Plc Programmable Logic Controller

AUTOMATIC temper OF hydraulic SYSTEM USING PLC * Comp any Products & Services * Abstract * Hydraulic governing body * Bow Compression Machine * Circuit Diag swot up * Description * h disperse-raiser Unit * Solenoid valve * Introduction To PLC * Softw atomic compute 18 * Advantages Of PLC * Introduction To PLC * Existing dodge of rules of rules * Proposed System * Ladder logical system Diagram * Ladder Logic Description * aught Saving Calculation * For Existing Method * For Proposed Method * Advantages & Applications * Conclusion * References mo custom One of the ch e genuinely(prenominal)enging factor in factories, for the proper agencying of the auto for the long duration with efficiency is to keep certain parameters wi keen a specific range. Thus, in this paper, we befuddle knowing a course plot for roamning PLC with the objective to automatic every(prenominal)y function the hydraulic system. Our main want is to design a PLC which crumb be drawed to hydraulic s ystem to implement the parameters and transactions like Temperature spying, Pressure catching, Lubrication, Automatic political form surgical process and rock inunct level detection.The mentioned parameters and actions stooge be perceive and operated finished PLC without any manual of arms checking and action. This saves more origin to industries by diminution the index piece utilization. INTRODUCTION In the last decades, the machines employ in the industries were operated manually. So tutelage its certain im appearanceant parameters in a specific range was difficult. too they furthert joint not be analyze out frequently. This results in uncomely functioning of the machine. Also, the machines usher outnot work efficiently for a long measure.For example, if the temperature of the anoint goes beyond the desired measure out it go away affect the machine function. Hence the machine accessories keepnot withstand this high temperature. This leads to the dam age in machine and the durability of the machine likewise gets reduced. Thus, the working machine requires frequent checking of certain parameters to maintain the appraise within the contract range for proper work. The various parameters to be checked frequently argon 1. Temperature detection 2. Lubrication 3. Automatic machine operation 4. crude rock oil level detection . Pressure Thus we atomic number 18 using a PLC to dictation all these parameters. We argon designing a melt nap draw to tally all the parameters automatically. In this paper, we argon describing about the hydraulic pay back system in which PLC is theatrical roled to control its working. An introduction of PLC is provided and likewise the ladder diagram overview. We will be discussing about the advantages of PLC and also the provide prudence estimation in the industries by using PLC. The machine which we have taken under con inc channelration for implementation is BOW CORRECTION mold.Also, the ch iller whole is described as it plays a major role for the power rescue purpose. HYDRAULIC DRIVE SYSTEM Ahydraulic hinge upon systemis a drive ortransmissionsystem that aims pressurizedhydraulic unsoundto drivehydraulic machinery. The term hydrostatic refers to the transfer of energy from t devastation and gouge, not from thekinetic energyof the f offset gear. Principle of a hydraulic drive Pascals lawis the basis of hydraulic drive systems. As the stuff in the system is the same, the impression that the fluid gives to the meets is at that placefore able to compact ? rea. In such a way, a blue speculator feels a itty- numberty force and a banging plunger feels a large force. For an understanding of how a hydraulic system plant, we must k without delay the rudimentary tenets, or laws, of hydraulics, that is, of confined liquefiables under wring sensation. This will be made easier, however, if we archetypal examine the somewhat simpler laws governing the deme anour of liquefiables whenunimprisoned, that is, in open containers. 