Marine marine diesel engine when running emergency repair
First, seal cylinders of diesel engine running
Diesel engine running if one or more of the moment by faulty cylinder cannot be repaired, you can stop it
Measure of cylinder runs with disabilities, that seal cylinder to run.
1, cylinder runs three scenarios and solutions
(1) stop the cylinder oil ignition
If you have a cylinder fails, such as system failure, valves, cylinder leak bitten to death, which simply make the cylinder not firing and moving parts can still be running. In such cases, according to the specific circumstances of diesel engine injection pump wheel may be instituted, causes the fuel pump to stop working or open Injector valve back, to stop the fuel injected into the cylinder. But avoid close the import and export of fuel injection pump valve, resulting in dry grinding of injection pump coupling were bitten to death. Run or also known as reduction of such cylinder cylinder cylinder runs.
If it is a DC two-stroke diesel engine, while stopping injection, exhaust valve should also be locked in open position, in order to reduce the consumption of piston compression work.
(2) remove piston Kit, cross head and Rod stay inside the machine
If the piston, cylinder head or cylinder crack or damage that cannot be repaired, but link and crosshead is still functioning, you must remove piston Kit (including stuffing), and to take the following measures:
① lift the wheel stops for fuel pump pump oil;
② Bend flow scanning close cylinder exhaust gas with special tools, uniflow scavenging or four-stroke diesel engines valve locks
In the normal closed position;
③ seal piston rod stuffing holes with special tools;
④ cross head is installed on dedicated the cover;
⑤ enclosed piston cooling system;
⑥ disassemble the cylinder valve controlled air tube and seal;
⑦ Remove cylinder Starter starting air valve pipe and seal;
⑧ close cylinder cooling water imports and exports of the cylinder valve;
Issues to minimize the cylinder cylinder injection tubing;
⑩ piston Kit remove then reinstall cylinder head.
(3) piston, connecting rod, cross head all split out
If connecting rod, severely damaged cross head or guides, bearing damage, you need to remove all the moving parts. In addition to taking the second of these measures, also need to take the following measures:
① oil hole in the crank pins in the clamp closed;
② close crosshead lubrication system.
, A 2 cylinder closure operation of emergency treatment
Should, as appropriate, reduce the running speed of diesel engine cylinder run time, you can select the appropriate speed to maintain navigation according to the following principles:
① cylinder exhaust temperatures exceeding the calibration value is not allowed;
② exhaust gas turbocharger surge does not occur;
③ the abnormal vibration of a hull or body does not occur;
④ minimize the starting number.
Second, stop supercharger of diesel engine running
Supercharger in diesel engine run damage (such as fracture of bearing burning, Blade, etc) and cannot be repaired, you diesel engines should go
Stopped into the supercharger emergency runs. Turbocharger technology for treatment of failure (such as locking hinges, or hanging out the hinge), while diesel recovery operation as soon as possible.
1 stop, four-stroke diesel engine turbocharger running
Stops turbocharger running the equivalent of four-stroke diesel engine non-turbo-charged diesel engine. Rely on the piston's suction effect at this time, you can still complete the breath stroke, diesel engines can still be functioning. But because of its cylinder charging significantly reduced, running power and speed will drop significantly.
If you need long-term operation, you should increase the compression ratio compression pressure to lower exhaust temperature; adjust valve timing, reduced valve overlap angle down so as not to waste gas flushing; suitable reducing valve clearances in order to avoid stem impact.
2 run stopped, two-stroke diesel engine supercharger
When the two-stroke diesel engine supercharger runtime itself gas exchange process could not be completed and cannot be run. Measures taken vary depending on model. Such as Sulzer RTA, and emergency measures were taken by the MAN-B&WL-MC model:
① starting electric auxiliary blower;
② turbocharger shaft fixed at both ends using the special tools, such as emergency operation takes a long time, you should pull the rotor and
Cover seal turbocharger shell at both ends;
③ removed from the exhaust by-pass pipe closed under blind Board, allows exhaust gas bypass to the chimney.
Three, diesel engine cylinder
1, pull cylinders phenomenon, causes and signs before scuffing
See the 6th page.
2, when the cylinder of emergency treatment
① early when a cylinder is found to be first of all increase the amount of oil cylinder lubricating oil. If overheating has not changed, you can take single cylinder
Stop oil, reduce speed, strengthen piston cooling measures, until the heat eliminated.
