During boiler operation, if the furnace worker does not operate according to the instructions in the operation or lack responsibility, it can cause serious damage to the boiler parts or cause accidents. for the workers to burn the furnace… it is called a boiler failure.
During boiler operation, if the furnace worker does not operate according to the instructions in the operation or lack responsibility, it can cause serious damage to the boiler parts or cause accidents. for the workers to burn the furnace… it is called a boiler failure.
In this section we will introduce some typical problems commonly found in boilers, all problems are presented in 3 parts:
- Manipulation of troubleshooting
In production practice, there may be more special problems, more complicated than the ones mentioned here, then require the boiler operator to calmly listen, verify the phenomena, judge the causes. to have troubleshooting actions in a timely and accurate manner.
1 - Excessive dehydration
During the boiler operation, suddenly the furnace worker saw that the water tube was no longer water, could not see the line between half white and shiny black half, but saw that the tube was just a white color of steam.
At the same time, there may be a slight increase in the manometer needle, if the pressure increases too specified, a fart sound can be heard in the safety valve.
If you open the door for coal, the fire in the furnace burns intensely, the furnace walls of the chamber burn hotter than usual
- Due to the negligence of the furnace worker, forgetting to regularly monitor the water level in the water pipe, forgetting to supply water for the boiler.
- Due to the fact that the boiler blowdown valve is open, leaking, leaking a lot, the water level on the water pipe drops quickly without seeing.
- Because the boiler has a part of broken (cracked) water escaping without knowing (often broken in the ball of the steam generator, manifold, screen ...)
- Due to the failure of the pump or the "circulating valve" in the wrong position, even though the pump is running, but water is not entering the boiler, the operator does not pay attention to the water pipe.
- Due to clogged plumbing, or vacuum pump (centrifugal pump), water does not enter the boiler.
- It should also be noted that there is a phenomenon of "artificial water loss", ie the water pipes, steam venting to the water pipe are blocked, after the discharge of the water pipe is finished, there is no water left in the water pipe when the pipe is added. The water in the boiler is working again, actually the water in the boiler is enough to normal level, but there is the opposite situation: also because the water pipes, the steam pipes to the water pipe are blocked, but the actual water level in the boiler has been blocked. it was too low, but the water level in the water pipe was still high, which was a very dangerous case. To overcome the fake water residue, furnace workers must look at the water level in the water pipe and often see the water surface in the water pipe vibrate, up and down a little, when the water surface in the water tube is standing still for a long time. The actual boiler water level should be checked by clearing the water tube.
- Firstly, to carefully examine whether the water pipe is running or not, then check the water level by "calling water", as follows:
+ Tightly close the vent valve, vent the water to the water pipe
+ Open the bottom discharge valve of the water pipe to let the steam escape, the water in the water pipe drains out, then quickly close the water pipe bottom discharge valve.
+ Slowly open the water valve
If there is still water in the bottom glass of the water tube and it is still possible to supply additional water to the boiler, the furnace worker will continue as follows:
+ Immediately turn off the boiler fan, smoke fan, close the wind shields in the oven underneath.
+ Run the water supply pump into the boiler, when you open the valve to allow water to flow into the boiler, slowly, be careful, listen for noises inside the furnace, pay attention to the water level in the water pipe.
+ If there is no unusual phenomenon, continue supplying water to the lowest level of the water pipe (below specified line), turn off the pump, stop supplying water to the boiler. Then for about 5 minutes continue (open) run the water supply pump into the boiler up to the average of the water pipe.
If you have checked the water level in the boiler by calling water twice and still do not see the water level at the bottom of the water pipe, you must open the water level check taps at the bottom of the water pipe. boiler (open the bottom tap first, then the middle tap), if there is no longer any water tap, quickly stop the boiler, absolutely do not supply water to the boiler.
If you turn on the water absorbent tap to show water, you must check the light again (because the bottom tap is located a little higher than the bottom of the water pipe but there is still water, which indicates that the water hose is damaged). water tube.