1. Liquids in open containers. a. Density and specific sedateness. The initiative characteristic of an unconfined crystalline which interests us is its density.The density of a fluid is the puket over of a social whole of measurement volume of it. The whole of volume normally apply in this text is the cubic foot the unit of weight normally employ is the pound. The measurement of density, to which the densities of all some other liquids ar referred, is that of pure irrigate at zipper degrees centigrade (32 degrees Fahrenheit), and at sea-level atmospheric pressure. b. cram and pressure. A liquid has no shape of its own. It acquires the shape of its container up to the level to which it fills the container. However, we know that liquids have weight.This weight exerts a force upon all sides of the container, and this force can be measured. thereof, for unconfined liquids, that is, liquids in open cont ainers, the pressure in pounds per public squ ar inch exerted by the liquid on the bottom of the container is peer to the weight of the liquid on distributively squargon inch of the bottom of the container. It must be show that theweightof the liquid is here thought of as aforceexerted on the bottom of the container. Expressed as a formula, we have Pressure = effect per unit araIt is understood that the word pressure, when not otherwise qualified, substancepressure in pounds per square inch. This is called the total force and is obtained by the formula list Force = Pressure X Area The pressure exerted by a liquid on the bottom of a container is independent of the shape of the container, and depends and on the height and density of the liquid. 2. Liquids in enclosed systems. a. Liquids are overmuch incompressible. The following both basic principles will help to explain the behavior of liquids when enclosed a) Liquids are practically incompressible. ) The applied pressure is transmitted as in all directions at once. b. Increase of force with area. The ratio betwixt theforce applied to the littler pistonand theforce applied to the big pistonis the same as the ratio between thearea of the littler pistonand thearea of the larger piston. Expressed as a proportion, thuslyce, we have Force on larger piston/Force on smaller piston = Area of larger piston/Area of smaller piston This means that the mechanical advantage obtainable by such an arrangement is equal to the ratio between the areas of the dickens pistons.Since the area of the larger piston chamber is 10 times as great as that of the smaller cylinder, pushing the smaller piston put downwards a distance of 1 inch will act as the larger piston upward scarcely 1/10 of an inch. The ratio between the displacement of liquid in the smaller cylinder and the displacement of liquid in the larger cylinder is once once more equal to the ratio between their areas. so that the amount of work (force X di stance) done by the larger piston is exactly the same as the amount done by the smaller piston. c. Multiple units.It is not requisite to confine our system to a single course from the source of hydraulic power. Hydraulic power whitethorn be transmitted in some(prenominal) directions to do multiple jobs. PUMP In practice we usually get hold of some guile which will deliver, over a period of time, a definite volume of fluid at the required pressure, and which will hatch to deliver it as long as we desire it to do so. much(prenominal) a device is called a eye. Basic principles of warmnesss. A hydraulic pump is a mechanical device which forcibly moves, or displaces, fluids.Various pumping principles are sedulous in the different types of hydraulic pumps, only one fundamental principle applies to all a volume of fluid entering the intake opening, or port, is moved by mechanical action and forced out the sort out port. Hydraulic fluids. Al close to any free-flowing liquid is s uitable as a hydraulic fluid, as long as it will not chemically injure the hydraulic equipment. For example, an acid, although free-flowing, would obviously be unsuitable because it would corrode the gold parts of the system. a. Basic units of a hydraulic system. 1.A reservoir, or supply tank car, containing vegetable oil which is supplied to the system as destinyed and into which the oil from the return line flows. 2. A pump, which supplies the necessary working pressure. 3. A hydraulic cylinder, or actuating cylinder, which uses the hydraulic energy developed in the pump to move the door. 4. A cut-out valve, by means of which the pressure in the actuating cylinder may be maintained or released as desired. 5. A check valve, rigid in the return line to permit fluid to move in unaccompanied one direction. 6. Hydraulic lines, such as piping or hose, to connect the units to each other.The supply tank must have a aptitude large enough to keep the entire system filled with oil an d furnish additional oil to make hot the inevitable losses from leakage. The tank is vented to the atmosphere thus atmospheric pressure (14. 