Diesels type Ch 36/45 are stationary, four-stroke with jet spraying of fuel. These diesel engines are available in four-cylinder (4Ch 36/45 (G-60)) and six-cylinder (6Ch 36/45) versions. These diesel engines are designed to drive electric generators and other mechanisms operating in stationary conditions. Diesel engines 4Ch and 6Ch 36/45 are low-speed, however, they are directly connected to the shaft of the synchronous alternator supplied with the diesel engine. The generator is installed on a common foundation with a diesel engine.
The skeleton of these diesel engines consists of a foundation frame, a crankcase and cylinder covers, tightly connected to each other with studs. The base frame of a box-shaped rigid structure is cast iron. The main bearing housings are cast in one piece with the base frame, in which steel liners filled with babbitt are placed.
The crankcase of a diesel engine is one cast-iron casting, fastened to the foundation frame with anchor ties. Wet-type cylinder liners, cast iron, sealed with rubber rings from below. Cylinder covers for each cylinder are individually cast iron. Each cover contains: nozzle, inlet and outlet valves, air inlet and indicator valves. The cylinder cover is mounted on the liner shoulder along the annular recess sealed with a copper gasket.
Crank mechanism. The crankshaft is made of high quality carbon steel, solid forged; for diesel engines 4Ch 36/45 (G-60), the shaft has five main journals, and for diesel engines 6Ch 36/45 - seven. In the first case, the connecting rod journals of the shaft are located in one plane at an angle of 180 °, and in the second - in three planes at an angle of 120 ° to each other. In each knee there is an oblique drilling directed from the main to the connecting rod neck; it serves to supply oil to the connecting rod journal and through the connecting rod rod to the upper head of the connecting rod. The rear end of the shaft ends with a flange to which the generator shaft is attached. Between the flanges of the crankshaft and the generator, a disk-type flywheel cast from cast iron is fixed. The main journal closest to the flywheel is made wider than the others, since it is stubborn. The shaft, when expanding, can only lengthen in the direction opposite to the flywheel. Between the flanges and the thrust neck, a detachable camshaft drive gear is fixed with a clamp. The exit point of the crankshaft from the frame is sealed with a casing having a labyrinth and stuffing box seal.
Connecting rod of stamped steel two-tee section with detachable lower head. The lower head is made of two halves with steel liners filled with BN babbitt. It is centered in the rod of the connecting rod with the help of a protruding spike on the upper half of the head, inserted into the cavity of the rod. A bronze bushing is pressed into the upper head of the connecting rod. The piston is cast iron. The bottom of the piston on the outside has a concave shape. Its inner side is cooled by oil sprayed with a special fitting screwed into the upper head of the connecting rod. The piston has five o-rings and four oil scraper rings.
The piston pin is hollow, floating type; its surface is cemented and hardened by high-frequency currents.
The gas distribution mechanism consists of a system of gears, a camshaft, a valve drive and fuel pumps. The camshaft is located on the shelf of the crankcase in bearings, the steel liners of which are filled with babbitt. The cams of the intake and exhaust valves are mounted on the shaft, fixed on it with dowels. In addition, the shaft has cams of fuel pumps connected to it by means of bushings, which makes it possible to set the required advance angle of fuel supply. The camshaft is driven by the crankshaft gear through the intermediate gears. For smooth engagement and quiet operation, the drive gears are made with an oblique tooth. The valves are actuated in the same way as shown in Fig. 103.
The G-60 diesel fuel supply system consists of fuel pumps, booster pumps, injectors, fuel filters, and connecting pipelines.
The fuel pump is single-plunger, spool type. The operation of each cylinder is provided by its own fuel pump and nozzle.
Booster pump gear type. It is equipped with a bypass valve. When the diesel engine is running, fuel is supplied by a booster pump to a coarse filter, then by a furnace cleaning, after which it is already fed to a high-pressure fuel pump.
The coarse fuel filter consists of two sections mounted in a cast iron housing. Each section has an internal and external filter element. The filter element consists of a frame with a brass mesh stretched over it. The crane can turn off one of the sections for inspection and cleaning (with the second section running).
Fine filter two-section, mesh type, has inner and outer filter elements inserted one into the other. The brass mesh of both filter elements is stretched over corrugated sheet steel drums. Both sections of the filter are mounted in a housing, in the lower part of which there is a valve that allows one of the sections to be switched off from operation or both sections to be closed, cutting off fuel access to the diesel engine.
Closed-type diesel nozzles with slotted filter.
The engine regulator is centrifugal single-mode. It is driven by a large bevel gear elastically connected to the camshaft gear. The elasticity of the connection is achieved due to the springs through which the torque is transmitted and which soften the shocks arising from the uneven rotation of the crankshaft and camshaft.
Each position of the regulator clutch corresponds to a strictly defined amount of fuel supply. On the other hand, each position of the weights, and therefore the position of the clutch, corresponds to a certain number of revolutions. Therefore, with a change in load, there is still some change in the number of revolutions. In order to have a precisely set number of revolutions with a changed, new load, it is necessary to change the tightening of the springs pressing the regulator clutch. This is achieved manually or, with remote control, by a reversible electric motor supplied with the regulator.
The diesel has a cut-off mechanism that serves to connect the regulator and the diesel control handle with fuel pumps.