Operation stops the oven when a serious water dryness occurs
- Close the wind door, turn off the fan
- Rake ash and slag out of the record, or speed up the chain to put ash and slag into the ash box
- Close the valve to supply steam to production
- Turn on the fan to suck smoke out of the boiler
- Close the doors for coal, the ash rake doors on the two sides of the furnace ... to let the boiler cool down, it is absolutely forbidden to supply cold water into the boiler during the process of troubleshooting.
- Keep the scene and make a record
2 - The water is too full
- Often see the water completely covered the water pipe, the entire body of the water tube is a shiny white color
- It is possible to see the pressure of the boiler slowly drop at the same time (the manometer needle gradually drops)
- If the boiler supplies steam to easily detectable steam consuming areas such as turbines, steam mixture drying, there will be abnormal phenomenon in places where steam is consumed.
- Due to the boiler operator negligently, do not pay attention to the water level of the water pipe while taking water into the boiler, forget to turn off the water supply plate, when the boiler has enough water.
- The boiler water supply valve has a big leak, when another boiler gets water (installing a common water pipe), the water goes through the damaged water supply valve and flows into the boiler until it's full. do not know too.
- Note, there are times when the water is completely flooded (after discharging the water pipe, let the water pipe work again), but it is not a water problem, overfilled, but because the steam pipe to the water pipe is irritated. The water in the boiler overflowed to raise the water pipes. In this case, you must carefully check the actual water level of the boiler with the water level check hose (dark water pipe) from the top (usually there are 2,3 taps near the water-light pipe system) and pay attention to the pressure needle. Is the next step down?
On the contrary, there are times when the water in the boiler is full, but the water level in the water pipe is still normal, it is because the water pipe through the water pipe is clogged, in this case, the water level in the water tube is usually standing still. vibrating, up and down
- First, if water is being supplied to the boiler, immediately turn off the pump and lock the water supply valve.
- Check the water pipe, clear the water pipe, then let it work again. If the water level is still closed, check the dark water level. If you find that it matches the water level of the water-light pipe, quickly do the following:
+ Drain the pot bottom drain valve, rinse each time until the water level of the water pipe is at the highest level, the discharge will stop.
+ After 3 minutes, it will continue to drain the water level in the boiler down to the normal level.
- If the steam supplied to the steam consumer requires the quality of the steam to be dry: running a steam turbine, drying food ... it may be necessary to close the main steam valve, stop supplying steam to production, vent to the outdoors. or channel the safety valve to let the steam escape.
When the water level is stable, at normal level and the steam quality is good, then open the main valve supplying steam to production, lower the safety valve or close the steam valve.
3- The manometer is broken
Manometers often fail with the following phenomena:
- The manometer glass is cracked or broken
- The manometer needle does not return to "0" when the pressure in the manometer has been discharged
- Tet at the foot of the manometer is strongly deflated, making the manometer work incorrectly
- Manometer is only wrong, not with sample manometer
- The manometer is vibrated while working
- The glass is blurred, the gauge of the manometer cannot be seen
b) Causes and handling operations:
- The manometer glass is broken (cracked or broken) due to the following reasons:
Because the manometer is hot, cold water is suddenly sprayed directly onto the glass
+ Due to being hit hard against the glass surface by something such as the top of the ladder, bricks and tiles fall from the door, pliers, and wrench when workers repair the boiler.
+ Because the compression frame on the glass of the manometer is too stretch, when it is hot, it expands, so it is added to the glass, often causing the glass to crack
If the manometer glass is slightly damaged, the glass does not come out of the support frame, does not have a large opening, the manometer is working normally, but the failure of this manometer should be recorded in the boiler operation log. Shift handover book so that when the oven is stopped, the manometer will replace or repair this manometer.
If the glass is badly damaged: break open, completely drop the glass out, or have the glass on the manometer, but interfere with the manometer needle's working, then another manometer must be replaced. The procedure for changing manometer is as follows:
+ Turn the 3-way valve in the direction of locking the steam to the manometer, let the steam escape outdoors, then turn the valve at 3 ways toward the discharge of stagnant water from the manometer out, finally turn the 3 valve back to the direction of the lock. steam line from the boiler to the manometer and to the 3-way flange (you can turn the hand wheel slightly away, or leave it in the discharge position to close the manometer outside).