7 pounds per square inch) forces the oil into the inlet, or suction, side of the pump. The tank is generally placed at a higher(prenominal) level than the other units in the system, so that gravity assists in feeding oil into other units. The pump is the hand-operated, reciprocating piston type. SOLENOID VALVE Asolenoid valveis anelectromechanicallyoperatedvalve.The valve is controlled by anelectric current done asolenoid in the field of study of a twain-port valve the flow is switched on or off in the wooing of a three-port valve, the outflow is switched between the deuce outlet ports. Multiple solenoid valves can be placed together on amanifold. Solenoid valves are the most frequently use control elements influidics. Their tasks are to shut off, release, dose, consider or mix fluids. They are found in numerous performance areas. Sole noids offer debauched and safe switching, high reliability, long service life, good medium compatibility of the materials apply, low control power and compact design.There are many valve design variations. Ordinary valve can have many ports and fluid paths. A 2-way valve, for example, has 2 ports if the valve isclosed, wherefore the two ports are attached and fluid may flow between the ports if the valve isopen, past ports are isolated. If the valve is open when the solenoid is not energized, then the valve is termednormally open(N. O. ). Similarly, if the valve is closed when the solenoid is not energized, then the valve is termednormally closed. 1There are also 3-way and more complicated designs.A 3-way valve has 3 ports it connects one port to either of the two other ports ( truely a supply port and an exhaust port). Solenoid valve are also characterized by how they operate. A small solenoid can show a limited force. If that force is sufficient to open and close the valve, then adirect actingsolenoid valve is possible. An gravelly relationship between the required solenoid forceFs, the fluid pressureP, and the opening areaAfor a direct acting solenoid value is Wheredis the orifice diameter. A typical solenoid force might be 15N (3. lbf). An application might be a low pressure (e. g. , 10 pounds per square inch (69kPa)) gas with a small orifice diameter (e. g. ,3? 8in (9. 5mm) for an orifice area of 0. 11sqin (7. 1? 10? 5m2) and approximate force of 1. 1lbf (4. 9N)). When high pressures and large orifices are encountered, then high forces are required. To generate those forces, aninternally pilotedsolenoid valve design may be possible. 1In such a design, the line pressure is utilise to generate the high valve forces a small solenoid controls how the line pressure is use.Internally piloted valves are used in dishwashers and irrigation systems where the fluid is water, the pressure might be 80 pounds per square inch (550kPa) and the orifice diameter might be3? 4in (19mm). In some solenoid valves the solenoid acts directly on the main valve. Others use a small, fare solenoid valve, known as a pilot, to actuate a larger valve. While the second type is actually a solenoid valve combine 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 decompresser. Piloted solenoids usually need ripe power at all times to open and cohere 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. A direct acting solenoid valve typically operates in 5 to 10 milliseconds. The operation time of a piloted valve depends on its size typical value are 15 to 150 milliseconds. Solenoid valves are used influid powerpneumatic and hydraulic systems, to control cylinders, fluid power motors or larger industrial valves.Automaticirrigation sprinklersy stems also use solenoid valves with an automaticcontroller. Domesticwashing machinesanddishwashersuse solenoid valves to control water gateway into the machine. Solenoid valves are used indentist chairsto control air and water flow. In thepaintballindustry, solenoid valves are usually referred to simply as solenoids. They are unremarkably used to control a larger valve used to control the propellant (usually compressed air or CO2). In addition to this, these valves are now been used in household water purifiers (RO systems).Besides controlling the flow of air and fluids, solenoids are used in pharmacology experiments, especially for patch-clamp, which can control the application of agonist or antagonist. Many variations are possible on the basic, one-way, one-solenoid valve described above * one- or two-solenoid valves * direct currentor jump currentpowered * different number of ways and positions INTRODUCTION TO PLC AProgrammable Logic concealler, or PLC, is more or less a sma ll ready reckoner with a build-in operating system (OS). This OS is exceedingly specialized to handle incoming events in real time, i. . at the time of their occurrence. The PLC has infix lines where sensors are connected to notify upon events (e. g. temperature above/below a certain level, liquid level reached, and so on ), and takings lines to signal any reaction to the incoming