medium and application. Piston seals are dynamic seals, can be

single acting or double acting. Generally speaking, Elastomers seals made from nitrile rubber,

Polyurethane or other materials are best in lower temperature environments, while seals made of

Fluorocarbon Viton are better for higher temperatures. Metallic seals are also available

commonly used cast iron for seal material. Rod seal are dynamic seals and generally single

acting.

The compounds of rod seals arenitrile rubber,Polyurethane, FluorocarbonViton.Wiper

/ scraper are used to eliminates contaminants such as moisture, dirt, and dust, which can cause

extensive damage to cylinder walls, rods, seals and other components. The common compound

for wiper is polyurethane. Metallic scraper are used for sub zero temperature application,

application where foreign material can deposit on rod. The bearing element / wear bands are use

to eliminate metal to metal contact. The wear bands are design as per the side load requirements.

The primary compounds for wear bands are filled PTFE, Woven fabric reinforced polyester

resin, bronze.
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HYDRAULIC OPERATED BENDING MACHINE

Three hardened driving rolls with smooth surface

Nr. 3 hydraulic motors directly keyed on the rolls

Independent regulation of the 2 bottom rolls by hydraulic cylinders controlled from

control desk for pre-bending and bending operations

Correcting rolls with movements in 3 dimensions and roll to straighten leg-out and leg-

in angle profiles and asymmetrical profiles

Flexible positioning horizontal or vertical

Detached control desk movable on wheels with nr.2 digital readouts

Nr. 9 rolls to bend the most common profiles

Three hardened driving rolls with smooth surface

This machine consist of a series of tube V-Type bending machines, which are of the best

quality and assure long term durability. Owing to their functional utility, these machines are

widely used for producing components with multiple bends in a single plane.


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Features:

No. of multi-plane bends settable = 8 (POB & DBB) [in NCXR series]

Minimum 1.5D / 2D bending, based on model

User-friendly microprocessor based numerical controller 'SMARTBEND 410'

with color LCD monitor and keyboard access, advanced on-line diagnostics,

display of on-going process, status of inputs/outputs and error messages

Bend angle range = 5 to 180 degrees (DOB)

Programmable DOB in automatic open loop control

Pre-selectable POB [in NCXR series]

Memory capacity of 1000 programs with 15 bends per program

Precision bending tooling to suit your component

Manifold style hydraulics

Perfect quality bends by programmable bending angle and preset bending

sequence

Note:D = tube outside diameter; t = tube wall thickness; Q = centre line radius; DOB = degree

of bend; POB = plane or bent DBS = distance between bends


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Other information:

The NCX tube bending machines have a clamping die, pressure die, mandrel and bend

head, which are all hydraulically operated. To enhance the usefulness of these NCX machines,

Electro pneumatics has developed the NCXR Series.

These tube bending machines have a pre-settable linear and rotary indexing facility for

multi-plane bends, in addition to the clamp, pressure die, mandrel and bend arm. These

hydraulic, semi-automatic machines can handle tubes from 6 mm to 325 mm outside diameter, ft

is possible to bend tubes of a variety of materials with round, square or rectangular sections and

different profiles, which eliminates the need for locating fixtures on the machine. A carriage with

a manual/hydraulic chucking arrangement that is capable of traversing the length of the machine

is provided.

Electro pneumatics user-friendly programmable microprocessor based numerical 'Smart

bend 4101 series controllers are specially designed for these machines. With these machines, all

operations of the bending process are done automatically, while rotation and linear orientation of

the component between two bends is done manually by the operator against pre-settable stops.


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INTENDED USE:

The Hydraulic Pipe Bender is designed for bending thick-walled pipes (black iron,

schedule 40 &80, etc.). There are six different bending dies ranging from 1/2" to 2" for Item#

141805, eight different bending dies ranging from 1/2" to 3" for Item# 426261 and nine different

bending dies ranging from 1/2" to 4" for Item# 426260. The Hydraulic Pipe Bender is not

designed for bending thin-walled Pipes.

SALIENT FEATURES OF HYDRAULIC OPERATED MACHINES

All machines are made of high quality graded castings, which are properly aged and

stress relieved using vibratory stress relieving equipments, for taking care of any seasonal

effects on castings. Thus enhancing the life of machines.

All the machines are hand scrapped for long lasting precision and reliability. The

Hydraulic series machines are designed with the principles of column movement (Y

axis). This enhances the overall life of machine and provides high accuracy for jobs for

many years.


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The hydraulic pumps are designed specially for surface grinding machine in house. These

pumps provide smooth, vibration free movements for superior job finishes.

The slides (X & Y) are coated with turcite lining, a slide way material with special

embedding properties, this considerably reduces the friction between slides for very easy

and smooth movement thereby reducing wear & tear of machines to a large extent.

All the three axis as well as cross feed and vertical screws are continuously lubricated

with specially designed inbuilt lubricating system. This not only makes the machine very

easy to operate but also reduces wear and tear of all moving parts.

All the machines come with special spindles assembled with high quality low vibration

motors, as well as fitted with very high quality imported bearings which are greased

packed for life, providing a very precise grinding action for best surface finishes as well

as best flatness for jobs.

All hydraulic machines come with specially designed moveable tower electrical panel.

These panels provide easy to use functions for operation of machines. Panels have been

provided with sufficient interlocks for accident free operations.

All the electrical and other bought out items are of high quality and from reputed brands.

Care is taken that such items are easily available in market for easy maintenance and

replacements.

Our machines are backed with 1 year workmanship guarantee providing peace of minds

to customers.


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Design Considerations

Pressure and Temperature ratings

Interlocks for sequential operations

Emergency shutdown features

Power failure locks

Operation speed

Environment conditions

Efficiency of Operation

Keep system Simple, Safe and Functional

Access to parts need repair or adjustment

Design to keep min operational cost

Design to prevent and remove contamination

Hydraulic bending machine, including brackets, table and clamping plate, the table

placed in the bracket, Workbench from the platen base and base connected by a hinge and the

clamping plate, the base of the seat shell, coil and cover, coil placed in the seat shell depression,

the depression at the top covered with a lid. used by the wire coil is energized, power on the

platen gravity, thereby clamping the sheet between the platen and the base due to the

electromagnetic force folder hold the plate can be made into a variety of workpiece

requirements, but also on the sidewall of the work piece to be processed.


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USES OF HYDRAULIC BENDING MACHINE

Our range of Hydraulic Breading Machine is used for selectively dispensing flour

breading or free flowing breading onto a food product wherein the machine has a frame and

conveyor structure supported on the frame defining a conveyance path having a product inlet end

and a product outlet end. This machine also comes with a breading hopper attached to the frame

adjacent to the inlet end for applying a coating of breading to the food product and also a

breading pumping slot structure attached to the frame for providing breading to the input end of

the conveyor with a fluffier mechanism mounted on the pumping slot structure to break up any

caking or lumping of the breading on the conveyor prior to the point of introduction of the food

product to the conveyor.