The G-60 diesel lubrication system is mixed. Cylinder liners are splash lubricated, all other moving parts are lubricated under pressure. A small number of units that do not require circulation lubrication are periodically lubricated by hand. All the oil circulating in the engine is in the base frame and oil sump. When the diesel engine is running, oil from the oil sump is sucked in through the intake filter by an oil pump driven by the crankshaft gear and pumped into the coarse filter, from where it enters the refrigerator, and then into the main oil line. In parallel with the coarse filter, a fine oil filter is included, passing through itself a part of the circulating oil, which then drains back into the oil sump. From the main line, oil flows to the main bearings of the crankshaft, and then through the holes in the cheeks and necks of the shaft to the connecting rod bearings and then to the upper head of the connecting rod.
For pumping the oil line before starting into the pressure line, there is a manual booster pump.
The intake filter of the mesh type consists of two filter elements placed in the oil sump. The filter element consists of a rigid metal frame wrapped in a brass mesh.
Gear type oil pump.
Coarse filter mesh type two-section. Two fine filters have three ASFO-type filter elements.
Tubular type oil cooler. Hot oil washes the copper tubes on the outside, while cold water flows inside them.
The diesel engine is cooled by running water supplied from a water tank or water supply. Diesel does not have a water pump. From the supply pipe, cooling water, washing the oil cooler, enters the lower part of the water jacket of each cylinder, then flows through the fittings into the cylinder covers. From here, water flows through the overflow pipes into the exhaust manifold jacket and then into the drain pipe.
The diesel engine is started with compressed air. Before starting, the cylinders are filled with compressed air pumped by the compressor. The compressor is a vertical two-stage single-cylinder. It is located separately from the diesel engine and is driven by an electric motor through a V-belt transmission. The compressor at n = 800 rpm has a capacity of 10 m3/h. Working pressure 60 at.
Starting valves are installed on all cylinder heads. The valves are controlled by compressed air supplied through a disc air distributor
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Description of the diesel engine 6CHRN36/45.
Diesel type 6CHRN 36/45 is a marine medium-speed reversible four-stroke diesel engine with a gas turbine supercharger and a single-row arrangement of cylinders - designed for installation on transport ships as the main engine. General view of the diesel engine 6ChRN 36/45. The plant produces four modifications of 6ChRN 36/45 type diesel engines with factory grades: G-60, G-70-5, G-70, G-74 (Table 2). All modifications are characterized by the following: pneumatic system of remote automated control (DAU); alarm and protection system; all-mode shaft speed controller; temperature controller for water and lubricating oil; the possibility of installing a gearbox with a diesel modification G-74; the ability to work without attendants in the ship's engine room for 24 hours. The diesel frame, the base frame, the frame and the cylinder block are cast iron, interconnected by anchor ties passing through special holes in the base frame to the upper plane of the cylinder block. The main crankshaft bearings have interchangeable babbitted bearings that can be removed without lifting the crankshaft. The diesel has a thrust bearing located in front of the flywheel. Cylinder bushings - cast iron phosphated. Cast iron cylinder covers have a nozzle in the center, and on the sides, along the axis of the crankshaft, inlet and outlet valves. The channels from the valves are brought to the side of the engine opposite to the distribution side. The valves have replaceable seats and guide bushings pressed into the cover. The working chamfer of the exhaust valve is welded with a heat-resistant alloy. Piston - cast iron, solid, phosphated, cooled by oil supplied through the connecting rod. The sealing piston rings are chrome-plated, and the oil scraper rings are tin-plated. The connecting rods are stamped, with an integral lower head. The upper head of the connecting rod has a pressed bronze bushing. Piston pin - floating type. The transmission to the camshaft is located on the flywheel side. Cam washers of valves and fuel pumps are removable. The cams of the fuel pumps can be rotated around the axis of the shaft, which simplifies the change in the phase of fuel supply to the diesel cylinder. Fuel pumps - spool type, individual for each cylinder, can be switched off during diesel operation. The fuel supply system has a gear fuel priming pump, two fine filters (fabric self-cleaning) and two coarse filters (mesh). To operate the diesel engine on motor fuel, the fuel system includes a fuel separator, electric fuel heaters and additional cleaning filters. The diesel engine is launched by compressed air from the wheelhouse, where the DAU post is located. The diesel oil system has: two oil pumps - pressure and exhaust, which ensures the principle of a "dry" sump, two oil pre-filters and one fine filter, two oil coolers and a thermostat to maintain the set oil temperature. Cooling system - closed double-circuit; the constancy of the water temperature is maintained by a thermostat.
Diesel engines of type 6CHRN36/45 G 70-5 are designed to operate as the main marine engines of river and sea vessels with power transmission directly to the mushroom shaft. To exclude the transfer of axial force from the propeller shaft to the crankshaft of the engine, an intermediate shaft is provided directly behind the flywheel with a thrust bearing connected through a coupling to the ship's shaft line. The thrust from the propeller shaft is perceived by the thrust bearing of the shafting or gearbox, if the latter is available.
Diesels are produced in two models: right (G70-5) and left (G70L-5).
Their design is identical, only the left model is a mirror image of the right model. In accordance with this, the design of their individual parts and assemblies of the same name has been changed.
general description
The foundation frame and cylinder block are sprinkled with anchor ties and bolts. Cylinder bushings are inserted into the block. From above, the cylinders are closed with cylinder covers, which are fixed on the diesel engine by means of studs screwed into the block. Each cover has an inlet, outlet and start valve, a nozzle, a safety-decompression valve.
The crankshaft rotates in seven base frame bearings. The shells of the frame and connecting rod bearings are filled with babbitt. The connecting rods are connected to the pistons by means of floating fingers. The pistons are oil cooled.
The intake and exhaust valves, as well as the fuel pumps, are driven from the camshaft, which, in turn, is driven from the crankshaft through a gear transmission.
On the side opposite to the distribution, there is a charge and exhaust manifold. They are connected to a turbocharger mounted on the rear end of the diesel engine.