events (e. g. start an engine, open/close a valve, and so on ). The system is substance abuser classmable. It uses a language called Relay Ladder or RLL (Relay Ladder Logic). The name of this language implies that the control system of logic of the earlier days, which was make from relays, is being simulated.The PLC is primarily used to control machinery. A computer program is indite for the PLC which turns on and off payoffs based on input narrows and the internal program. In this aspect, a PLC is similar to a computer. However, a PLC is designed to be programmed once, and run repeatedly a s needed. In fact, a crafty programmer could use a PLC to control not only simple devices such as a garage door opener, but their whole house, including switching lights on and off at certain times, monitoring a custom built security system, etc.Most commonly, a PLC is found inside of a machine in an industrial environment. A PLC can run an automatic machine for old age with little human intervention. They are designed to withstand most stinging environments. When the first electronic machine controls were designed, they used relays to control the machine logic (i. e. press Start to start the machine and press Stop to jibe the machine). A basic machine might need a circumvent covered in relays to control all of its functions. There are a a few(prenominal) limitations to this type of control. * Relays fail. * The delay when the relay turns on/off. There is an entire wall of relays to design/wire/troubleshoot. A PLC overcomes these limitations, it is a machine controlled operati on. PLCs are becoming more and more intelligent. In recent years PLCs have been integrated into electric communicationsnetworks i. e. , all the PLCs in an industrial environment have been plugged into a network which is usually hierarchically organized. The PLCs are then supervised by a control center. There live many proprietary types of networks. One type which is widely known isSCADA(Supervisory Control and Data Acquisition).The PLC is a purpose-built machine control computer designed to read digital and analog inputs from various sensors, execute a user defined logic program, and write the resulting digital and analog output values to various output elements like hydraulic and pneumatic actuators, indication lamps, solenoid coils, etc. Scan cycle Exact details vary between manufacturers, but most PLCs follow a scan-cycle format. Overhead Overhead includes testing I/O module integrity, verifying the user program logic hasnt smorgasbordd, that the computer itself hasnt locked u p (via a watchdog timer), and any necessary communications.Communications may include traffic over the PLC programmer port, remote I/O racks, and other external devices such as HMIs (Human Machine Interfaces). stimulus scan A snapshot of the digital and analog values present at the input tease is saved to an input reposition table. Logic execution The user program is scanned element by element, then staff by rundle until the end of the program, and resulting values written to an output memory table. Output scan set from the resulting output memory table are written to the output modules. erstwhile the output scan is complete the process repeats itself until the PLC is powered down.The time it takes to complete a scan cycle is, appropriately enough, the scan cycle time, and ranges from hundreds of milliseconds (on older PLCs, and/or PLCs with very complex programs) to only a few milliseconds on newer PLCs, and/or PLCs executing short, simple code. ADVANTAGES OF PLC * PLCs hav e flexibleness (i. e. ) it is possible to use just one model of PLC to run any one of the 15 machines. * In a PLC program circuit the PLC program can be used from any keyboard sequence in a matter of minute and rewriting is required. PLC has a large number of contacts for each coil in its programming. * Increased technology makes it possible to compact move functions into smaller and less expensive packages. * A PLC programmed circuit can be pre-un ad evaluated in the officer or lab. The program can be typed in tested observed and modified if needed. * PLC circuit operation can be seen during operation directly on a CRT screen. * The operation speed for the PLC program is very fast. * PLC is more reliable. * A PLC programmer who works in digital or Boolean control system can easily perform PLC programming. PLCs program cant be made unless the PLC properly unlocked and programmed. LADDER LOGIC draw What is a Ladder Diagram? A Ladder Diagram is one of the simplest systems used to p rogram a PLC. It is a graphical programming language evolved from electrical relay circuits. Each