The Mechanical Screw jacks have been replaced with hydraulically operated jacks. This

reduces requirement of man power upto 40% and the Roll bending cycle time is reduced by 40%.

The Machine has a capacity to pre bend but with a flat edge of 40% of Top Roll Dia of the

machine. It is not out of place to highlight that the pre bend capacity of a given Plate Bending

machine is approximately 80% of its roll bending capacity, i.e, A plate bending machine having

a capacity of 16 mm thick is capable of Pre bending plates upto 12 mm thickness when equipped

with hydraulically operated jacks.

Nevertheless the reduced man power and production makes for the flat edge. The machine

is priced almost less than half of the machines doing the same job across the globe. The fact

remains that not a single machine is available which has zero flat edge. The minimum flat edge is

generally 3 to 6 times the thickness of the plate being bent.


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The Machines have longer functional life, consumes less electricity and ensures optimum

performance. In addition to these features, offered range is best alternative to CNC bending

machines, it has appreciating production capacity. The range produces wrinkle free, smooth

bends and it is also an interchangeable set of tooling for each type of bend. Our range has

aforementioned features as we use best quality raw material for its manufacturing under the eye

of professionals.

A hydraulic drive system is a drive ortransmission system that uses pressurizedhydraulic

fluid to drive hydraulic machinery.The term hydrostatic refers to the transfer of energy from

flow and pressure, not from thekinetic energy of the flow.

A hydraulic drive system consists of three parts: The generator (e.g. ahydraulic pump),

driven by an electric motor,a combustion engine or a windmill;valves, filters, piping etc. (to

guide and control the system); the motor (e.g. ahydraulic motor orhydraulic cylinder)to drive

the machinery.

Principles of Hydraulic Drive

Pascal's law is the basis of hydraulic drive systems. As the pressure in the system is the

same, the force that the fluid gives to the surroundings is therefore equal to pressure area. In

such a way, a small piston feels a small force and a large piston feels a large force.

The same principle applies for a hydraulic pump with a small swept volume that asks for

a small torque,combined with a hydraulic motor with a large swept volume that gives a large

torque. In such a way a transmission with a certain ratio can be built.
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Most hydraulic drive systems make use of hydraulic cylinders. Here the same principle is

useda small torque can be transmitted in to a large force.By throttling the fluid between the

generator part and the motor part, or by using hydraulic pumps and/or motors with adjustable

swept volume, the ratio of the transmission can be changed easily. In case throttling is used, the

efficiency of the transmission is limited. In case adjustable pumps and motors are used, the

efficiency, however, is very large. In fact, up to around 1980, a hydraulic drive system had

hardly any competition from other adjustable drive systems.

Nowadays, electric drive systems using electric servo-motors can be controlled in an

excellent way and can easily compete with rotating hydraulic drive systems. Hydraulic cylinders

are, in fact, without competition for linear forces. For these cylinders, hydraulic systems will

remain of interest and if such a system is available, it is easy and logical to use this system for

the rotating drives of the cooling systems, also.

Hydraulic Press


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A hydraulic is a machine using ahydraulic cylinder to generate a compressive force. It

uses the hydraulic equivalent of a mechanical lever,and was also known as a Bramah press after

the inventor,Joseph Bramah,of England. He invented and was issued a patent on this press in

1795. As Bramah (who is also known for his development of the flush toilet) installed toilets, he

studied the existing literature on the motion of fluids and put this knowledge into the

development of the press.

Hydraulic Motor:

The hydraulic motor is the rotary counterpart of the hydraulic cylinder.Conceptually, a

hydraulic motor should be interchangeable with thehydraulic pump,due to the fact it performs

the opposite function. However, most hydraulic pumps cannot be used as hydraulic motors

because they cannot be backdriven. Also, a hydraulic motor is usually designed for the working

pressure at both sides of the motor. Another difference is that a motor can be reversed by a

reversing valve.
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Pressure in a hydraulic system is like the voltage in an electrical system and fluid flow

rate is the equivalent of current. The size and speed of the pump determines the flow rate, the

load at the motor determines the pressure.

Hydraulic Valves:

These valves are usually very heavy duty to stand up to high pressures. Some special

valves can control the direction of the flow of fluid and act as a control unit for a system.

Classification of hydraulic valves

Classification based on function:

1. Pressure control valves(PC Valves)

2. Flow control valves (FC Valves)

3. Direction control valves (DC Valves)

Classification based on method of activation:

1. Directly operated valve

2. Pilot operated valve

3. Mutually operated valve

4. Electrically actuated valve

5. open control valve

6. Servo controlled valves


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Structure and characteristics of the hydraulic bending machine:

1. All-steel welded construction of sufficient strength and rigidity.

2. Hydraulic drive, the machine at both ends of the fuel tank is placed in the slider on the

direct drive slide work.

3. Slider synchronization mechanism with torsion bar forced synchronization.

4. Using the machinery of block structure, stable and reliable.

5. Slide stroke motor fast tune, manual fine tuning, counter display

5. The Wedge deflection compensation mechanism to ensure that the higher bending

accuracy.

Lifting and installation of hydraulic bending machine

Lifting and installation of hydraulic plate bending machine, hydraulic plate bending

machine and the whole center of gravity higher, before re-light, so the process of lifting and

handling and installation should be noted that the center of gravity, so as not to cause the

machine to turn over accident, lifting, lifting wire angle as small as possible, the same to ensure

that the machine precision. hydraulic plate bending machine left and right columns in the work

surface at the benchmark for measuring the level of vertical and horizontal direction should be

less than or equal to 1000: 0.2, according to the foundation plan in advance, prepare the ground,

the hydraulic plate bending machine is installed on the basis of, and install anchor bolts, the final

grouting be all solidified cement retaining screws, proof-reading level.


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CHAPTER 2

BASIC COMPONENTS

Hydraulic pump

Hydraulic pump

Hydraulic pumps supply fluid to the components in the system. Pressure in the system

develops in reaction to the load. Hence, a pump rated for 5,000 psi is capable of maintaining

flow against a load of 5,000 psi.

Pumps have apower density about ten times greater than an electric motor (by volume).

They are powered by an electric motor or an engine, connected through gears, belts, or a flexible

elastomeric coupling to reduce vibration.
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Common types of hydraulic pumps to hydraulic machinery applications are;

Gear pump:cheap, durable (especially in g-rotor form)., simple. Less efficient, because

they are constant (fixed) displacement, and mainly suitable for pressures below 20 MPa

(3000 psi).

Vane pump:cheap and simple, reliable.Good for higher-flow low-pressure output.