② When the cylinder is detected, must be rapidly reducing speed, and then stop. Continue to increase the piston cooling, while turning.
But do not strengthen the cylinder cooled, otherwise it will exacerbate cylinder, making accidents more deterioration.
③ When Pistons bitten to death do not allow such as turning, piston cooling after a period of time, and then turning to activities.
④ When more serious when Pistons bitten to death, kerosene can be pumped into the cylinder, piston cooling after move the handwheel or disk
Car. If the Pistons still not action, lifting bolt can be mounted on a crane on top of piston a piston. When lifting edge into kerosene, beat Pistons top edges with a soft metal rod, slowly lifting piston to prevent lifting bolt pull off or lifting screw hole broach bad.
⑤ lifting cylinder inspection, piston and cylinder liner should be traces on the surface of the cylinder with oil stone Grind. Damaged piston rings
Shall be renewed, if the Pistons and cylinder was badly damaged and should be replaced.
⑥ When Pistons refitted, you must carefully check the oiling hole on the cylinder oil is normal. If the Pistons and cylinder sleeves are for
New, refitted after break-in, break-in began from the low load when loading and continuous operation.
Cannot be repaired ⑦ cylinder accident or when not allowed to fix, take the cylinders approach continues to run.
Four, diesel engine knocking
1, knocking phenomenon
Diesel engines have a rule at run time is not normal or abnormal sound of knocking, a phenomenon known as knocking.
2, knocking causes
(1) causes combustion knocking
① premature fuel injection timing, average increase in pressure growth and maximum explosion pressure;
② the injector nozzle needle valve is stuck in the open position of oil spills;
③ Injector spring break and oil spills;
④ Injector spring loose, Kai valve pressure drops, spray oil in advance;
⑤ overstretched the cylinder, fuel injection quantity is too large;
⑥ the poor combustion of the fuel, ignition delay.
(2) causes of mechanical knocking
Pneumatic cylinder upper mechanical knocking causes are:
① first came across the upper part of the cylinder liner wear of piston rings;
② the centerline of piston connecting rod and the crankshaft centre line is not vertical, the piston to a tilt movements;
③ slap caused by eccentric wear of crank pin bearings.
Central mechanical knocking cylinder causes are:
① four-stroke diesel engine piston pin clearance is too large;
② the four-stroke diesel engine piston and cylinder gap is too large;
③ severe wear of the cylinder liner.
Cylinder lower mechanical knocking causes are:
① crosshead bearing clearance is too large;
② cross head slider and guide clearance is too large;
③ connecting rod bearing or bearing clearance is too large;
④ the main moving parts of the bolt.
3, knocking of emergency treatment
① to pressure test the injectors and adjust them if necessary to get a new;
② Check fuel pump fuel delivery and, if necessary, to adjust their effective travel;
③ check and adjust the fuel injection timing.
Five, diesel engines scavenging box fire
1, scavenging box fire causes
Scavenging box fire must have two conditions: first, scavenge boxes within the accumulation of large amounts of fuel; the second is a high temperature
Ignition source exists.
2, scavenging box ignition and preventive measures
Sweep gas box fire, its phenomenon performance for row smoke temperature increased, and sweep temperatures degrees improve, and chimney risk black smoke, and sweep gas box overheating, and open sweep gas box placed release cock check Shi has smoke or sparks spray out; diesel engine speed automatically declined; and the cylinder connected of booster Manager occurs asthma vibration; sweep gas box fire Shi due to pressure temperature sharp rise occurs sweep gas box explosion makes safety valve takeoff.
Preventive measures include:
① Open the relief valve scavenging box on a regular basis, residual oil drain;
② periodically check the clean sweep gas space and avoid accumulating too much oil scavenge space;
③ in part load, reduce the amount of oil cylinder injection;
④ control the sweep of normal temperature;
⑤ to avoid long periods of low-speed running, will result in bad Burns;
⑥ avoid overload operation, overload increased wear and tear and gas leaks;
⑦ When a big storm reduced engine speed to avoid loading mutations range is too large;
⑧ the correct adjustment of atomization of the fuel injector status;
Issues fuel injector fuel injection timing correctly;
⑩ periodically checks the status of piston rings, piston rings to wear, break up and stick replaced in a timely manner.
