Induced Draft Fan

INDUCED DRAFT FAN

RITESH KUMAR CONSTRUCTION , M6K221 MECHANICAL ENGGINEER

Reference : “shaft alignment hand book", ‘john piotrowski’.

DRAFT SYSTEM



Supply air for combustion



Remove air from furnace



Transporting pulverized coal to furnace



Maintain speed for heat transfer

DRAFT SYSTEM



Supply air for combustion



Remove air from furnace



Transporting pulverized coal to furnace



Maintain speed for heat transfer

DRAFT SYSTEM

TYPES OF FANS Axial fan

Centrifugal fan



Fluid comes axially .



Fluid comes axially.



Get compressed while moving axial.



Get compressed because of  centrifugal action.



Move out axially.



Comes out of fan radially.

CENRIFUGAL FANS

ERECTION OF INDUCED DRAFT FANS 

Blue matching



Erection of packer plates



Primary alignment



Secondary alignments



Inlet cone erection



Erection of casing

Blue matching of machine foot , wedge plates and packer plates is done

Leveling device

Packer plate

Erection of packer plate 

Elevation



Flatness



Co planarity



positioning

Master level

Installation of induced draft fan

Result of improper installation 

Lose of production



Premature failure of machine components



Loss of energy

To insure ,before alignment some primary checks are done

Preliminary checks 

Coupling half runout



Soft footing



Bearing

Runout check  Runout standards

 Maximum times these standards are provided by manufacturer 

Shaft speed

Maximum runout

0-1800 rpm

0.13 mm

1800-3600 rpm

0.08 mm

3600+ rpm

0.05 mm

Ways of detecting soft foot Dial indicator

shims