Axial piston pump:many designed with a variable displacement mechanism, to vary

output flow for automatic control of pressure. There are various axial piston pump

designs, including swashplate (sometimes referred to as a valveplate pump) and checkball

(sometimes referred to as a wobble plate pump). The most common is the swashplate

pump. A variable-angleswashplate causes the pistons to reciprocate a greater or lesser

distance per rotation, allowing output flow rate and pressure to be varied (greater

displacement angle causes higher flow rate, lower pressure, and vice versa).

Radial piston pump:A pump that is normally used for very high pressure at small flows.

Piston pumps are more expensive than gear or vane pumps, but provide longer life operating at

higher pressure, with difficult fluids and longer continuous duty cycles. Piston pumps make up

one half of ahydrostatic transmission.

Control valves
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Directional control valvesroute the fluid to the desired actuator. They usually consist of

a spool inside acast iron orsteel housing. The spool slides to different positions in the housing,

intersecting grooves and channels route the fluid based on the spool's position.

The spool has a central (neutral) position maintained with springs; in this position the

supply fluid is blocked, or returned to tank. Sliding the spool to one side routes the hydraulic

fluid to an actuator and provides a return path from the actuator to tank. When the spool is

moved to the opposite direction the supply and return paths are switched. When the spool is

allowed to return to neutral (center) position the actuator fluid paths are blocked, locking it in

position. Directional control valves are usually designed to be stackable, with one valve for each

hydraulic cylinder, and one fluid input supplying all the valves in the stack.

Tolerances are very tight in order to handle the high pressure and avoid leaking, spools

typically have a clearance with the housing of less than a thousandth of an inch (25 m). The

valve block will be mounted to the machine's frame with a three pointpattern to avoid distorting

the valve block and jamming the valve's sensitive components.

The spool position may be actuated by mechanical levers, hydraulic pilot pressure, or

solenoids which push the spool left or right. Aseal allows part of the spool to protrude outside

the housing, where it is accessible to the actuator.

The main valve block is usually a stack of off the shelfdirectional control valves chosen by

flow capacity and performance. Some valves are designed to be proportional (flow rate

proportional to valve position), while others may be simply on-off. The control valve is one of

the most expensive and sensitive parts of a hydraulic circuit.
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Pressure relief valves are used in several places in hydraulic machinery; on the return

circuit to maintain a small amount of pressure for brakes, pilot lines, etc., On hydraulic

cylinders, to prevent overloading and hydraulic line/seal rupture. On the hydraulic

reservoir, to maintain a small positive pressure which excludes moisture and

contamination.

Pressure regulatorsreduce the supply pressure of hydraulic fluids as needed for various

circuits.

Sequence valvescontrol the sequence of hydraulic circuits; to ensure that one hydraulic

cylinder is fully extended before another starts its stroke, for example.

Shuttle valvesprovide a logicalor function.

Check valves are one-way valves, allowing an accumulator to charge and maintain its

pressure after the machine is turned off, for example.

Pilot controlled Check valves are one-way valve that can be opened (for both

directions) by a foreign pressure signal. For instance if the load should not be held by the

check valve anymore. Often the foreign pressure comes from the other pipe that is

connected to the motor or cylinder.

Counterbalance valves are in fact a special type of pilot controlled check valve.

Whereas the check valve is open or closed, the counterbalance valve acts a bit like a pilot

controlled flow control.

Cartridge valves are in fact the inner part of a check valve; they are off the shelf

components with a standardized envelope, making them easy to populate a proprietary

valve block. They are available in many configurations; on/off, proportional, pressure
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relief, etc. They generally screw into a valve block and are electrically controlled to

provide logic and automated functions.

Hydraulic fusesare in-line safety devices designed to automatically seal off a hydraulic

line if pressure becomes too low, or safely vent fluid if pressure becomes too high.

Auxiliary valves in complex hydraulic systems may have auxiliary valve blocks to

handle various duties unseen to the operator, such as accumulator charging, cooling fan

operation, air conditioning power, etc. They are usually custom valves designed for the

particular machine, and may consist of a metal block with ports and channels drilled.

Cartridge valves are threaded into the ports and may be electrically controlled by

switches or a microprocessor to route fluid power as needed.

Actuators

Hydraulic cylinder

Swashplates are used in 'hydraulic motors' requiring highly accurate control and also in

'no stop' continuous (360) precision positioning mechanisms. These are frequently

driven by several hydraulic pistons acting in sequence.

Hydraulic motor (a pump plumbed in reverse)

hydrostatic transmission

Brakes

Reservoir

The hydraulic fluid reservoir holds excess hydraulic fluid to accommodate volume

changes from: cylinder extension and contraction, temperature driven expansion and contraction,
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and leaks. The reservoir is also designed to aid in separation of air from the fluid and also work

as a heat accumulator to cover losses in the system when peak power is used. Design engineers

are always pressured to reduce the size of hydraulic reservoirs, while equipment operators

always appreciate larger reservoirs. Reservoirs can also help separate dirt and other particulate

from the oil, as the particulate will generally settle to the bottom of the tank.

Some designs include dynamic flow channels on the fluid's return path that allow for a

smaller reservoir.

Accumulators

Accumulators are a common part of hydraulic machinery. Their function is to store

energy by using pressurized gas. One type is a tube with a floating piston. On one side of the

piston is a charge of pressurized gas, and on the other side is the fluid. Bladders are used in other

designs. Reservoirs store a system's fluid.

Examples of accumulator uses are backup power for steering or brakes, or to act as a

shock absorber for the hydraulic circuit.

Hydraulic fluid

Also known as tractor fluid, hydraulic fluid is the life of the hydraulic circuit. It is usually

petroleum oil with various additives. Some hydraulic machines require fire resistant fluids,

depending on their applications. In some factories where food is prepared, either an edible oil or

water is used as a working fluid for health and safety reasons.
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In addition to transferring energy, hydraulic fluid needs tolubricate components, suspend

contaminants and metal filings for transport to the filter, and to function well to several hundred

degrees Fahrenheit or Celsius.

Filters

Filters are an important part of hydraulic systems. Metal particles are continually

produced by mechanical components and need to be removed along with other

contaminants.Filters may be positioned in many locations. The filter may be located between the

reservoir and the pump intake. Blockage of the filter will causecavitation and possibly failure of

the pump. Sometimes the filter is located between the pump and the control valves. This

arrangement is more expensive, since the filter housing is pressurized, but eliminates cavitation

problems and protects the control valve from pump failures. The third common filter location is

just before the return line enters the reservoir. This location is relatively insensitive to blockage

and does not require a pressurized housing, but contaminants that enter the reservoir from

external sources are not filtered until passing through the system at least once.

Tubes, pipes and hoses

Hydraulictubesare seamless steel precision pipes, specially manufactured for hydraulics.

The tubes have standard sizes for different pressure ranges, with standard diameters up to

100 mm. The tubes are supplied by manufacturers in lengths of 6 m, cleaned, oiled and plugged.

