Facts worth knowing about Oil nozzles - Danfoss.com

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What is the cause of no oil from the nozzle?To say the least, it is irritating if not one drop of oil emerges from thenozzle. To eliminate the cause, follow the step-by-step approach below.• Is there oil in the tank.• Is the valve on the suction line open or closed.• Is the check-valve on the suction line the wrong way round.• Does the pump rotate. Sometimes the pump/motor coupling can break up.• Does the pump suck. How much suction does the vacuum meter show.• Can the presence of air be seen in a transparent test hose on the suctionside of the pump. Air can enter because of too high a vacuum, or from aleak in the suction line.• Is the pump filter clean and in good order.• Are the pump hydraulic and solenoid valves open and working as theyshould be.• Is there dirt in the oil pipe to the nozzle.• Is the nozzle filter clean and in good order.• Is the nozzle blocked.• Is the oil very cold and thick. Perhaps some water in the oil has turned intoice.• Has the fire valve operated.If all these factors are checked and ordered as necessary there should nolonger be a problem.24
What causes oil coke on the nozzle and ignition electrodes?When liquid oil is heated above a certain temperature a process takes placecalled “cracking” and a stone-hard black carbon (coke) settles out. Undernormal operating conditions the amount of carbon deposited on the nozzleand ignition electrodes will be unnoticeable. But just a slight scratch on thetip of the nozzle can create a path along which small amounts of oil can findtheir way. This oil will not of course be atomized and will be exposed toradiant heat from the flame. Consequently, it will produce carbon on the tipof the nozzle and cause interference with the atomizing process and poorercombustion.The same thing can happen if the nozzle drips.If the ignition electrodes sit incorrectly they can form a projection for the oilspray to hit and any oil appearing on the tips of the electrodes will receiveheat from the flame and carbon deposits will start to build up.Eventually the electrodes will short circuit, the ignition spark will becomenon-existent and plant restart impossible.The tendency towards coking is worse on boilers with a heavy fire-bricklining. The reason is that fire-bricks give off strong return radiation whichwill reach oil particles on the nozzle, ignition electrodes and combustionhead during the periods when those parts are not being cooled down by airblast.Note!Coke formation on nozzle and electrodes will always lead to poorperformance and must at all costs be avoided.25
Page 1: Facts worth knowing aboutOil nozzle
Page 5 and 6: Oil nozzles and the complete oil-bu
Page 7 and 8: What has a Danfoss oil nozzle to of
Page 9 and 10: How does a Danfoss oil nozzle work?
Page 11 and 12: But how does the combustion itself
Page 13 and 14: What effect has atomizing pressure?
Page 15 and 16: What effect has air supply on the o
Page 17 and 18: Where must the oil nozzle be locate
Page 19 and 20: How should an oil nozzle be handled
Page 21 and 22: What do the numbers and letters on
Page 23 and 24: Is it possible to compare oil nozzl
Page 25: What makes the flame lopsided?A lop
Page 29 and 30: What produces a greasy malodorous d
Page 31 and 32: What causes the oil to ignite with
Page 33 and 34: What causes leakage between oil noz
Page 35 and 36: Can the nozzle cause too low a flue
Page 37 and 38: What causes oil and coke to collect
Page 39 and 40: What to do with old, worn out nozzl
Page 41: Nozzle capacitiesNozzle capacities

Facts worth knowing about Oil nozzles - Danfoss.com

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