program statement is represented with a line, called the wheel spoke, that has all relevant inputs to the go forth and the output to the right. The output device of a go is energized if electric power can conceptually flow from the remaining side of the spoke to the right side.Input devices are assumed to block the flow of power if they are not activated. During the execution of a ladder diagram, the PLC reads the states of all inputs, then determines the states of all outputs showtime from the stave at the top side, going down to the last rung, and finally updates the state of the output devices. * Naming Convention During the victimisation of a PLC program, we must use specific names to chance upon the inputs, outputs, memory flags, timers and counters. PLC manufactures use a variety of approaches in naming the inputs, outputs and other resources.A typical naming convention i s to identify inputs with the letter I and outputs with the letter O, followed be a 1-digit number that identifies the slot number and a 2-digit number that identifies the position of the input or output in the slot. For example I100 refers to the first input of slot 1 O200 refers to the first output of slot 2. some manufactures number the inputs or outputs starting from 00, while others use the number 01 to identify the first input or output. It is also common to use amount like 400 e. t. c. The state of an output can be also used as an input in a ladder diagram.In such a case the PLC uses the state of the specific output device that is stored in the output image memory. * Relay Logic book of statements (XIC and XIO) Examine if closed (XIC) Use the XIC affirmation in your ladder program to determine if a point is On. When the culture is executed, if the bit address is on (1), then the instruction is evaluated as true. When the instruction is executed, if the bit address i s off (0), then the instruction is evaluated as false. Examine if Open (XIO) -/ Use the XIO instruction in your ladder program to determine if a bit is Off.When the instruction is executed, if the bit addressed is off (0), then the instruction is evaluated as true. When the instruction is executed, if the bit addressed is on (1), then the instruction is evaluated as false * Relay Logic instruction manual Input Transition Sensing Positive Transition spirit (PTS) The given of the right tie-up is ON for one ladder rung evaluation when a change from OFF to ON at the specified input is sensed. Negative Transition Sense (NTS) The condition of the right link is ON for one ladder rung evaluation when a change from ON to OFF at the specified input is sensed. * Output tuitions Output Energize (OTE) -( ) If the condition of the left link of the OTE is ON then the corresponding bit in the output data memory is set. The device wired to this output is also energized. Negative Output Energize (NOE) (/) If the condition of the left link of the OTE is OFF then the corresponding bit in the output data memory is set. The device wired output is also energized. Output hook/ get dressed (OTL) and Output Unlatch/Reset (OTU) If the condition of the left link of the OTL is momentary ON then the corresponding bit in the output data memory is set, and carcass set even if the condition switches to the OFF state.The output will remain set until the condition of the left link of the OTU is momentary ON * Basic Logic Functions (OR, AND) both Input OR Function The output is ON only if the two inputs are OFF. Two Input AND Function The output is ON if both of the two inputs are ON. * Basic Logic Functions (NAND,NOR) Two Input NAND Function The output is ON if any of the two inputs is OFF. Two Input NOR Function The output is ON if both of the two inputs are OFF. * Basic Logic Functions (EXOR, EXNOR) Two Input EXOR Function The output is ON if any of the two inputs is ON, but not both. Two Input EXNOR FunctionThe output is ON if both of the two inputs are either OFF or ON. * Set/Reset Latch Set/Reset Latch using a Hold-in contact Set/Reset Latch using Latch/Unlatch outputs Notes O100 means that the output is idempotent If both inputs are ON then normally the output is OFF, since the Unlatch rung appears last in the ladder diagram. * timepiece Instructions Timer Instructions are output instructions used to time intervals for which their rung conditions are true (TON), or false (TOF). These are software timers. Their resolution and verity depends on a tick timer maintained by the microprocessor.Each timer instruction has two values (integers) associated with it Accumulated apprise (ACC) This is the current number of ticks (time-base intervals) that have been counted from