The tubes are interconnected by different types of flanges (especially for the larger sizes and

pressures), welding cones/nipples (with o-ring seal), several types of flare connection and by cut-
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rings. In larger sizes, hydraulic pipes are used. Direct joining of tubes by welding is not

acceptable since the interior cannot be inspected.

Hydraulic pipe is used in case standard hydraulic tubes are not available. Generally these are

used for low pressure. They can be connected by threaded connections, but usually by welds.

Because of the larger diameters the pipe can usually be inspected internally after welding.Black

pipe isnon-galvanized and suitable forwelding.

Hydraulichoseis graded by pressure, temperature, and fluid compatibility. Hoses are used when

pipes or tubes can not be used, usually to provide flexibility for machine operation or

maintenance. The hose is built up with rubber and steel layers. A rubber interior is surrounded by

multiple layers of woven wire and rubber. The exterior is designed for abrasion resistance. The

bend radius of hydraulic hose is carefully designed into the machine, since hose failures can be

deadly, and violating the hose's minimum bend radius will cause failure. Hydraulic hoses

generally have steel fittings swaged on the ends. The weakest part of the high pressure hose is

the connection of the hose to the fitting. Another disadvantage of hoses is the shorter life of

rubber which requires periodic replacement, usually at five to seven year intervals.

Tubes and pipes for hydraulic applications are internally oiled before the system is

commissioned. Usually steel piping is painted outside. Where flare and other couplings are used,

the paint is removed under the nut, and is a location where corrosion can begin. For this reason,

in marine applications most piping is stainless steel.
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Seals, fittings and connections

In general,valves,cylinders andpumps havefemale threaded bosses for the fluid

connection, and hoses have female ends with captive nuts. A male-male fitting is chosen to

connect the two. Many standardized systems are in use.

Fittings serve several purposes;

1. To bridge different standards;O-ring boss toJIC,orpipe threads toface seal,for

example.

2. To allow proper orientation of components, a 90, 45, straight, or swivel fitting is

chosen as needed. They are designed to be positioned in the correct orientation and then

tightened.

3. To incorporate bulkhead hardware.

4. A quick disconnectfitting may be added to a machine without modification of hoses or

valves

A typical piece of heavy equipment may have thousands of sealed connection points and several

different types:

Pipe fittings,the fitting is screwed in until tight, difficult to orient an angled fitting

correctly without over or under tightening.

O-ring boss, the fitting is screwed into a boss and orientated as needed, an additional nut

tightens the fitting, washer ando-ring in place.

Flare fittings,are metal to metal compression seals deformed with a cone nut and pressed

into a flare mating.
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CHAPTER 3

METHODOLOGY

The project is designed by following equipments:

Compressor

control unit

Solenoid valve

pneumatic cylinder

Mechanical model

Hydraulic jack

The working of the process is fully pneumatic and hydraulic operated where the air

is working medium. In this unit compressor is used to supply the compressed air at certain

pressure. This pressurized air is passed to the solenoid valve. The solenoid valve is controlled by

control unit. This solenoid valve is used to control the direction of flow of air to the pneumatic

cylinder. In this pneumatic cylinder the piston rod actuates due to the pressure.

At the end of piston rod bending tool is attached. So that tool bends the rod into

required v shape. Thus the work piece clamped on the frame is bending due to the reciprocating

motion of the bend.

EQUIPMENT DESCRIPTION

Compressor:

A gas compressor is a mechanical device that increases the pressure of a gas by reducing

its volume. Compressors are similar to pump: both increase the pressure on a fluid and both can

transport the fluid through a pipe. As gases are compressible, the compressor also reduces the


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volume of a gas. Liquids are relatively incompressible; while some can be compressed, the main

action of a pump is to pressurize and transport liquids.

Centrifugal compressorsuse a rotating disk orimpeller in a shaped housing to force the

gas to the rim of the impeller, increasing the velocity of the gas. A diffuser (divergent duct)

section converts the velocity energy to pressure energy. They are primarily used for continuous,

stationary service in industries such as oil refineries, chemical and petrochemical plants and

natural gas processing plants. Their application can be from 100 horsepower (75 kW) to

thousands of horsepower. With multiple staging, they can achieve extremely high output

pressures greater than 10,000 psi (69 MPa).

Many large snowmaking operations (likeski resorts)use this type of compressor. They

are also used in internal combustion engines as superchargers and turbochargers. Centrifugal

compressors are used in small gas turbineengines or as the final compression stage of medium

sized gas turbines. Sometimes the capacity of the compressors is written in NM3/hr. Here 'N'

stands for normal temperature pressure (20C and 1 atm) for example 5500 NM3/hr.

Axial-flow compressors are dynamic rotating compressors that use arrays of fan-like

airfoils to progressively compress the working fluid. They are used where there is a requirement

for a high flow rate or a compact design.

The arrays of airfoils are set in rows, usually as pairs: one rotating and one stationary.

The rotating airfoils, also known as blades or rotors, accelerate the fluid. The stationary airfoils,

also known asstatorsor vanes, decelerate and redirect the flow direction of the fluid, preparing it

for the rotor blades of the next stage. Axial compressors are almost always multi-staged, with the
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cross-sectional area of the gas passage diminishing along the compressor to maintain an

optimum axial Mach number. Beyond about 5 stages or a 4:1 design pressure ratio, variable

geometry is normally used to improve operation.

Axial compressors can have high efficiencies; around 90% polytropic at their design

conditions. However, they are relatively expensive, requiring a large number of components,

tight tolerances and high quality materials. Axial-flow compressors can be found in medium to

largegas turbine engines, in natural gas pumping stations, and within certain chemical plants.

Reciprocating compressors use pistons driven by a crankshaft. They can be either

stationary or portable, can be single or multi-staged, and can be driven by electric motors or

internal combustion engines. Small reciprocating compressors from 5 to 30horsepower (hp) are

commonly seen in automotive applications and are typically for intermittent duty. Larger

reciprocating compressors well over 1,000 hp (750 kW) are commonly found in large industrial

and petroleum applications. Discharge pressures can range from low pressure to very high

pressure (>18000 psi or 180 MPa). In certain applications, such as air compression, multi-stage

double-acting compressors are said to be the most efficient compressors available, and are

typically larger, and more costly than comparable rotary units.[6]Another type of reciprocating

compressor is the swash plate compressor, which uses pistons moved by a swash plate mounted

on a shaft (seeaxial piston pump.

Household, home workshop, and smaller job site compressors are typically reciprocating

compressors 1 hp or less with an attached receiver tank.
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Control Unit:

The control unitcoordinates the components of a computer system. It fetches the code of

all of the instructions in the program. It directs the operation of the other units by providing

timing and control signals. All computer resources are managed by the CU. It directs the flow of

data between the Central Processing Unit (CPU) and the other devices.

The control unit was historically defined as one distinct part of the 1946 reference model

of Von Neumann architecture. In modern computer designs, the control unit is typically an

internal part of theCPU with its overall role and operation unchanged.