At the rear end, in addition to the turbocharger, the following are installed: an air cooler, a speed controller, a starting distributor, a limit switch (safety controller).
A flywheel is attached to the flange of the crankshaft.
At the front end of the diesel engine there are: a control post, DAU system components, a fuel priming pump, water pumps (circulating and outboard water), oil pumps (pressure and pumping) and a tachometer sensor. The drive of the front end units is carried out from the crankshaft gear.
Separately from the diesel engine, coarse and fine fuel filters, coarse oil filters, a set of centrifuges, two oil coolers, a water cooler, oil pumps and thermostats are installed.
The diesel engine is equipped with a pneumatic remote automated control system (DAU), which allows you to control the operation of the diesel engine from the ship's wheelhouse. Separate components of the DAU system are built into the speed controller and into the diesel control post. Outside the diesel engine there is a remote post with a pressure stabilizer installed in the remote control post in the wheelhouse, as well as a DAU cylinder installed near the wheelhouse.
Table 5
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Trademark |
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Gorky zad Engine of the Revolution 1 |
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Year of issue |
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Four-stroke, single-row, with a vertical arrangement of cylinders, with a gas turbine pressurization, automated - with a DAU system. |
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Rated power under normal conditions: |
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Maximum power under normal conditions: |
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Operation at maximum power |
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Rated speed, rpm |
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Maximum speed, rpm |
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Compression ratio |
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Compression volume |
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Direction of rotation of the crankshaft (flywheel side) |
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Number of cylinders |
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The order of operation of the cylinders |
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Cylinder diameter |
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piston stroke |
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Cylinder displacement in liters |
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Compressed starting air pressure |
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The left diesel engine is identical to the right one, except for: the factory brand - G70L-5, the direction of rotation of the crankshaft (from the flywheel side) - left, and the order of operation of the cylinders - 1-4-2-6-3-5 |
Pressurization system.
Compressed air is used to start the engine. The air supply is controlled by the main starting valve, air distributor, starting valves. Compressed air can be forced into air balloons using a compressor. The gas-turbine heater attached to the movement consists of a drive turbine and a compressor. It is used to pressurize the energy resources contained in the exhaust gases.
Designed to increase engine power
- 1) Type and brand of supercharger: PDH-50 gas turbine system
- 2) Number of revolutions: 18000.
Gas distribution mechanism.
The intake and exhaust valves are driven by camshaft cams.
When the camshaft rotates, the cam washers act on the roller and open the valves through the slider, rod and rocker. The valves are closed by springs when the slider roller runs onto the cylindrical surface of the cam.
The roller rotates on the sleeve, the latter rotates around an axis that enters the holes of the slider. The bar rests on the bottom of the cracker, and on top of the rocker pusher.
The lubrication of parts moving in the body is carried out as follows: through the nipple, oil enters the annular groove of the body, from where it goes through the groove and drilling in the slider to the axle drilling, and from them to the bushing drilling.
Fuel system
From the fuel tank, fuel enters the fuel priming pump, which supplies it to the coarse and fine filters. Excess fuel through the bypass valve is discharged into the suction pipe of the fuel priming pump.
The filtered fuel enters the main line, at the beginning of which there is an air cooler, and from there through metal-rubber hoses to the fuel pump.
Fuel pumps pump fuel through pipes to the injectors. The nozzles are cooled by fuel supplied through pipes from the main line. The cooled fuel is drained through tubes into the drain pipeline.
Fuel leaks from injectors and fuel pumps through pipes and are discharged into a common drain pipe, and from there into two drain tanks.
A tube from the drain hole of the fuel priming pump is connected to one of the barrels.
During normal diesel operation, valve A is closed and valve B is open. When measuring fuel consumption, it is necessary to open valve A and close valve B. There are pressure gauges in the fuel system that show the fuel pressure before and after the fine filter.
Lubrication system
The diesel lubrication system is combined, with a dry sump. Lubrication of all main components and assemblies is carried out with oil supplied under pressure through a special pipeline.
Several nodes located in the diesel crankcase are lubricated with oil sprayed by moving parts. A small number of lightly loaded parts are manually lubricated.
Cooling system
The cooling system is double-circuit, the water of the internal circuit cools the diesel engine, and the external circuit serves to cool the water of the internal circuit and the oil of the diesel oil system.
In the outer circuit - outboard water. It is pumped, passes through an air cooler, then enters the water and oil coolers and drains back overboard.
Fresh water circulates in the internal circuit. Its circulation is carried out using a circulation pump.
The pump supplies water to the main line, from which it goes to the cylinder block to cool the cylinder liners and covers. At the end of the main line, water is drained to cool the turbocharger.
The water that has cooled the cylinders of the diesel engine and the turbocharger, through overflow pipes with control valves and mercury thermometers, enters the drain line. At the end of the drain line there is a thermostat that directs part of the hot water flow (depending on its temperature) through the refrigerator, where it is cooled. The rest of the hot water bypasses the refrigerator. The cooled water is again sucked in by the circulation pump and fed into the diesel engine. To compensate for the expansion and loss of water, the internal circuit of the cooling system must have an expansion tank.
The operation of the cooling system is controlled by instruments located on the instrument panel. In addition, when the water leaving the diesel engine overheats, a light and sound alarm is triggered. The temperature relay sensor is installed on the drain line (8) and the temperature of the water leaving the cylinder covers is maintained within + -2? C from the average value.
No. 1 Location of equipment in the engine room. Scheme of the plan of the engine room with the specifics of all equipment.
