Saturday, March 29, 2014

Boiler Back fire: Possible causes


Boiler Back fire

Possible Causes of Boiler Backfire.
? Improper tuning of the burner
? Accumulation of un burnt fuel left in the furnace
? Air Fuel ratio disturbance
? Outlet damper partially/fully closed
? Purging time before and after burner shut off not enough i.e. too short
? Flue gases outlet damper malfunction
? High flow from FD
? Low rpm of ID fan

? Repeated unsuccessful start attempts for boiler firing

Monday, March 24, 2014

Sensible Heating & Sensible Cooling

Sensible Heating & Sensible Cooling


Sensible Heating: The heating of air without the change of Specific Humidity is  called sensible heating.




Sensible Cooling: The Cooling of air without the change of Specific Humidity is  called sensible heating.

INTERNAL MEASURING INSTRUMENT CALIBRATION

INTERNAL MEASURING INSTRUMENT CALIBRATION

The measuring instruments such as Weighing Scale, Thermometer, Hygrometer etc calibration is very important in industrial areas. The local standard testing institution have the facility to calibrate these instruments. But on a large scale quantity it is expensive to calibrated the instruments from the testing institution. So there could be used the instrument which is calibrated from the testing institution as Master Copy. On every machine the allowable deviation data is given, so after calibration if found more deviation then instruments need to be repaired/Serviced. 
For calibrating weighing scale the methods can be followed:
> Take the numbers of Master/reference standard weight and observed the weight in the weighing scale
> Take  series of  data
> Record the observed  data 
> Find the deviation
For calibrating Thermometer the methods can be followed: 
> Take the  Master/reference standard Thermometer and observed the temperature in the thermometer
> Take series of  data
> Record the observed  data
> Find the deviation
For calibrating Hygrometer the methods can be followed:
> Take the  Master/reference standard Thermometer and observed the temperature in the thermometer
> Take series of  data
> Record the observed  data
> Find the Relative Humidity from the Psychometric Chart
> Find the deviation