The control unit is the circuitry that controls the flow of data through the processor, and

coordinates the activities of the other units within it. In a way, it is the "brain within the brain",

as it controls what happens inside the processor, which in turn controls the rest of the computer.

The examples of devices that require a control unit are CPUs and graphics processing units

(GPUs). The modern information age would not be possible without complex control unit

designs. The control unit receives external instructions or commands which it converts into a

sequence of control signals that the control unit applies to the data path to implement a sequence

ofregister-transfer level operations.

Hardwired control units are implemented through use ofsequential logic units, featuring

a finite number of gates that can generate specific results based on the instructions that were used

to invoke those responses. Hardwired control units are generally faster than microprogrammed

designs.
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Their design uses a fixed architecture it requires changes in the wiring if the

instruction set is modified or changed. This architecture is preferred in reduced instruction set

computers (RISC) as they use a simpler instruction set. The hardwired approach has become less

popular as computers have evolved as at one time, control units for CPUs were ad-hoc logic, and

they were difficult to design.

The idea of microprogramming was introduced by Maurice Wilkes in 1951 as an

intermediate level to execute computer program instructions. Microprograms were organized as a

sequence of microinstructionsand stored in special control memory.

The algorithm for the microprogram control unit is usually specified by flowchart

description. The main advantage of the microprogram control unit is the simplicity of its

structure. Outputs of the controller are organized in microinstructions and they can be easily

replaced.

The control unit implements the instruction set of the CPU. It performs the tasks of

fetching, decoding, managing execution and then storing results. It may manage the translation

of instructions (not data) to micro-instructions and manage scheduling the micro-instructions

between the various execution units.

On some processors the control unit may be further broken down into other units, such

as a scheduling unit to handle scheduling and a retirement unit to deal with results coming from

the pipeline; It is the main function of CPU.
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Solenoid Valve:

A solenoid valve is an electromechanically operated valve. The valve is controlled by an

electric current through a solenoid: in the case of a two-port valve the flow is switched on or off;

in the case of a three-port valve, the outflow is switched between the two outlet ports. Multiple

solenoid valves can be placed together on a manifold.

Solenoid valves are the most frequently used control elements in fluidics. Their tasks are

to shut off, release, dose, distribute or mix fluids. They are found in many application areas.

Solenoids offer fast and safe switching, high reliability, long service life, good medium

compatibility of the materials used, low control power and compact design.

A solenoid valve has two main parts: the solenoid and the valve. The solenoid converts

electrical energy into mechanical energy which, in turn, opens or closes the valve mechanically.


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A direct actingvalve has only a small flow circuit, shown within section E of this diagram (this

section is mentioned below as a pilot valve). In this example, a diaphragm piloted valve

multiplies this small pilot flow, by using it to control the flow through a much larger orifice.

Solenoid valves may use metal seals or rubber seals, and may also have electrical interfaces to

allow for easy control. A spring may be used to hold the valve opened (normally open) or closed

(normally closed) while the valve is not activated.

The diagram to the right shows the design of a basic valve, controlling the flow of water

in this example. At the top figure is the valve in its closed state. The water under pressure enters

at A. Bis an elastic diaphragm and above it is a weak spring pushing it down. The function of

this spring is irrelevant for now as the valve would stay closed even without it. The diaphragm

has a pinhole through its center which allows a very small amount of water to flow through it.

This water fills the cavity Con the other side of the diaphragm so that pressure is equal on both

sides of the diaphragm, however the compressed spring supplies a net downward force. The

spring is weak and is only able to close the inlet because water pressure is equalized on both

sides of the diaphragm.

In the previous configuration the small passage D was blocked by a pin which is the

armature of the solenoid Eand which is pushed down by a spring. If the solenoid is activated by

drawing the pin upwards via magnetic force from the solenoid current, the water in chamber C

will flow through this passage Dto the output side of the valve. The pressure in chamber Cwill

drop and the incoming pressure will lift the diaphragm thus opening the main valve. Water now

flows directly from Ato F.


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When the solenoid is again deactivated and the passage D is closed again, the spring

needs very little force to push the diaphragm down again and the main valve closes. In practice

there is often no separate spring, the elastomer diaphragm is molded so that it functions as its

own spring, preferring to be in the closed shape. From this explanation it can be seen that this

type of valve relies on a differential of pressure between input and output as the pressure at the

input must always be greater than the pressure at the output for it to work. Should the pressure at

the output, for any reason, rise above that of the input then the valve would open regardless of

the state of the solenoid and pilot valve.

In some solenoid valves the solenoid acts directly on the main valve. Others use a small,

complete solenoid valve, known as a pilot, to actuate a larger valve. While the second type is

actually a solenoid valve combined with a pneumatically actuated valve, they are sold and

packaged as a single unit referred to as a solenoid valve. Piloted valves require much less power

to control, but they are noticeably slower. Piloted solenoids usually need full power at all times

to open and stay open, where a direct acting solenoid may only need full power for a short period

of time to open it, and only low power to hold it.

Types

Many variations are possible on the basic, one way, one solenoid valve described above:

one or two solenoid valves;

direct current oralternating currentpowered;

different number of ways and positions;
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Common uses

Solenoid valves are used in fluid power pneumatic and hydraulic systems, to control

cylinders, fluid power motors or larger industrial valves. Automatic irrigation sprinkler systems

also use solenoid valves with an automatic controller. Domestic washing machines and dish

washers use solenoid valves to control water entry into the machine. Solenoid valves are used in

dentist chairs to control air and water flow. In the paintball industry, solenoid valves are usually

referred to simply as "solenoids. They are commonly used to control a larger valve used to

control the propellant (usually compressed air or CO2).Besides controlling the flow of air and

fluids, solenoids are used in pharmacology experiments, especially for patch-clamp, which can

control the application of against or antagonist.

Pneumatic cylinder:

Pneumatic cylinders(sometimes known as air cylinders) aremechanical devices which

use the power of compressed gas to produce a force in a reciprocating linear motion.

Likehydraulic cylinders,pneumatic cylinders use the stored potential energy of a fluid,

in this case compressed air, and convert it into kinetic energy as the air expands in an attempt to

reach atmospheric pressure. This air expansion forces a piston to move in the desired direction.

The piston is a disc or cylinder, and the piston rod transfers the force it develops to the object to

be moved. Engineers prefer to use pneumatics sometime because they are quieter, cleaner, and

do not require large amounts of space for fluid storage.

Because the operating fluid is a gas, leakage from a pneumatic cylinder will not drip out

and contaminate the surroundings, making pneumatics more desirable where cleanliness is a
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requirement. For example, in the mechanical puppets of the Disney Tiki Room,pneumatics are

used to prevent fluid from dripping onto people below the puppets.