the moment that the timer has been energized. P define Value (PR) This is a determine value set by the programmer. When the lay in value is equal to, or greater than the preset value, a statu s bit is set. This bit can be used to control an output device. Each timer is associated with two status bits Timer alter piece of music (EN) This bit is set when the rung condition to the left of the timer instruction are true.When this bit is set, the accumulated value is incremented on each time-base interval, until it reaches the preset value. Done Bit (DN) This bit is set when the accumulated value is equal to the preset value. It is reset when the rung condition becomes false. * Timer On-Delay (TON) Instruction The TON instruction begins count when its input rung conditions are true. The accumulated value is reset when the input rung conditions become false. Timer ladder diagram example. Typical timing diagram (Assume that Preset = 07). * Timer Off-Delay (TOF) InstructionThe TOF instruction begins count when its input rung makes a true-to-false transition, and continues numerate for as long as the input rung remains false. The accumulated value is reset when the input rung conditions become false. Timer ladder diagram example. Typical timing diagram (Assume that Preset = 07). * tenacious Timer (RTO) Instruction The RTO instruction begins count when its input rung conditions are true. The accumulated value is retained when the input rung conditions become false, and continues numeration after the input rung conditions become true. * respond InstructionsCounter Instructions are output instructions used to count false-to-true rung transitions. These transitions are usually caused by events occurring at an input. These counters can be UP (incrementing) or ingest (decrementing). Each counter instruction has two values (integers) associated with it Accumulated Value (ACC) This is the current number of the counter. The initial value is zero. Preset Value (PR) This is a predetermined value set by the programmer. When the accumulated value is equal to, or greater than the preset value, a status bit is set. This bit can be used to control an output device.E ach counter is associated with two status bits Counter Enable Bit (EN) This bit is set when a false-to-true rung condition to the left of the counter instruction is discover. Done Bit (DN) This bit is set when the accumulated value is equal to the preset value. It is reset when the rung condition becomes false. The maximum count value is 9999*. After a maximum count is reached, the counters reset and start counting from zero. * Count-up (CTU) Instruction The CTU instruction increments its accumulated value on each false-to-true transition at its input, starting from 0. Counter ladder diagram example.Typical timing diagram (Assume that Preset = 10). * Count-down (CTD) Instruction The CTD instruction decrements its accumulated value on each false-to-true transition at its input, starting from 0. Counter ladder diagram example. Typical timing diagram (Assume that Preset = -10). * The Reset (RES) Instruction The RES instruction resets timing and counting instructions. When the RES inst ruction is enabled it resets the following. CountersAccumulated value, Counter Done Bit , Counter Enabled Bit. Timers Accumulated value, Timer Done Bit, Timer Timing Bit, Timer Enable Bit.Reset ladder diagram example. ADVANTAGES APPLICATION * Automatic control of machine. * Free from manual operation and frequent checking. * Machine fault is reduced. * Energy consumption is reduced. * This method can save more power. * Industrial application mainly used for boiler production. * Drilling and boring applications. * This applications can be implemented for all machines in BHEL. BOW CORRECTION automobile These are the specifications of the bow chastening machine currently in use. MACHINE BOW CORRECTION MACHINE CAPACITY 600 TONS CYLINDER BORE 550 MM RAM diam 520 MMDAYLIGHT 3000 MM THROAT 1700 MM STROKE euchre MM CONNECTED LOAD 60+1+5 HP TOTAL WEIGHT 80 TONS BOLSTER SIZE 1500* two hundred0*200 MM SPEEDS OF OPERATION 15mm/sec APPROACH6mm/sec PRESSING60mm/sec RETURN PURPOSE. In th e pipes used in boilers, small pipes are attached using weld. This welding makes the pipe to bent. Thus its surface becomes uneven and makes it imperfect to be used in boilers. In this case this machine is used. Using this machine the bents and bows can be straightened and makes the pipes perfect to be used in the boilers. CIRCUIT DIAGRAM OPERATION.The hydraulic circuit is designed to achieve fast approach speed, slow pressing speed and fast return speeds by use of a single pump. The fast