3, scavenging box ignition of emergency treatment
① first of all reduce the speed of the diesel engine, ignition cylinder and cut off the fuel supply;
② If the fire was serious, you can slow down or stop immediately, extinguishing measures taken;
③ steam fire or carbon dioxide fire extinguishing;
④ Jet sweeps the air box shell with warm water, if necessary, reduce the temperature;
⑤ ignition cylinder due to increase of volume of lube oil, ensure adequate lubrication within cylinders;
⑥ should stop checking the fire has gone out.
Six, diesel engine crankcase explosion
1, crankcase explosion causes
① become deflagration within the crankcase oil mist concentration mixing ratio are basic requirements for explosion;
② high-temperature heat source exists are decisive factors in the explosion.
2, crankcase explosion prevention
① to avoid heat sources in the diesel engine;
② installed oil mist concentration detector in diesel engine;
③ take crankcase, ventilation;
④ on the exhaust side of the crankcase cover fitted with explosion-proof door.
3, emergency treatment
① If there is signs of explosion hazard, should immediately stop running or spin down, spin down after generator should load conversion games
Line. If the generator stopped, comes with lubricating oil pump and cooling water pump will stop, but easy to just stop crankcase explosion occurred.
② When they discover a crankcase explosion dangerous during the cabin crew are not allowed in the side of diesel engines fitted with explosion-proof door stop
To avoid casualties.
③ When the explosion occurred in the crankcase and explosion-proof valve after sitting, to take immediate measures, but not immediately opening song
Axle box door or manhole fire.
④ If due to certain parts of the crankcase heating, parking, parking 15min at least, and then clear the door checking to avoid fresh air
After tank exploded.
⑤ fire extinguishing installation within the crankcase on the crank shaft tube into which carbon dioxide of carbon dioxide.
Seven, diesel engine chimneys sparkling
1, chimney sparkling causes
① oil mist formed by combustion sparks;
② oil residue formed by combustion of sparks;
③ soot formed by sediment burning sparks.
2 prevention measures, chimney, sparkling
① keep in-cylinder combustion in diesel engine in good condition;
② strengthened cylinder combustion process monitoring, timely detection of irregularities;
③ strengthening the management of exhaust boiler, maintains good combustion results;
④ to select proper carbon removal by chemicals such as agent;
⑤ to guarantee the safety of oil tankers, chimney equipped with sprinkler devices, preventing chimney sparkling.
3, emergency treatment
① If there is spark in this category, should immediately reduce the load of diesel engines or slowly stop;
② If this class two or three sparks in environmental conditions should be allowed to continue "blowing risk", in the exhaust system
Oily sediments blow out as much as possible, burn.
③ do not use fire-fighting equipment easily, particularly carbon dioxide fire extinguishing equipment in order to prevent high-temperature metal explosion due to temperature sharply reduced.
Eight, diesel engine connecting-rod bolt fracture
1, check of the connecting rod bolts
① check for defects using a magnifying glass or the naked eye, especially check the bolt head, rib and rib root.
② tooth gauge and ruler check the pitch and bending of rib.
③ nut loaded, see if its too loose to check the wear of ribbing, especially to check the nut and bolt head and
Bearing contact surface is uniform contact lamination is good.
④ bolts with wire rope hanging together, Bishop beat, with new bolts compared their sound to identify the defect-free and
Degree of fatigue.
⑤ bolts on the bearing, loose in the following two and a half hole for Fay, bearing cap displacement due to centrifugal force, will enable
Bolts subjected to shearing force role. If upper and lower bearing joints exposed hundreds of alloys, when a bolt is installed it to find, or Burr hole edge, easy to make bolt bitten to death.
⑥ check connecting rod bolt and bolt hole clearance, not too tight.
⑦ check whether the PIN is loose or worn.
⑧ tightening nut when you insert a split pin, split pin is contact with the upper surface of the nut should be checked.
Issues measure the total length of the connecting rod bolt to check its elongation.
⑩ medium following the life of a four-stroke engine connecting rod bolts about 15 000~20 000 hours. Over this time,
Even though the appearance is also should be renewed.
Considerations 2, tighten the connecting rod bolt
① You must keep the gasket and bearing joint surface clean, ensuring their full access.
② General almost no tightening bolts fastening State of insufficient, excessive ground bolts to fatigue, is not secure.
③ on either side of the connecting rod bolt must alternate