Although pneumatic cylinders will vary in appearance, size and function, they generally

fall into one of the specific categories shown below. However there are also numerous other

types of pneumatic cylinder available, many of which are designed to fulfill specific and

specialized functions.

Types of Pneumatic Cylinders:

i) Single-acting cylinder

Single-acting cylinders (SAC) use the pressure imparted by compressed air to create a

driving force in one direction (usually out), and a spring to return to the "home" position. More

often than not, this type of cylinder has limited extension due to the space the compressed spring

takes up. Another downside to SACs is that part of the force produced by the cylinder is lost as it

tries to push against the spring. Because of those factors, single acting cylinders are

recommended for applications that require no more than 100mm of stroke length.
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ii) Double-acting cylinders

Double-acting cylinders use the force of air to move in both extend and retract strokes.

They have two ports to allow air in, one for outstroke and one for in stroke. Stroke length for this

design is not limited, however, the piston rod is more vulnerable to buckling and bending.

Addition calculations should be performed as well.

iii) Multi-stage, telescoping cylinders

Telescoping cylinders, also known as telescopic cylinders can be either single or double-

acting. The telescoping cylinder incorporates a piston rod nested within a series of hollow stages

of increasing diameter. Upon actuation, the piston rod and each succeeding stage "telescopes"

out as a segmented piston. The main benefit of this design is the allowance for a notably longer

stroke than would be achieved with a single-stage cylinder of the same collapsed (retracted)

length. One cited drawback to telescoping cylinders is the increased potential for piston flexion

due to the segmented piston design. Consequently, telescoping cylinders are primarily utilized in

applications where the piston bears minimal side loading.

iv) Rodless cylinders

Some rodless types have a slot in the wall of the cylinder that is closed off for much of its

length by two flexible metal sealing bands. The inner one prevents air from escaping, while the

outer one protects the slot and inner band. The piston is actually a pair of them, part of a

comparatively long assembly. They seal to the bore and inner band at both ends of the assembly.

Between the individual pistons, however, are camming surfaces that "peel off" the bands as the

whole sliding assembly moves toward the sealed volume, and "replace" them as the assembly

moves away from the other end. Between the camming surfaces is part of the moving assembly


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that protrudes through the slot to move the load. Of course, this means that the region where the

sealing bands are not in contact is at atmospheric pressure.

Depending on the job specification, there are multiple forms of body constructions available:

Tie rod cylinders: The most common cylinder constructions that can be used in many

types of loads. Has been proven to be the safest form.

Flanged-type cylinders: Fixed flanges are added to the ends of cylinder, however, this

form of construction is more common in hydraulic cylinder construction.

One-piece welded cylinders: Ends are welded or crimped to the tube, this form is

inexpensive but makes the cylinder non-serviceable.

Threaded end cylinders: Ends are screwed onto the tube body. The reduction of material

can weaken the tube and may introduce thread concentricity problems to the system.

Upon job specification, the material may be chosen. Material range from nickel-plated

brass to aluminum, and even steel and stainless steel. Depending on the level of loads, humidity,

temperature, and stroke lengths specified, the appropriate material may be selected.


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Gauge Pressure

Gauge pressure is zero-referenced against ambient air pressure, so it is equal to

absolute pressure minus atmospheric pressure. Negative signs are usually omitted.

Atmospheric Pressure

Atmospheric pressure is the force per unit area exerted into a surface by the weight

of air above that surface in the atmosphere of Earth (or that of another planet). In most

circumstances atmospheric pressure is closely approximated by the hydrostatic pressure caused

by themass ofair above the measurement point. Low-pressure areas have less atmospheric mass

above their location, whereas high-pressure areas have more atmospheric mass above their

location.

Mechanical model:

Mechanical Models offers a line of kits that provide everything you need to build an

attractive model using your mini lathe or mini mill. Our products include two cannons and four

Stirling cycle heat engines. The model engines are fully functional. Our kits are available in three

forms: material kits (material and drawings), assembly kits (fully machined parts ready for

assembly), and fully assembled models.

Hydraulic jack:

Hydraulic jacks are typically used for shop work, rather than as an emergency jack to be

carried with the vehicle. Use of jacks not designed for a specific vehicle requires more than the

usual care in selecting ground conditions, the jacking point on the vehicle, and to ensure stability

when the jack is extended. Hydraulic jacks are often used to liftelevators in low and medium rise

buildings. A hydraulic jack uses a fluid, which is incompressible, that is forced into a cylinder by
http://en.wikipedia.org/wiki/Atmosphere_of_Earthhttp://en.wikipedia.org/wiki/Fluid_pressurehttp://en.wikipedia.org/wiki/Masshttp://en.wikipedia.org/wiki/Earth%27s_atmospherehttp://en.wikipedia.org/wiki/Elevatorhttp://en.wikipedia.org/wiki/Elevatorhttp://en.wikipedia.org/wiki/Earth%27s_atmospherehttp://en.wikipedia.org/wiki/Masshttp://en.wikipedia.org/wiki/Fluid_pressurehttp://en.wikipedia.org/wiki/Atmosphere_of_Earth


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a pump plunger. Oil is used since it is self lubricating and stable. When the plunger pulls back, it

draws oil out of the reservoir through a suction check valve into the pump chamber. When the

plunger moves forward, it pushes the oil through a discharge check valve into the cylinder. The

suction valve ball is within the chamber and opens with each draw of the plunger. The discharge

valve ball is outside the chamber and opens when the oil is pushed into the cylinder. At this point

the suction ball within the chamber is forced shut and oil pressure builds in the cylinder.

In a bottle jackthe piston is vertical and directly supports a bearing pad that contacts the

object being lifted. With a single action piston the lift is somewhat less than twice the collapsed

height of the jack, making it suitable only for vehicles with a relatively high clearance. For lifting

structures such as houses the hydraulic interconnection of multiple vertical jacks through valves

enables the even distribution of forces while enabling close control of the lift.

In a floor jack (aka 'trolley jack') a horizontal piston pushes on the short end of a

bellcrank,with the long arm providing the vertical motion to a lifting pad, kept horizontal with a

horizontal linkage. Floor jacks usually include castors and wheels, allowing compensation for the

arc taken by the lifting pad. This mechanism provides a low profile when collapsed, for easy

maneuvering underneath the vehicle, while allowing considerable extension.
http://en.wikipedia.org/wiki/Bellcrankhttp://en.wikipedia.org/wiki/Bellcrank


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CHAPTER 4

BASIC CALCULATIONSHYDRAULIC MACHINERY

Hydraulic power is defined as flow times pressure. The hydraulic power supplied by a

pump:

Power = (P x Q) 600

where power is in kilowatts [kW], P pressure in bars, and Q is the flow in liters per

minute. For example, a pump delivers 180 lit/min and the pressure equals 250 bar, therefore the

power of the pump is 75 kW.