approach speed is achieved by ensuring that the cylinder ram moves down finished its self weight or what is termed as gravity fall. To achieve gravity fall of the cylinder of the cylinder it is important to assure that at all times the pressure in return line is minimum 5 kg/ cm2. On starting the motor the pump delivery is directed to the tank through unloading type comforter valve no. 4. The same flow is directed to the Z1 lines of catridge valves 5 7, which ensures that the valves are closed .On operation of solenoid S1 of main relief valve the pump flow is directed to the catridge valves, however out-of-pocket to differential areas the catridges are still closed and pump reaches system pressure and unloads to tank through relief valve 4. On operation of solenoid S2( valve 6) along with S1, port A of solenoid valve no. 6 is connected to tank Y1 which facilitates opening of catridge valve 5 and hence the oil flows into the forward line of the cylinder resulting in downward movement. At the same time the oil in the return line of the cylinder is connected to tank at the set pressure through valve no. 11.Hence the cylinder moves down with slow pressing speed. On operation of solenoid S4 ( valve 8) along with S1 S2 the X port of catridge valve 10 is connected to tank through valve 8, 6 and port Y1 that ensures the opening of the catridge valve 10. Opening of the catridge valve ensures that the return line is connected directly to tank and hence the cylinder oves down wit h its self weight and fast approach speed is achieved. At the same time prefill valve 14 opens to fill the cylinder forward area with oil. To set the maximum fast approach speed valve 10 is provided with a stroke adjustment setting.On operation of solenoid S3(valve 6) along with S1, port B of solenoid valve no. 6 is connected to tank Y1 which facilitates opening of catridge valve 7 and hence oil flows into the return line of the cylinder. At the same time since A port of solenoid valve no. 6 is connected to pump port X4 is also connected to pump, ensures the opening of prefill valve no 14 and that the forward line of the cylinder is connected back to tank. This results in filch movement of the cylinder. Pressure relief valve 9 is provided to ensure smooth slowness of the cylinder from fast approach to pressing.The valve ensures that the pressure in X port of the cartridge valve does not exceed set pressure therby ensuring that the valve closes slowly reducing jerks. The hot oil fro m the machine is then sent to the chiller unit to reduce its temperature. CHILLER UNIT In the chiller unit, the refrigerant is used to cool down the hot oil from the machine. REFRIGERATION A liquid whose Saturation temperature at normal atmospheric pressure is below the temperature that is to be produced by refrigeration is chosen as the working liquid in the refrigerant.Such a liquid will evaporate at begin temperatures and will absorb hear as it does so. This heat is extracted from the surroundings. The vapour formed in this way is compressed in a compressor. After compression the refrigerant may be in the vapour state or, in the liquid state if its temperature after compression is not greater than the saturation temperature at that increase pressure. The low temperature vapour is condensed in a condenser, in doing so it lowers its temperature below the surroundings . Now the condensed liquid is expanded to a lower pressure and the cycle of refrigeration is repeated.REFRIGERATIO N CYCLE * Compressors are used in vapour compression cycles. It is the heart of the system and it sucks low-pressure refrigerant vapour from the evaporator and compresses it to a pressure corresponding to the saturation temperature that will be higher than continuously re-circulate the refrigerant through the system. * Air-cooled condensers are heat exchangers,which scorn heat from the condensing refrigerant to the atmosphere. * The function of condenser in a refrigerated system is to de-superheat and condense the compressed discharge refrigerant vapour.High-speed fans are mostly used to speed up the process. * At the exit of the condenser the refrigerant loses temperature but still is in high-pressure state. The temperature falls down a little high to the ambient. * Dryers are mainly used to witch the moisture content if any mixed with the refrigerant. When the refrigerant passes through its thin filter mesh the moisture gets trapped on the silica change and clean refrigerant fl ows through. * Throttle valve(also called as Expansion valve)is also a very important component of the vapour compression refrigeration system.The function of an expansion device is to