+ Remove the old manometer very carefully, replace the braid or washers and install a new one.
+ Turn the 3-way valve to get a little steam from the boiler to dry a new manometer, after 1.2 minutes to open all the hand to smooth steam from the manometer boiler, and let the manometer work, continue to listen for half hours after replacing the manometer.
If the manometer is badly damaged and there is no good manometer to replace, the oven must be stopped (normally allowed to stop the oven) even in the case where the steam is consumed with a good manometer, the boiler must be stopped.
- The manometer needle does not return to "0" when the manometer has been exhausted, there are two reasons: one is because the 3-way valve is blocked, the vent is deflected so that the hydrometer does not escape. . The second is due to the damaged internal part of the manometer (usually: tangled hair, notched teeth of the needle shaft and rotating frame, channeling, broken teeth, colon of the colon ...)
When the manometer needle does not return to "0" but due to failure of the valve 3 or the failure of the manometer, the oven must be stopped to replace a new manometer. Unless a stop valve is installed on the steam pipe connecting the boiler to the manometer, in this case it is possible to lock the valve tightly to change the manometer, replace the 3-way valve well, but be sure that the stop valve is good and tight. new repair and replacement.
- Tet or the gasket in the manometer leg is deflated strongly, making the manometer work incorrectly. The reason is that the new one or the gaskets used for a long time has been rotten, damaged, the manometer is slightly leaking out, the pressure is slightly lower than the actual pressure of the boiler. When seeing such phenomenon, the boiler workers must replace, the gasket of the manometer, and behave like when replacing the new manometer (turn the 3 valve back to the direction of locking the steam from the boiler, wait for the old manometer to cool down slightly. braided or gasket on the manometer leg, when working, it is necessary to have gloves and goggles).
- Manometer is only wrong with sample manometer
Usually due to two reasons: one is due to the failure of the 3-way valve (the vent in the intestine and the body of the valve are not connected, the steam through which the manometer is reduced in pressure), the other is due to the failure of the internal part of the gage. damage: hair (creak) is tangled, broken teeth or channel, brake screws, adjustment screws are loosened ... Sometimes, because the needle is rotated and slipped with the needle holder. All these failures can lead to the safety problems of the boiler.
Therefore, if the boiler manometer "deviates slightly" than the sample manometer 0.5 kg / cm2, it is allowed to use it until the most recent repair period, but not more than 3 months.
If the differential manometer is heavier than the sample manometer, or lighter than the normal furnace to replace or repair the 3-way valve).
Note: The 0.5 kg / cm2 clogged “slight deviation” is 0.5 kg / cm2 of the boiler manometer reading than the sample manometer, usually referred to as the gauge is lighter than the sample manometer.
- The manometer needle is strongly vibrated
This is usually due to a damaged gut part (expansion tube) inside the manometer. If the vibration amplitude of the needle exceeds ± 0.5 kg / cm2, a good, new manometer must be replaced. If the oscillation amplitude of the needle is £ 0.5kg / cm2, this manometer is allowed to use up to the most recent repair period, but not more than 3 months.
- The glass is blurred
The gauge of the manometer cannot be seen, usually for the following reasons:
+ The outside of the glass is covered by smoke from the oven, in this case, it is necessary to regularly return to birth and clean the glass.
+ If there is a slight leak in the plait of the manometer, leaking into the inside of the manometer (when the manometer cover is not tight) opens the inside of the glass, in this case, open the glass of the manometer to clean, must use gloves and protective glasses. When removing the manometer glass, it must be repaired and replaced with a plait. If the manometer has a lead seal, when removing the lead to open the manometer, it is required to make a record and report it to the workshop comrade in charge of the workshop, record this issue in the operation book or the boiler shift book.
+ Curved and expanded tube (chicken gut) inside the manometer is deflated at the tube body or the weld joint, causing evaporation to cover the manometer glass. In this case, another manometer must be replaced.
During manometer replacement and repair, furnace repair and furnace workers must pay close attention to the water level in the water pipe, which is usually above average.
4 - The water pipe is cracked or broken
The boiler was working, suddenly heard the sound of glass cracking, then saw water and steam leaking from the glass tube, sometimes the manometer needle fluctuated slightly.