When calculating the power input to the pump, the total pump efficiency totalmust be

included. This efficiency is the product of volumetric efficiency, vol and the hydromechanical

efficiency, hm. Power input = Power output total. The average for axial piston pumps, total=

0.87. In the example the power source, for example a diesel engine or an electric motor, must be

capable of delivering at least 75 0.87 = 86 [kW]. The hydraulic motors and cylinders that the

pump supplies with hydraulic power also have efficiencies and the total system efficiency

(without including the pressure drop in the hydraulic pipes and valves) will end up at approx.

0.75. Cylinders normally have a total efficiency around 0.95 while hydraulic axial piston motors

0.87, the same as the pump. In general the power loss in a hydraulic energy transmission is thus

around 25% or more at ideal viscosity range 25-35 [cSt].


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Calculation of the required max. power output for the diesel engine, rough estimation:

(1) Check the max. powerpoint, i.e. the point where pressure times flow reach the max.

value.

(2)Ediesel= (PmaxQtot).

Qtot= calculate with the theoretical pump flow for the consumers not including leakages

at max. power point.

Pmax= actual pump pressure at max. power point.

Note:is the total efficiency = (output mechanical power input mechanical power). For rough

estimations, = 0.75. Add 10-20% (depends on the application) to this power value.

(3) Calculate the required pumpdisplacement from required max. sum of flow for the

consumers in worst case and the diesel engine rpm in this point. The max. flow can differ from

the flow used for calculation of the diesel engine power. Pump volumetric efficiency average,

piston pumps: vol= 0.93.

Pumpdisplacement Vpump= Qtot ndiesel 0.93.

(4) Calculation of prel. cooler capacity: Heat dissipation from hydraulic oil tanks, valves,

pipes and hydraulic components is less than a few percent in standard mobile equipment and the

cooler capacity must include some margins. Minimum cooler capacity,Ecooler= 0.25Ediesel


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At least 25% of the input power must be dissipated by the cooler when peak power is

utilized for long periods. In normal case however, the peak power is used for only short periods,

thus the actual cooler capacity required might be considerably less. The oil volume in the

hydraulic tank is also acting as a heat accumulator when peak power is used. The system

efficiency is very much dependent on the type of hydraulic work tool equipment, the hydraulic

pumps and motors used and power input to the hydraulics may vary a lot. Each circuit must be

evaluated and the load cycle estimated. New or modified systems must always be tested in

practical work, covering all possible load cycles.

An easy way of measuring the actual average power loss in the system is to equip the

machine with a test cooler and measure the oil temperature at cooler inlet, oil temperature at

cooler outlet and the oil flow through the cooler, when the machine is in normal operating mode.

From these figures the test cooler power dissipation can be calculated and this is equal to the

power loss when temperatures are stabilized. From this test the actual required cooler can be

calculated to reach specified oil temperature in the oil tank. One problem can be to assemble the

measuring equipment inline, especially the oil flow meter.


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CHAPTER 5

WORKING PRINCIPLE

The working of the process is fully pneumatic and hydraulic operated where the air is

working medium. In this unit compressor is used to supply the compressed air at certain

pressure. This pressurized air is passed to the solenoid valve. The solenoid valve is controlled by

control unit. This solenoid valve is used to control the direction of flow of air to the pneumatic

cylinder. In this pneumatic cylinder the piston rod actuates due to the pressure.

At the end of piston rod bending tool is attached. So that tool bends the rod into required v

shape. Thus the work piece clamped on the frame is bending due to the reciprocating motion of

the bend.


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For Example:

Hydraulic machines are part of our everyday lives. While going to school on a bus, both

the steering and the brakes use a hydraulic system. Or if we use an elevator at work, we make

making use of a hydraulic system.

Hydraulic machines use the power of fluid to do work. They are so popular because of

power can be transferred through the fluid in small tubes. Some hydraulic machines use a set of

pistons, which are devices that slide in a cylinder.

The pistons are connected by hoses filed with oil. Force is applied to one piston, known

as the "Master" piston. The force travels through oil in the hose and pushes up the second

"Slave" piston. The larger the "Slave" piston, the greater the force that's needed to push it up.

WORKING PROCESS OF HYDRAULIC MACHINE

A piece of hydraulic machinery uses a liquid (usually an oil) under pressure to transmit

energy. Lets consider a simple system such as the one that operates the clutch on my car. There

are two cylinders with a piston in each and a small tube running between them.

When stepping on the clutch pedal, force the piston on one of the cylinders (known as the

master cylinder) deeper into the cylinder pushing fluid under pressure into the other cylinder.

The fluid exerts pressure on the other cylinder (the slave cylinder) and develops a force which

pushes on the clutch.


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The relationship between force and pressure is:

Force = Area x Pressure

Which can be rearranged with algebra to

Pressure = Force / Area

This, by this is way, is why we measure pressure as in units such as pounds (force) per

square inch (area).

If we make the master cylinder smaller than the slave cylinder, say 1 square inch and 2

square inches respectively, and assume that the pressures are equal, we find that

Master cylinder force = 1/2 Slave cylinder force

So we have to apply half as much force to the master cylinder (at the pedal) as we want

from the slave cylinder (the clutch) and I don't have to put as much force on the pedal to operate

the clutch. The force amplification is very similar to a lever (such as a pair of plyers) but has the

added benefit that the master and slave cylinders can be located anywhere. The tube has many

twists and turns, each one of which would require joints if a mechanical system were used. Like

a lever, and I must move the master cylinder twice as far at the slave cylinder travels.

Brakes in the car operate similarly, but the tube coming from the master cylinder(s) are

branched into several pistons at the wheels. Flexible tubing is used so that the wheels can move

freely when the car goes over bumps.


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Machines such as backhoes and bulldozers use similar principles. However, in this case,

the fluid is kept at constant pressure continually by a pump connected to the engine and sent to

the slave cylinders when the operator opens a valve. This allows very large forces to be

developed at the slave cylinder.

Pneumatic systems are similar to hydraulics, by use gases (typically air) rather than

liquid. Since gas can be compressed considerable, a lot of air can be forced into a tank and the

energy used later. This make pneumatics suitable for systems where large forces and speed are

required at the same type such as jackhammers, nail guns, or paintball guns.

BASIC IDEA BEHIND HYDRAULIC SYSTEM

The basic idea behind any hydraulic system is very simple: Force that is applied at one

point is transmitted to another point using an incompressible fluid. The fluid is almost

always an oil of some sort. The force is almost always multiplied in the process. The picture

below shows the simplest possible hydraulic system:


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A Simple hydraulic system consisting of two pistons and an oil-filled pipe connecting

them. Click on the red arrow to see the animation.

In this drawing, two pistons (red) fit into two glass cylinders filled with oil (light blue)

and connected to one another with an oil-filled pipe. If you apply a downward force to one piston

(the left one in this drawing), then the force is transmitted to the second piston through the oil in

the pipe. Since oil is incompressible, the efficiency is very good -- almost all of the applied force

appears at the second piston.