expand the liquid refrigerant from the condensing pressure to the evaporating pressure. Also it throttles the required flow into the evaporator depending on the load conditions. Commonly used expansion devices are capillary tubes, thermostatic expansion valves and constant pressure expansion valves. * Any liquid when evaporate creates a cooling effect. same applies here, when the refrigerant exists expansion valve it is partly in vapour state at low temperature and pressure. It flows through the evaporator and exchanges heat with the surroundings. After existing the evaporator it has gained heat from the surrounding media, thus lowering the temperature in the freezing compartment. This superhead vapour passes further and is pinched by the compressor, which compresses it,and delivers to condenser, th us, completing the refrigeration cycle. The ladder diagram used in this machine is CNT_ON CNT_OFF MEM_1 MEM_1 MEM_1 MOT_ON MOT_ON MOT_OFF VAL4_ONVAL4_ON VAL4_ON MEM_2 MEM_2 S1 S2 S3 S4 S5 FAST_APP FAST_APP S1 S2 S3 S4 S5 PRESS_ON TIMER T1 PRESET 15 ACC 0 PRESS_ON S1 S2 S3 S4 S5 HOLD_ON HOLD_ON HOLD_MEM HOLD_MEM S1 S2 S3 S4 S5 RET_ONRET_ON VAL4_ON COMPARE TEMP_ON45 TEMP_ON MEM_4 MEM_4 CHILLER_ON TEMP_ON CHILLER_OFF COMPARE TEMP_ON45 LOW_SEN ALARM_ON V_LOW_SEN TANK_ONPRES_ON VAL14_ON EXISTING SYSTEM * There is no temperature detection system. Hence, the chiller unit has to function continuously irrespective of hydraulic oils temperature. * Possibilities of machine can run due to friction since there is no Indication of oil in tank. * The chiller unit is cut continuously hence there is a possibilities of lot of Energy consumption losses. * There is no automatic control for the whole machine. * There is no automatic function for declamping and lubrication. There is no oil lev el sensor in the hydraulic tank to sense the oil level in the tank. * Relays are used which is not automatic and inefficient. HORIZONTAL BORING MACHINE HYDRAULIC TANK CHILLER UNIT PUMP SOLENOID VALVE PROPOSED SYSTEM * In this method there is a temperature sensor which is used to sense the temperature of the oil in the hydraulic tank. * The chiller unit will be turned on only when the oil temperature gets increased with the specified value of oil temperature * Friction of the machine can be reduced by implementing the lubrication function. Oil level in the hydraulic tank can be detected by using an oil level sensor . * Two types of oil level sensor is used. I. Low level sensor II. Very low level sensor So that we can avoid the machine streamlet in dangerous condition. * All the operation in one axis (x or y or z) can be operated by a single push button switch. * Declamping and lubrication function takes place automatically. ENERGY bringing CALCULATION * WITH CHILLER UNIT WORKING CONTINUOUSLY For continuous lead of chiller unit the motor consumes 18KW. Per day morning -4hrs night -8hrs so chiller unit runs totally 12hrs a day. 8KW*12hrs=216 KWhr The chiller unit consumes 216KWhr per day. For electrical energy 1unit= Rs. 5 Therefore 216*5= 1080 So for 216 unit it cost Rs. 1080 per day. 1080*30=Rs. 32,400 For 1month it costs Rs. 32,400 32400*303= Rs. 98,17,200 For 1year it costs Rs. 98,17,200. * WITH PLC For automatic on/off of chiller unit the motor consumes 10KW. Per day morning -4hrs night -8hrs so chiller unit runs totally 12hrs a day. 10KW*12hrs=120KWhr The chiller unit consumes 120KWhr per day. For electricity 1unit= Rs. 5 Therefore 120*5= 600 So for 120unit it costs Rs. 600 per day. 600*30=Rs. 8,000 For 1month it costs Rs. 18,000 18000*303= Rs. 54,54,000 For 1year it costs Rs. 54,54,000. CONCLUSION This project mainly focuses the oil temperature and oil level detection and also the automatic control of machine. Implementation of this project is simple and very economical. This applications can be implemented for all machines in BHEL. All the functions can be achieved through a single PLC program. The advantage of our project is used to eliminate manual checking and operation. The above mentioned parameters and operation can be sensed and operated through PLC.This project saves more power to industries by reducing the power consumption. REFERENCES 1. Allen bradely Instruction Set user manual by Rockwell Automation. 2. Programmable Logic Controllers programming Methods and Applications by John R. Hackworth and Frederick D. Hackworth, Jr 3. Ladder logic fundamentals industrial control system fall 2006. 4. DOE FUNDAMENTALS HANDBOOK INSTRUMENTATION AND CONTROL Volume 2 of 2- U. S. Department of Energy Washington, D. C. 20585. 5. Automating Manufacturing Systems with PLCs (Version 5. 0, May 4, 2007) -Hugh doodly-squat