№ 2 List the main technical and economic indicators of the main and auxiliary diesel engines. Used grades of fuels and oils. Diesels of type 6ChRN 36/45 (G60, G70, G70-5) are designed to operate as the main marine engines of river and sea vessels with power transmission either directly to the propeller shaft or through a highly elastic tire coupling. Diesel engines are produced in two models: right (factory mark G60, G70, G70-5) and left (factory mark G60l, G70l, G70l-5). Their design is identical, only the left model is a mirror image of the right model.
Specification. 1. Factory brand (right model) G60; G70; G70-5. Factory brand (left model) G60l; G70l; G70l-5. 2. Designation of the diesel engine according to GOST 4393-74 6ChRN 36/45 3. Long-term rated power at G60; G70; G70-5. shaft flange in forward gear at rated speed and relative humidity of 70%, exhaust backpressure not higher than 50 ohms. - no more than 180 mm w.c. in hp 900 - 1000 - no more than 180 mm w.c. in hp 1200 4. Maximum power in forward gear at maximum speed for one hour, but not more than 40% of the total duration of diesel operation with intervals between overloads of at least 5 hours in hp. under the conditions of paragraph 3. 990 1320 1100 5. Continuous reverse power at the number of revolutions of the number shaft - 356 0 rpm 765 1020 - - 322 rpm - - 850 6. Rated revolutions per minute 375 375 350 7. Number cycles 4 4 4 8. Number of cylinders 6 6 6 9. Cylinder arrangement vertical, in-line 10. Single-acting diesel engine, reversible, trunk-type, with gas turbine supercharging. 11. Bore mm 360 12. Stroke 450 13. Displacement in liters 45, 78 14. Compression ratio 11 15. Average piston speed at nominal speed, in m/s 5.63 5.63 5.25 16 .Rotation direction. For diesel engines of right rotation, the crankshaft rotates clockwise in the forward direction. For diesel engines of left rotation, the direction of rotation is opposite. 17. Fuel: a) Main motor diesel fuel according to GOST 1667-68 with sulfur content not more than 1.5%, coking content not more than 3%. b) Substitutes: - motor fuel grade 4 and 5 "light" according to ASTM 39667 specification (USA), - fuel 200 from Shelley. – motor fuel according to the Din51603copm “L” standard (Germany). c) Auxiliary: - diesel fuel according to GOST 305-73; - diesel fuel according to GOST 4749 - 73; - diesel fuel according to specification MF-16884F (USA); - diesel fuel grade 47/odiESO and 47/2odiESO according to specification DEF-24028 (England). 18. Specific effective fuel consumption at rated power, reduced to fuel calorific value 10200 kcal/kg motor fuel 166+8.5 164+8.5 165+8.5 diesel fuel 158+8.0 157+8.0 158+ 8.0 19. Hourly fuel consumption at rated power, reduced (10200 kcal / kg, kg / hour). Motor fuel 149.5 196 165 Diesel fuel 142.2 188.4 158 -castrolSRB; -Mobiloil;
№3 Design features of fixed and moving parts of main diesel engines. Scheme of tightening anchor ties, diagram and description of the piston assembly and crankshaft. The foundation frame and the cylinder block are fastened with anchor ties and bolts. Cylinder bushings are built into the block. From above, the cylinders are closed with cylinder covers, which are fixed on the diesel engine by means of studs screwed into the block. On each cover there are inlet, outlet and starting valves, nozzles, safety - decompression valve. The crankshaft rotates in seven base frame bearings. Liners of frame bearings are filled with babbitt. The connecting rod bearing shells are made of bimetallic strip. The connecting rods are connected to the pistons by means of floating fingers. The pistons are oil cooled. The drive of intake and exhaust valves, as well as the drive of fuel pumps, is carried out from the camshaft, which in turn is driven from the crankshaft through a gear transmission. On the side opposite to the distribution, the charge and exhaust manifolds are located, as well as the air cooler, the speed controller. A flywheel is attached to the crankshaft flange. To reduce the reversal time, diesel engines can be equipped with a shoe brake acting on the flywheel rim.
Foundation frame.
Cylinder block.
Cylinder cover
Crank mechanism.
Silicone damper
#4 Describe the camshaft system. Scheme of the camshaft drive, a circular diagram of the gas distribution phases of the main diesel engine. Camshaft. The camshaft is steel, rotates in seven bearings. In addition, there are two more bearings that cover the camshaft gear hub. The shaft on the flywheel side ends with a cone, on which, using a key, nut 15 and washer 14, a slotted sleeve 13 is attached, which will connect the camshaft and camshaft gear. The diesel engine is reversed by axial movement of the camshaft. In this case, the gear 10 is kept by its bearings from axial movement. Connected to the gear 10 is a bevel gear 11 of the speed controller drive. For each cylinder, the camshaft is equipped with cam washers 2 and 9 for driving the intake and exhaust valves and a cam 6 for driving the fuel pump. The valve drive washers as well as the fuel washer bushing are mounted on the shaft with a slight interference fit and fastened to the shaft with keys and pins 3.
The fuel washer is dressed on its sleeve with a small diametrical clearance and engages with it with the help of teeth. Constant power closing of the teeth of the bushing and the washer is provided by the nut 8 . Such a device allows you to adjust the angle of advance of the fuel supply. To facilitate the landing of the cam washers, the camshaft is made stepped with an increase in fitting diameters towards the middle and a decrease towards the ends of the shaft. Accordingly, the diameter of the mounting holes in the cam washers and in the bushings of the fuel washers also changes. The cam washers are made of chromium steel, case-hardened and hardened. The valve drive washers have two working profiles (for forward and reverse). The profiles are connected by a smooth transition. On the side of the front end of the diesel engine, the camshaft has a special cracker (20) for connection with the body of the stoppers, the servomotor of the local control station on the diesel engine. During axial movement of the distribution rollers of the valve drive sliders, they move from one profile to another, sliding along the transition surface of the cam washers.