The great thing about hydraulic systems is that the pipe connecting the two cylinders can

be any length and shape, allowing it to snake through all sorts of things separating the two

pistons. The pipe can also fork, so that one master cylinder can drive more than one slave

cylinder if desired. The neat thing about hydraulic systems is that it is very easy to add force

multiplication (or division) to the system.


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Hydraulic multiplication:

The piston on the right has a surface area nine times greater than the piston on the left.

When force is applied to the left piston, it will move nine units for every one unit that the right

piston moves, and the force is multiplied by nine on the right-hand piston. Click the red arrow to

see the animation.

To determine the multiplication factor,start by looking at the size of the pistons. Assume

that the piston on the left is 2 inches in diameter (1-inch radius), while the piston on the right is 6

inches in diameter (3-inch radius). The area of the two pistons is Pi * r2. The area of the left

piston is therefore 3.14, while the area of the piston on the right is 28.26. The piston on the right

is 9 times larger than the piston on the left.

Any force applied to the left-hand piston will appear 9 times greater on the right-hand

piston. So if you apply a 100-pound downward force to the left piston, a 900-pound upward force

will appear on the right. The only catch is that you will have to depress the left piston 9 inches to

raise the right piston 1 inch.

The brakes in your car are a good example of a basic piston-driven hydraulic system.

When you depress the brake pedal in your car, it is pushing on the piston in the brake's master

cylinder.Four slave pistons, one at each wheel, actuate to press the brake pads against the brake

rotor to stop the car.
http://auto.howstuffworks.com/auto-parts/brakes/brake-types/brake.htmhttp://auto.howstuffworks.com/auto-parts/brakes/brake-types/master-brake.htmhttp://auto.howstuffworks.com/auto-parts/brakes/brake-types/master-brake.htmhttp://auto.howstuffworks.com/auto-parts/brakes/brake-types/master-brake.htmhttp://auto.howstuffworks.com/auto-parts/brakes/brake-types/master-brake.htmhttp://auto.howstuffworks.com/auto-parts/brakes/brake-types/brake.htm


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Sample instructions for hydraulic bending machine operation:

1. Clamp the bending machine to a flat work surface so that it is upright and secure.

2.

Rotate the upper, short handle to a position above the bender.

3. Open the latch to make way for insertion of the tube. Insert the tube into the tube

groove.

4. Close the latch around the tube to hold it in place. Lower the upper, short handle

until the roll dies rest against the tube and the angle-measure is aligned at zero

degrees. Close the latch firmly to clamp down tightly on the tube.

5. Press the upper, short handle down until the zero on the roll-support aligns with

the desired bend degree on the angle-measure.

6. Rotate the upper, short handle upward to release the newly bent tube.

7. Connect the hydraulic bending machine to an air compressor or hydraulic pump.

Pull back the brass coupling ring on the compressor or pump's hose and slide it

onto the machine's connector. Release the ring to secure the connection.

8. Set the machine's groove to receive the diameter of pipe for bending. Do this by

moving the machine's pin to the appropriate setting.

9. Slide the pipe into the machine's groove so that the point of the intended bend

rests atop the zero point of the angle-measure.

10.Turn on the compressor or pump.

11.Unlock the machine's safety lock and allow the machine to move and bend the

pipe until the indicator on the angle-measure reaches the desired degree of bend.

12.Close the safety lock on the bender to stop the bending process. Turn off the

compressor or pump.


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CHAPTER 6

APPLICATIONS AND ITS ADVANTAGES

APPLICATION AREAS

Furniture industry

Chemical and boiler plants

Automobile and automotive component supplier industries

Agriculture

Moulded luggage manufacturers

Machines are well-known in the market due to their dimensional accuracy, high

tensile strength, corrosion resistance, compact design, simple operations and high reliability.

Applicable for bending pipes and other material in different angels, these are available in

different finishes and specifications. Clients can avail these machines at industry leading

prices.

Bending Machines are used to bend metal pipe and tubing. Different bending

machines exist to handle each of these two different types of metal conduit. Hand-held

machines clamp to a work surface for stability and bend thin metal tubing. Larger, heavy-

duty hydraulic machines connect to air pumps to increase torque and bend thick metal pipe.

Each machine usually comes equipped with an angle-measure to ensure the proper degree of

bend. Identify whether tubing or pipe needs bending, and chose the appropriate bending

machine for the job.


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ADVANTAGES

Machining time reduced

Quick response

Simple in construction easy to maintain and repair.

Cost of the unit is less when compared to other systems.

Comparatively the operation cost is less

Continuous operation is possible without stopping.

5000 kg push force, makes possible bending of heavy sections possible

Ease of operation

Gradual application of force prevents the pipe damage.

Quick release of the ram using relief valve makes operation fast.

Ease of maintenance.


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CHAPTER 7

CONCLUSION

Thus the unit compressor is used to supply the compressed air at certain pressure. This

pressurized air is passed to the solenoid valve. The solenoid valve is controlled by control unit.

This solenoid valve is used to control the direction of flow of air to the pneumatic cylinder. In

this pneumatic cylinder the piston rod actuates due to the pressure. Hydraulic Pumps are used in

V-type Bending machine which has a power density about ten times greater than an electric

motor (by volume). They are powered by an electric motor or an engine, connected through

gears, belts, or a flexibleelastomeric coupling to reduce vibration.

And then the popularity of hydraulic machinery is due to the very large amount of power

that can be transferred through small tubes and flexible hoses, and the high power density and

wide array ofactuators that can make use of this power. Hydraulic machinery is operated by the

use of hydraulics, where a liquid is the powering medium.
http://en.wikipedia.org/wiki/Power_densityhttp://en.wikipedia.org/wiki/Elastomerhttp://en.wikipedia.org/wiki/Actuatorhttp://en.wikipedia.org/wiki/Actuatorhttp://en.wikipedia.org/wiki/Elastomerhttp://en.wikipedia.org/wiki/Power_density


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BIBLIOGRAPHY

Todd, Robert H.; Allen, Dell K.; Alting, Leo (1994), Manufacturing Processes Reference

Guide(1st ed.), Industrial Press Inc.,ISBN0-8311-3049-0.

Pipe Bending Methods,retrieved 2009-02-01.

Mentella, A.; Strano, M. (10 October 2011). "Rotary draw bending of small diameter

copper tubes: predicting the quality of the cross-section".Proceedings of the Institution of

Mechanical Engineers, Part B: Journal of Engineering Manufacture226 (2): 267278.

doi:10.1177/0954405411416306.

Strano, Matteo; B.M. Colosimo, E. Del Castillo (2011)."Improved design of a three roll

tube bending process under geometrical uncertainties".Esaform. AIP Conf. Proc. 135

hydrolic pipe bending machine

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