If the water tube is severely broken, an explosion can be heard and then there is a very strong water and steam leaking out of the tube, the manometer needle drops a little, the whole boiler is covered in steam.
- The water pipe gets hot and cold suddenly: when the boiler is working, the furnace house is open, rain water is splashed into the water pipe, the sanitary water accidentally sprayed directly into the water pipe, it takes a long time to clear the water pipe. The water tube should be re-operated but not slightly opened to preheat it for 1.2 minutes.
- By tightening the braid sealing rings at the two ends of the water pipe, the water tube body (for flat water pipes), when working, the water pipe is expanded, these washers tighten the expansion water pipe so that it cannot crack. .
- Due to the poor quality of the glass panels, the glass pipes (glass tubes), the glass is not temperature and pressure resistant, the glass breaks when hot.
- Due to strong impact on the glass surface ...
- Be careful and urgently close the water venting valve, vent to the water pipe, to prevent damage, use gloves, glasses, boots and other necessary equipment.
- Replace the new water pipe, the operation sequence is as follows:
+ Check carefully whether the exhaust valve is fully open, the vent valves, water venting to the water pipe are closed properly.
+ If it is a flat glass-type water tube, open the bolts and bolts between the surface of the water pipe one by one, take the new glass to replace it, replace the gaskets at the edge of the glass surface, tighten the bolts, bolts to compress the face. glass inlet lens. Re-use the caps that keep the body of the tube so that the whole body of the tube is closed and straight. It is also possible to open the caps, and take the whole water tube down, complete the treatment, install 2 caps to keep the two ends of the water tube.
+ If it is a round water tube, it is necessary to open the cap caps (sprinkle - shrink) to hold the two ends of the water tube, replace the braids, replace the new water tube, tighten the caps for the stable water tube, pay attention to rotate the tube When tightening on all sides, just start tightening 2 caps, to prevent the glass tube from being deviated, when tightening 2 caps, the glass tube will be broken.
+ After replacing the new water pipe, it must be slowly, cautiously shout to open the steam valve a little to dry the water pipe for at least 2 minutes, then let the water pipe work again, according to the operating order stated in the above. section 1.2
Note: in the process of curing, replacing the water pipe, make sure the water level is above average. If you find that there is a lot of water before, you must add water to the boiler or limit the supply of steam for production.
- If there is no replacement water pipe, it is necessary to stop the oven for fault. In case the boiler has 2 light-water tubes and a water level control tap system (dark water tube), it is possible to allow the boiler to work temporarily to continue working period.
- Sometimes, due to improper repairing techniques, especially when welding and welding parts are required to cause deformations affecting other parts (such as sieve welding affecting the edges of cyclones, welding near metal edge - the canopy affects the welded studs near the gasket support edge causing the gasket support to warp, not tight ...)
- Because the bending effects have cyclic fluctuations, making the metal in those places work "tired" easily cause cracking.
The fracture phenomenon of the pressure parts, whether big or small, in the main or non-major parts, inside or outside the boiler, must stop the boiler to prevent the damaging damage. workers and equipment.
5 - Dirty drain valve is damaged
- After the dirty discharge is complete, close the drain valve and see that there is still water leakage at the end of the exhaust pipe, the entire exhaust after the exhaust valve is continuously hot.
If the leak is heavy, the water drains strongly and the manometer needle drops relatively quickly.
- Because the lid is worn out when closed, the lid is not tight, steam according to the gap leak out (cause slight damage)
- Due to the lid being channeled by layers of hard residue or channel by something left over in the boiler when the boiler was repaired, water escaped relatively much (causing serious damage).
- Sometimes, because the screw of the valve is broken, causing the cap to close the air or the channel completely onto the valve cap support, without closing any more.
- Check the exhaust valve again by opening the valve up and down tightly (with bare hands), if you find that the drain valve is still leaking strongly, you must immediately close the stop valve (close the boiler) and close the exhaust valve. sounds hot for a while. If the water still drains out continuously, quickly run additional water pump into the boiler and stop the boiler down. In the process of lowering the temperature, pay attention to pump additional water into the boiler, keeping the water level in the boiler always above average.