The camshaft is driven by the crankshaft gear. Gear 1 is engaged with the intermediate large gear 5, a small intermediate gear 7 is attached to the latter with the help of bolts 8 and nuts 9. The small intermediate gear is engaged with the camshaft gear 10, which rotates in bearings 12 and 13. on one side it is attached and pinned to the cylinder block, and the other end enters the hole of the traverse 6, installed and pinned on the foundation frame. The camshaft drive is located on the flywheel side and is closed by a casing.
Distribution mechanism
The intake and exhaust valves are driven by camshaft cams. When the camshaft rotates, the cam washers act on the roller 4 and open the valves through the slider 3, the rod 12 and the rocker. The valves are closed by springs when the slider roller runs over the cylindrical surface of the cam. The roller 4 rotates on the sleeve 7, the latter rotates around the axis 5, which enters the hole of the slider 3. The rod 12 rests on the bottom of the cracker 11, and on top of the rocker pusher. The lubrication of the parts moving in the body 2 is carried out as follows: through the nipple 8, the oil enters the annular groove of the body 2, from where it goes through the groove and drilling in the slider 3 into the drilling of the axis 5, and from them into the drilling of the sleeve.
№5 Scheme and description of the fuel system. Filtered and heated to a temperature of 85 + 95, motor fuel enters the main line, and from there to high-pressure fuel pumps 2, which, in turn, supply it through nozzles 3 to the engine cylinders. The fuel that has leaked between the plunger and the sleeve of the high-pressure pumps flows into the drain tank 5. The nozzles are cooled by diesel fuel, which is supplied by pump 1 to the common line. From the common line, the fuel enters through the branches to cool the injectors, after which it is sent to the external pipeline. The bypass valve 4 of the booster pump 1 serves to bypass fuel from the discharge to the suction cavity in case of clogging of the injector cooling pipeline. When the engine is running on diesel fuel, the latter follows the path of motor fuel.
№ 6 Scheme and description of the lubrication system. The diesel lubrication system is combined, with a dry sump. Lubrication of all main components and assemblies is carried out with oil supplied under pressure through a special pipeline. Several nodes located in the diesel crankcase are lubricated with oil sprayed by moving parts. A small number of lightly loaded parts are lubricated by hand.
Scheme of external pipelines of the lubrication system.
Scheme of internal pipelines of the lubrication system.
№7 Scheme and description of the cooling system. The cooling system is double-circuit. The water of the inner circuit cools the diesel, and the outer circuit serves to cool the water of the inner circuit and the oil of the diesel oil system. In the outer circuit - outboard water. It is supplied by pump 2, passes through air cooler 16, then enters water-to-water and oil-to-water coolers and drains back overboard. Fresh water circulates in the internal circuit. Its circulation is carried out using a circulation pump 1. Pump 1 supplies water to the main line, from which it goes to the cylinder block 15 to cool the cylinder liner and covers. At the end of the main line, water is drained to cool the turbocharger 10. The water cooling the diesel cylinders and the turbocharger, through overflow pipes with control valves and mercury thermometers 9, enters the drain line 8. At the end of the drain line there is a thermostat 3, which directs part flow of hot water (depending on temperature) through the cooler 5, where it is cooled. The rest of the hot water bypasses the cooler. The cooled water is again sucked in by the circulation pump and fed into the diesel engine. To compensate for the expansion and loss of water, the internal circuit of the cooling system must have an expansion tank 4. It is recommended to use soft fresh water with the addition of 1% chromium peak in the internal circuit. The operation of the cooling system is controlled by instruments located on the instrument panel 12. In addition, when the water leaving the diesel engine overheats, a light and sound alarm is triggered. The temperature switch sensor is installed on the drain line 8. The temperature of the water leaving the cylinder covers is maintained within the average value. When installing on a diesel engine in the cooling system, pour 1/2 of the volume of the shank into the shank of the shank with technical oil.
№8 Scheme and description of the compressed air system. The diesel engine is started with compressed air. Air is stored in starting cylinders 3, where it is pumped by a compressor through a check valve 1. The air pressure in the cylinders is controlled by a pressure gauge 4. From the starting cylinders, the air goes to the main starting valve 5 and to the air reducer 11 through the dehumidifier 10. From the reducer 11 air with a pressure of 10 and is fed to the power of the local control post and to the DAU cylinder 14 installed in the wheelhouse next to the remote control post 18. A blocking valve 36 is installed on the power supply line of the local control post, which prevents the diesel engine from starting after the limit switch has been triggered. On the air supply line to the distributor 9, a start blocking valve of the mechanized barring device 8 is installed. Start accelerators 30 (not shown in the diagram) are used to reduce air consumption during start-up by bringing the fuel pump rails to the starting fuel supply. An accumulating cylinder 12 with a check valve 13 is included in the air supply pipeline to the accelerator, which serves to extend the response time of the launch accelerator. During start-up, the DAU pneumatic system provides control air supply to the main starting valve when the steering wheel of the control station on the diesel engine or the roller of the remote station is turned to the "start" or "work" position. Through the open main starting valve 5, compressed air enters the main line 37, from which it is supplied to the starting valves of 6 cylinders. The air distributor pneumatically controls the valves 6, opening them in the order of the cylinders. As a result of this, air rushes into the diesel cylinders and spins the crankshaft, ensuring the start of the diesel engine. When delivered by a diesel engine with mechanical shoe brakes 28, air to the brakes is supplied from the speed relay 26 along line 57, unloading is carried out by valve 27.
№ 9 Scheme and description of the starting - reversing device. Self-cleaning throttles 15 are installed in the control cavities of the starting valves, which connect the control cavities with the aplussphere and reduce the diesel reversal time, since the control cavity is unloaded simultaneously through the air distributor and throttles, and the delay time for the end of closing the starting valve is sharply reduced. The starting air supplied from the main starting line into the internal cavity of the body 1 presses down on the valve disc and up on the valve piston, balancing the forces. In this state, the valve is closed. The operation of the valve is controlled by an air distributor, which supplies control air to the over-piston space through the nipple16. Control air presses on piston 3 and opens the valve, starting air enters the diesel cylinder. Reverse unloading is carried out by a self-cleaning throttle 17. The compressed air remaining in the starting valve is vented to the atmosphere and the starting valve closes. The slotted connection of the spool is sealed with a spool cap 9 and gasket 13. When the diesel engine is reversed, the camshaft, moving along the axis, turns the distributor shaft with a pin that enters the spiral groove of the air distributor shaft, and thereby the spool will be set to a position that provides start in the opposite direction. Flange 6 serves for centering and installation of the air distributor.
№ 10 Management and regulation of ship engines. Kinematic diagram of the crankshaft speed controller. When the diesel engine is controlled from a remote control station, the speed controller works like a normal one, i.e. any diesel speed set in the operating range is supported by the speed controller. When driving a diesel engine from a local post, the speed controller acts as a limit, in this case, the diesel speed depends on the position of the steering wheel of the control station on the diesel, which, when controlled from the diesel post (the steering wheel is pushed in), is rigidly (one-sided) connected to the cut-off mechanism. The speed controller and the steering wheel of the post on the diesel engine are connected to the plungers of the fuel pumps by a cut-off mechanism. The speed control system maintains a constant speed of rotation of the engine crankshaft in accordance with the task (the value of the pneumatic signal or the handle on the front panel of the regulator). The adjustment of the engine speed mode depending on the task occurs by reducing or increasing the fuel supply. This task is performed by a speed controller connected to the plunger and fuel pumps by a cut-off mechanism.
Figure speed controller
Depending on the task, the tightening of the all-mode regulator spring changes (using a hydraulic booster built into the regulator), and, consequently, the position of the fuel pump rails, and with an increase in the tightening of this spring, the fuel supply increases and vice versa.
Regulator drive
№11. Scheme and description of ship pumps and ejectors, if any.
Ship pumps, according to the purpose of the systems they serve, are divided into general ship pumps (fire, ballast, drainage, sanitary, etc.) and pumps related to power plants (feed, fuel, oil, circulation, condenser, etc.)
According to the principle of operation, ship pumps can be: piston, in which suction and discharge are provided with the help of a reciprocating piston;
Bladed (centrifugal and propeller), providing suction and injection of fluid by rotating the impeller with blades;
Rotary-vane and vortex, achieving a pumping effect with the help of rotating displacers (rotors);
Gear (gear), in which the suction and discharge of liquid is carried out by means of a pair of gears;
Screw, in which the pumping of fluid is provided by the rotation of one or more screws (augers);
Jet (ejectors and injectors), pumping liquid using a jet of working fluid, steam or gas.
According to the type of energy used, pumps are divided into manual, steam, electric, hydraulic and driven by internal combustion engines, turbines and steam engines.
According to the type of pumped liquid, pumps are water, oil, oil, fecal, etc.
Piston pumps have a high suction capacity, the ability to regulate the flow without changing the pressure, a simple design and relatively low requirements for cleanliness of processing and fit of parts.
Rotary vane and vortex pumps, inferior to piston pumps in suction capacity and in some other qualities, have their own advantages and are widely used on modern ships with an electric drive.
Screw pumps are most efficient when pumping clean, viscous liquids.
Jet pumps, on the contrary, are very uneconomical, but are indispensable for some intermittent systems (drainage) and, due to their simplicity of design, are very convenient for pumping contaminated liquids.
Other types of pumps are also used in view of their specific advantages (gear pumps as lubricants, rotary vane pumps in blowers, etc.).
№12Ship auxiliary boilers (steam, hot water, waste heat). Boiler diagram.
An auxiliary boiler is a heat exchanger in which water is heated to a certain temperature or steam is produced.
In the boiler plant, the energy of the fuel is converted into thermal energy of water vapor. In this case, the processes of fuel combustion, heat transfer from combustion products to water and its vaporization take place. Such boilers are called steam. The ships are equipped with hot water boilers that meet ship's hot water needs.
The initial carrier of thermal energy in boilers, along with fuel (such boilers are called autonomous), can also serve as the exhaust gases of diesel engines. In the following, they are called recovery boilers.
The main characteristics of the units are nominal capacity, nominal power (heating capacity), operating steam pressure (water temperature) and heating surface area.
Boilers - utilizers. With the rational use of the heat of the exhaust lawns, they can increase the efficiency of the power plant by 5-8%. Waste-heat boilers in the SPP system also play the role of noise silencers. The automated gas-tube waste heat boiler KAU-4.5 with a heating surface area of 4.5 m 2 is included in the heating and hot water supply system of ships and can operate in natural and forced circulation modes.
As steam on ships, water-tube boilers KUP 19/5 and KUP 15/5 with a nominal steam output of 250 and 175 kg/h and a heating surface area of 19 and 15 m 2 are widely used.