- If it is clear that only one external drain valve is damaged, the inner stopper can be closed tightly, repaired or replaced, then let these two valves work again and see if it is good for the boiler. work again as usual, but pay extra attention to prevent any damage.
6 - The water supply valve assembly is damaged
The water supply valve cluster consists of a stop valve (also known as an interlock valve) and a 1-way valve (also known as a return valve), a 1-way valve fitted close to the boiler.
When this valve assembly is damaged, it often causes the steam in the cooker to leak back to the water supply pump through the water supply system. When this pipeline is at rest, the two valves are closed but still the pipe is hot.
- When the boiler was working together in the water supply system, the boiler water level kept rising (although the water supply valves were closed) when the other boilers took water, because water leaked through these valves into the boiler. That slightly.
- There are times when the water pump does not enter the boiler even though the connection valve is fully open.
- During the process of this valve assembly, water flows through the cover and cap support of the valve (flag - flap - peep - and xi - e - valve), in the water there are impurities, soil and sand, erosion of the cover and base. valve cover, so when fully closed, the valve assembly still does not seal.
- Sometimes, because the water is not filtered well, the cover of the valve, when closed, entangles with hard objects such as gravel, warping the valve cap, not closed tightly.
- The automatic closing cap of the non-return valve is stuck hard and cannot be lowered (stuck between the valve shaft with the retention hole and the shaft direction) if water can leak through the cover of the non-return valve.
If the stopper of the hard-jammed check valve cannot be lifted, even though the pump is running, the connection valve is open, but water does not enter the boiler.
The failure of the water supply valve assembly often leads to serious consequences:
+ If the pump runs out of valve failure, water can not enter, it will easily cause a serious drain without knowing it.
+ If the pump runs, the valve closes tightly (to get water into another furnace) and the water still enters the boiler, it is easy to cause an accident of overfilling without knowing it.
+ If the boiler is working, the valve is closed tightly and the water and steam still leak back into the pipe, the water supply pump is very easy to damage the pump (because the feed water temperature is over 50oC, the expansion impeller can close to the pump housing) or cause burns to the pump operator when the pump seal is broken, or cause repairs, water pipes, water valves, flanges to explode first, encounter many problems and no safe
- If this valve assembly is leaking slightly, it is possible to temporarily let the boiler work until the nearest repair period, but not more than 1 month, and must take measures to protect the water supply pump. damaged due to overheating of water, by occasionally discharging the hot water that is left in the water supply system and in the pump out, the gas has to repair parts of the piping system or the water supply pump, the remaining water must be drained. repaired in the out tube.
- If this valve assembly is badly damaged, steam leaks out very strongly or vice versa, pumping water does not enter ... it is necessary to stop the oven for trouble.
7 - Burn the oven stuck or broken
+ For automatic chainring, the following phenomena usually occur;
- The furnace in motion suddenly stops, the middle part of the furnace is overheated, if stopped for a long time, this burner may burn and cause deformation in other parts of the burner.
- The burner is in normal motion, suddenly it moves abnormally when fast, slow down, sometimes stop for a bit and then run again.
+ For manual recording. The following symptoms usually occur:
- Failure to flip and shake (commonly found in fire tube boilers, Bun - gas - ri, train oil ...) when the furnace is finished, peeling or shaking the ash to fall under the furnace, when the burner is closed. no more balance, the burner surface of the flip-chart, there is a gap in the burner, the roll is drenched in that area, the coal will fall under the furnace through that space.
- Static recording failure - when the furnace is working, there is a drop of coal on the burner, the burn and half-burned coal fell to the bottom of the kiln, sometimes only the ring deformation furnace has not been broken and fell completely under the furnace.
The main cause of burning, breaking, jamming (types) is due to improper use of the air in the combustion chamber, the supply of too little wind, making the underside not recording in accordance with regulations, providing too little wind causes the underside of the recorder not to lose in time, overheat causing fire, broken track, if the chain track falls on the chain wheel, it will cause the recording to stop running.
For swing and flip recorders, in addition to cause and heat can also be caused by mechanical causes such as failure of the pin (flag - out - vet), the tipping wheel, the jigger, or the wear on the reel holder. It is too wide when closed and closed, the recording does not match the old one, the channel is up or not to the horizontal surface.