On river boats as hot water widely used automated gas-tube boilers KOAV 68 and KOAV 200, which have the same design. Boilers differ in size, heating surface area and power. The power of boilers KOAV 68 is 79 kW, and that of boilers KOAV 200 is 232 kW.
№13. Water desalination plants.
Providing passengers and crew with drinking water is a very responsible task.
Outboard water without special treatment and filtration, as a rule, is unsuitable for drinking. Therefore, ships are supplied with water from the city water supply, or they clean it from suspended mineral particles and disinfect it. Drinking water pipelines are made of galvanized steel pipes with a diameter of 55 mm - for mains and 13 - 38 mm for offshoots.
Water treatment plants of large modern cargo-passenger ships are a complex set of elements. The sanitary system includes: an electrolyzer tank used for sea water coagulation, a pressure sand filter, devices for sterilizing (ozonizing) filtered water, tanks for storing filtered water, pumps for supplying water to the system and for washing the filter, as well as devices automation.
Water is purified from mechanical impurities using filters (sand, quartz, ceramic). To combat pathogenic bacteria, water is chlorinated, treated with silver ions, irradiated with ultraviolet rays or ozonized.
Ozonation makes it possible to obtain high efficiency of water treatment with the help of relatively simple equipment and to dispense with the strict dosage of introduced disinfectants, which is necessary for other methods of water treatment (chlorine, silver water and other reagents).
№14Descriptionactionwatchmanminderatstart-up, stop, servicemajorengines.
Diesel start.
To start a diesel engine from the engine room, it is necessary.
Turn off the remote control and turn on the alarm and protection system;
Open the valve of the starting cylinder;
For diesel engines starting with prechamber heating, turn on the electric heating coils 30 s before starting;
For diesel engines with separate control, set the handle (handwheel) of the all-mode regulator to the position corresponding to a low speed; when manually adjusting the fuel supply, put the handle of the control station to the "Start" position in the direction of forward or reverse (depending on need) or press the starter button and start the diesel engine;
For diesel engines with an interlocked control system, move the handle (flywheel) of the control station to the "Start" position in the direction of forward or reverse (depending on need) and start starting;
As soon as the diesel engine starts to run on fuel, move the handle (handwheel) of the control station to the “Work” position, if there are prechamber heating coils, turn them off;
If the start fails, put the handle (handwheel) of the control station to the "Stop" position, and then repeat the start;
Verify by ear after starting the diesel engine in its normal operation, and by instruments - in the correct operation of the lubrication systems and the cooling system. Be sure to check the uniformity of the turbocharger (by ear), the circulation of cooling water, the uniformity of heating of the surface of the turbocharger housing.
Diesel stop.
Before stopping the diesel engine, reduce the crankshaft speed. For diesel engines with a reverse gear, after reducing the speed by 50%, it is necessary to turn off the reverse gear and let the diesel engine run for 3-5 minutes at idle. It is possible to stop the diesel engine only after the temperature of the cooling water in the closed circuit drops to 60%
A diesel engine running on motor fuel must be switched to diesel fuel 10-15 minutes before stopping.
If for some reason the diesel engine was stopped at full speed, it is necessary to pump oil through the lubrication system using a backup oil pump and turn the crankshaft with a barring mechanism to ensure its uniform cooling, and leave the engine fuel preparation system on.
When the diesel engine is stopped for more than 2 hours, it is required to drain the motor fuel from the pipelines of the fuel system, fill them with diesel fuel and bleed the high-pressure fuel pumps and injectors.
If the diesel stops for a long time, you should:
For diesel engines with oil-cooled pistons, pump the lubrication system for at least 10 minutes;
Replenish the air launch cylinders with air, bringing the pressure in them to normal;
Close the shut-off valve at the launch cylinders and release air from the pipes;
Open the indicator cocks on the working cylinders and turn the crankshaft 2-3 turns;
Close the cock on the fuel line to the fuel pumps and the valve on the water cooling suction pipe;
20-30 minutes after stopping the diesel engine, remove the covers from the crankcase hatches, check the temperature of the crankshaft bearings, the upper heads of the connecting rods, as well as the lower parts of the piston and cylinder bushings, the housing of the camshaft bearing regulator, valve drives and other rubbing parts and connections ;
For two-stroke diesel engines and supercharged diesel engines, open the drain valves on the air receivers to remove water and oil accumulated in them;
Turn off the oil supply through the central oil distributors for those diesel engines where they are available;
Wipe the diesel engine by replacing the covers removed from the crankcase hatches; lubricate manually the parts that do not have centralized lubrication;
Eliminate all malfunctions previously detected during diesel operation and inspection.
Diesel 6ChRN36/45(G-70). Diesel engines 6ChRN36/45 (G-70) - are used as the main engines of sea and river vessels.
Figure 6.1 - Longitudinal section of the diesel engine 6ChRN36 / 45 (G-70)
Figure 6.2 - General view of the diesel engine 6CHRN36 / 45 (G-70)
Design. The main parts of the diesel frame - the foundation frame and the cylinder block - are tied together by anchor ties that extend from the bottom of the frame to the upper plane of the block. The block has plug-in bushings on which the cylinder covers rest. The covers contain one inlet and one outlet valve, start and safety-decompression valves, a nozzle and a thermocouple. The main bearings have interchangeable, thin-walled, babbitt-filled bearings. The main bearing caps are attached to the foundation frame with anchor studs. Connecting rod bearings steel, thin-walled, with anti-friction aluminum alloy. The connecting rod cap is secured with four bolts. A bronze bushing is pressed into the upper head of the connecting rod. The piston is cast iron, cooled by oil, which comes from the circulating lubrication system. Piston pin floating type. Oil, water and fuel pumps are driven from the crankshaft gear. The camshaft is driven through a system of cylindrical gears. The camshaft controls the intake valves and fuel pumps and at the same time drives the speed controller, air distributor and tachometer. Cams of inlet valves and fuel pumps are removable. The cams of the fuel pumps can be rotated around the axis to control the moment of fuel supply to the cylinders.
The fuel system includes a service fuel tank with a receiving filter, an intermediate strainer, two fine filters, a gear fuel priming pump, spool-type fuel plunger pumps - one per cylinder and injectors. Intermediate and fine filters - two-section. They can be cleaned without stopping the diesel engine. Diesel engines (except G72m) can be equipped with an automated dual-fuel (diesel, engine) fuel preparation system.
The fuel preparation system has two pumps with an electric drive (one is a backup), a fuel separator, heaters and a fuel distributor, a control panel, an additive dispenser, a fuel cooler after the injectors, pre- and fine filters. A constant crankshaft speed is maintained by a precision speed controller that is connected to the fuel pumps. Control of the speed controller is local (handle) and remote (from the generator board). With the help of the fuel pump control mechanism, the speed controller and the control handle are independently connected to the fuel pumps. Marine diesel engines have an all-mode speed controller that maintains any given speed in the operating range, there is also a safety controller that automatically stops the diesel engine when the speed exceeds the specified limit. Diesel engines are equipped with equipment and mechanisms for emergency protection and signaling. In case of overheating of oil or water, a drop in their pressure, exceeding the permissible limits of the speed, an impulse will be sent from the corresponding sensor to the actuators and mechanisms. During an emergency stop, the access of air to the diesel cylinders is blocked, and the fuel pumps are turned on. At the same time, the generator is disconnected from the network (for stationary diesel engines).
The lubrication system for diesel engines is circulating. Oil is supplied to the system by a gear pump. Marine diesel engines have two pumps (injection and exhaust), which are driven by the damper gear of the crankshaft. The oil is cooled by running water in a tubular type cooler. The filter is two-section with mesh replaceable elements, fine oil cleaning is carried out by a centrifugal filter, which operates under pressure in the lubrication system. The system is equipped with a thermostat that maintains the oil temperature within a strictly set range. Before start-up, the lubrication system is pumped and filled with oil by an independent electric gear pump. Marine diesel engines have two pre-start pumps, two pre-filters and one centrifugal oil filter. A turbocharger is connected to the diesel lubrication system.
The cooling system of diesel engines is closed, two-circuit. In the internal circuit with a centrifugal pump driven by the crankshaft, fresh water circulates, which is cooled in a tube-type cooler. The water of the external circuit is pumped through the cooler by an autonomous electric pump. For marine diesel engines, the sea water pump is mounted on the diesel engine and is driven from the crankshaft damper gear. The temperature of the water in the internal circuit is maintained within the set interval by a thermostat. To replenish leaks and evaporate water, the system is equipped with a compensation tank.
The air intake system is equipped with an air cleaner. Between the turbocharger TK-30 and the supercharging manifold there is a damper of the emergency protection system, which, when it is triggered, blocks the access of air to the manifold. The charge air passes through the cooler before entering the cylinders.
At the front end of stationary diesel engines, oil-water and fuel-priming pumps are installed, which are driven from the crankshaft, the main starting valve, a tachometer with a drive and a control handle. On the same side, next to the diesel engine, a panel with instrumentation is installed. At the front end of the marine diesel engines there is a control post, a mechanism and devices of the DAU system, a fuel priming pump, water pumps (circulation and evacuation), a torsional vibration damper (installed according to the calculation results) and a tachometer sensor.
Marine diesel engines are equipped with a pneumatic remote automated control system (DAU), which allows you to control the operation of the diesel engine from the ship's wheelhouse. The diesel engine can be started and stopped by the steering wheel of the local control station on the diesel engine or from the wheelhouse by the handle of the DAU station. Control and measuring devices are installed in the engine room on a remote panel and in the wheelhouse on the DAU control panel.
The main parameters of diesel engines 6CHRN 36/45 (G-70).
Table 6.1 - Main parameters of the diesel engine 6ChRN 36/45 (G-70)
Table 6.1 continued
| Average effective pressure on a nominal mode, 10ah H / m "- | 10,22 |
| Average piston speed, m, s | 7,5 |
| Fuel | |
| basic | Motor diesel fuel (GOST 1667 - 68) |
| auxiliary and substitutes | Diesel S (GOST 305 - 62), DS and DL (GOST 4749 - 49) or TL (GOST 10489 - 69) |
| Specific fuel consumption, reduced to the calorific value of fuel, g, (kWh) [g (e.l.s.h)], not more than: | |
| motor | 220+5%; |
| (162+5%) | |
| diesel | 213+5% |
| (157+5%) | |
| Lubricating oil: | |
| basic | MI2B MRTU 12 N 3-62 |
| substitutes | DS-11 (M10B) GOST 8583 - 61; Dp11 GOST 5304 - 54 (when operating on fuel 0GOST 4749 - 49); MS-20 GOST 1013 -- 49 (at elevated ambient temperature) |
| substitutes for foreign | SAE 30 USA Std M-1-1.-2104-B; |
| stamps | SAE Brit(h Btd. DE F 2101-B |
| Specific oil consumption, | 5. 4 (4) |
| g (kWh) [g,(e.l.s h)] | |
| Diesel dry weight, t | 29.0 |
| Gear ratio of the gearbox; | - |
| Diesel resource before the first bulkhead (removal of pistons) | 7 000 |
| Diesel resource (motor resource), h | 35 000 |
Diesel generator AD150 (YaMZ 238DI).