Also due to the following reasons:
- Using iron sticks, scraping too heavy iron to throw at the recording surface, it breaks or crack.
- Fabrication of furnace with cast iron too bad to withstand high temperatures
- Due to the damaged recording surface support losing a recording reaper or some registers
+ For chain grate
- If some of the plate is burned without causing the recording jam, cover the recording surface with more coal (increase the clearance of the coal adjustment plate), maintain the fan evenly and at a relatively large level, let the recorder run from From the moment you see a fault at the burner check door, will stop recording, quickly replace the damaged blades absolutely forbid turn off the fan in the oven when the burner is stopped, because in doing so the oven will be overheating and causing serious malfunction on the entire burner face.
- If for some reason the furnace is closed, then write the furnace back to a 2m section, then run the furnace back to normal direction, if the furnace moves, just carefully check the recording surface. If a few leaves burn, then replace as just mentioned above.
If the burner cannot work backwards or backwards, but when going down the burner, it will get stuck, absolutely must stop the boiler.
For manual burning static recording
- When the recorder is broken, the recorder must be stopped to repair the faulty recording.
- When broken (broken, hammock) the static recordings: the plate or bar can be beaten with iron bars, tie new records with rope to the right place to replace the record, the wire is burned, the record will be in the correct position. How to burn damaged. The items that have sagged down even though they have not been broken must also be replaced with other items like the method just mentioned above.
Note: In the process of changing the manual record, you must open all the air inlets in the undercarriage, limit the door to coal, absolutely prohibit running fans when changing the recording, because it is easy to cause accidents to repair workers.
8 - Dropping the wall, rolling the oven, broken the insulation in the oven
- When the wall or coil of the furnace falls, you can hear unusual noises in the fire chamber, the smoke channel, and at the same time you see the fire and smoke flowing out the door for coal, depending on how much or how little the wall drops, the fire will come out long or short. If the furnace wall falls down without being detected in time, it can cause serious cracking of the furnace wall, red fire of boiler frames, etc.
- When the insulation is damaged, it is necessary to check that by means of the inspection doors, asbestos fibers for insulation can be seen in the corners of the furnace wall, or between the furnace wall and the heating surfaces being thrown out or sagged. It is common to see bricks, asbestos fibers that insulate the bottom discharge pipes (located in the boiler) or the insulation bricks for the boiler racks are leaking, in the racks.
Mainly due to the improper construction and installation: to make the brick circuit too wide (over 3mm), the refractory brick mortar chose the wrong formula, the shape brick built the furnace rolls not in the right shape of the furnace design ...
- Due to the failure of objects to keep, remove the wall, the roller is damaged, causing the rolling wall to fall.
- Because the expansion parts in the boiler are not free, the rolling walls are replaced.
- Because bricks and insulation substances (asbestos fiber, sheet asbestos) are too old, have been damp many times when repaired, and have not yet been replaced with new materials.
- If the wall of the furnace has a slight drop in insulation, which does not reveal metal frames, shelves, supports, etc., the smoke drains run and there is no danger of cracking the outside furnace wall, then it is allowed. the working furnace continues to the nearest repair period, but not more than 1 month.
- If the wall, coil of the furnace, the insulation parts are plunged heavily, obstructing the escape of smoke in the boiler, causing the boiler frames, rack and base to become red hot, the boiler must be stopped to fix the problem. cure.
9 - Fire and explosion in smoke ditches
- Seeing fire, sometimes there is an explosion in the smoke ditch (from the boiler to the chimney), breaking the insurance films in the smoke ditch, flipping the covers of the ash containers (weighing 30-40kg) even If the fire is large, it will cause a fire there.
- Seeing the fire and smoke gushing out the door for coal, sometimes knocking the door lock for coal
Then the whole furnace was covered with dust, the burning of fuel gradually decreased, the steam pressure dropped.
Because during the combustion process, the fuel has not been completely burned, the smoke out of the boiler still contains a large amount of CO and other flammable gases, when the smoke temperature suddenly increases (over 250oC) and the escape is met. obstacles, such as part of the chimney filled with ash or rain making it difficult for smoke to escape ... then in the ditch, burning parts of the remaining fuel will occur and cause an explosion, depending on the mixing ratio. Combining flammable gases and oxygen these reactions cause a strong or weak explosion. When the volume explodes increases, the pressure on the smoke raceways increases will cause the phenomena mentioned above
- If the fire is small, does not cause collapse of the smoke channel, does not obstruct the smoke escape ... then quickly turn off the fan, the undercarriage inlets will be closed tightly, cover the lid in the smoke ditch. Out, find the insulation, seal in the protective film. If there is a fire out, it must be repaired immediately with fire protection equipment, when the oven is back to normal, slowly open the fan to check, check the phenomenon, if there is no new problem for the pot. Steam work continues.
- If there is a big fire or explosion, the smoke ditch bursts, it is necessary to stop the furnace and prevent a fire in the furnace.
10 - The boiler fan or pump is damaged
- Most commonly when the pump is pressed, the fan does not see the fan pump running.
- The fan pump is running, but there is not enough water or wind to supply the boiler.
- Fan pump running abnormally: Speed is slow, loud, hot in the shaft supports (temperature over 60oC)
- push the start button and the pump or fan is not running because: the power to the motor loses 1 phase, or between the rotating part (the rotor) and the stationary part (stator) of the electric motor close together, or the windings of the motor pulling the pump, the fan is fire due to roaring before running without check the insulation.
- The fan pump is running, but there is not enough water, the wind supplied to the boiler is due to: the impeller, damaged: broken, too worn ... or due to the insufficient speed: slip belt
Must immediately cut off the power, stop the fan, stop the pump, notify the electrician, mechanic to repair, absolutely forbid energizing, inserting, times or taking anything to insert the contacts to insert the push button to start testing the pump. the room is in good working order to be ready to supply water when needed.
During the operation of the boiler, there are also other problems and failures, but it is not common in the boilers such as lead "drop", failure of boiler, water heater - should be This is not an introduction, but mentioned in the structural parts of those parts.
11 Steam pipe breakdown and emergency measures
a. Phenomenon when a steam pipe failure occurs
1) The water level in the water pipe drops quickly
2) slightly lower pressure
3) The readings on the water flow meter and the flow meter are slightly different (high water flow, slightly less flow).
4) In the combustion chamber or in the smoke line there is a loud noise and a strong thump (the sound is a gas).
5) The flame in the combustion chamber turns grayish pink or sometimes completely extinguished. The capacity of the boiler is lowered
6) From control doors and crevices there is smoke and steam gushing out
7) The ash from the funnel gets wet.
b. Handling measures when the tube is slightly broken, not to stop burning
When there is little water flow in the whirl openings of the wall-jointed water pipe, the water heater tube, the steam dryer pipe, the thermostat pipe, or small cracks in the aforementioned pipes and welds, it is also necessary to burning break. In the case of a slight rupture of the tube, that is, if the steam tube or pot water is only slightly damaged, the water flow or deflation is not serious, the problem does not tend to grow rapidly, the water level in the pot can hold. be in the normal range. Thus the boiler does not have to stop burning immediately, but reduce the capacity of the boiler, and then continue to operate until the spare boiler is burned for replacement. After that, it was necessary to stop burning the pot and caused problems. When it is found that there is a minor problem in the boiler, specific measures will be taken as follows:
1) Moderately reduce the amount of evaporation of the pot, and continue to operate
2) Immediately report to the steam generator and report to the head shift to wait for a decision. 3) If the decision to stop the boiler has been received, the operating sequence is the same as for normal combustion.
If this problem arises, it is necessary to contact the steam unit and obtain approval from the technical leadership of the plant to stop burning.
c. Emergency response when the steam pipe or water cracks seriously affect the water level in the boiler.
In case the boiler steam tube bursts but the boiler water level cannot be kept normally, the operation should be stopped immediately (stop the coal and blower to the furnace, and the water must continue for a while). . The specific procedure is as follows:
1) Immediately stop the spray nozzle, or stop putting coal in the blower. Turn off the fire in the oven immediately