Cochran Boiler

Presentation

1. COCHRAN BOILERCOCHRAN BOILER
By: AsayeDessie
2019

2. Outline
Introduction
Specification
Characteristics
Construction
Working principles
Mounting and accessories used
Maintenance
Advantage
Disadvantage
Reference
Introduction
Specification
Characteristics
Construction
Working principles
Mounting and accessories used
Maintenance
Advantage
Disadvantage
Reference

3. Introduction
Cochranboilerismodificationofsimpleverticalboilerwhere
heatingsurfacehasbeenincreasedbyincreasingnumbersof
firetubes.
Improvementoverthesimpleverticalboilerasitprovides
greaterheatingsurface.
Itisusedforsteamgenerationatlowrate.
Itisafiretubetypeboiler.
Itispopularportableboiler.
Itconsistofverysmallfloorarea.
Cochranboilerismodificationofsimpleverticalboilerwhere
heatingsurfacehasbeenincreasedbyincreasingnumbersof
firetubes.
Improvementoverthesimpleverticalboilerasitprovides
greaterheatingsurface.
Itisusedforsteamgenerationatlowrate.
Itisafiretubetypeboiler.
Itispopularportableboiler.
Itconsistofverysmallfloorarea.
Cochranboilerismodificationofsimpleverticalboilerwhere
heatingsurfacehasbeenincreasedbyincreasingnumbersof
firetubes.
Improvementoverthesimpleverticalboilerasitprovides
greaterheatingsurface.
Itisusedforsteamgenerationatlowrate.
Itisafiretubetypeboiler.
Itispopularportableboiler.
Itconsistofverysmallfloorarea.
Cochranboilerismodificationofsimpleverticalboilerwhere
heatingsurfacehasbeenincreasedbyincreasingnumbersof
firetubes.
Improvementoverthesimpleverticalboilerasitprovides
greaterheatingsurface.
Itisusedforsteamgenerationatlowrate.
Itisafiretubetypeboiler.
Itispopularportableboiler.
Itconsistofverysmallfloorarea.

4. Cont…
Cochran Boiler

5. Specifications of Cochran boiler
Shell diameter-2. 75m
Height-5.75m
Working pressure-6.5bar (max 15bar)
Steam capacity-3500kg/hr(max 4000 kg/hr)
Heating surface area-120 m²
Efficiency-70% to 75%
Shell diameter-2. 75m
Height-5.75m
Working pressure-6.5bar (max 15bar)
Steam capacity-3500kg/hr(max 4000 kg/hr)
Heating surface area-120 m²
Efficiency-70% to 75%

6. Characteristics of Cochran boilerCharacteristics of Cochran boiler
It is vertical.
It is portable.
It is a fire tube boiler.
The number of tubes are more (multi-tube).
It is internally fired.
It has natural circulation.
Solid as well as liquid fuel can be burnt.
It’s low pressure boiler
It is vertical.
It is portable.
It is a fire tube boiler.
The number of tubes are more (multi-tube).
It is internally fired.
It has natural circulation.
Solid as well as liquid fuel can be burnt.
It’s low pressure boiler

7. ConstructionConstruction

8. Construction
Theboilerconsists ofcylindrical shell, hemispherical fire box, fire
tubes and chimney.
The top of theshellhaving hemispherical shaped crown.
Thehemispherical crownofboilergives good strength to with
stand pressure of steam inside the boiler.
The hemispherical shape offurnacecan withstandhigh heatand is
also useful to increase radiant heat transfer from the furnace to
hemispherical furnace wall.
Thegrateis placed at the bottom of the furnace andash pitis
located below the grate.
Thefurnaceand thecombustion chamberare connected by
short flue pipe.
The wall of the combustion chamber is lined with thefire bricks.
Theash pitis located below the grate.
Theboilerconsists ofcylindrical shell, hemispherical fire box, fire
tubes and chimney.
The top of theshellhaving hemispherical shaped crown.
Thehemispherical crownofboilergives good strength to with
stand pressure of steam inside the boiler.
The hemispherical shape offurnacecan withstandhigh heatand is
also useful to increase radiant heat transfer from the furnace to
hemispherical furnace wall.
Thegrateis placed at the bottom of the furnace andash pitis
located below the grate.
Thefurnaceand thecombustion chamberare connected by
short flue pipe.
The wall of the combustion chamber is lined with thefire bricks.
Theash pitis located below the grate.

9. Working principles of Cochran boilerWorking principles of Cochran boiler
The water is supplied to theboilerthroughfeed check valve.
Thecoalis introduced to thegrate troughthefire door.
Thehot gasesproduced from furnace enterscombustion
chamberthrough flue pipe.
Thishot gasesenters intohorizontal fire tubes.
Convection heat transfer take place fromflue gasespassing inside
thetubesto water surrounded the tubes.
Theflue gasescoming from fire tubes enter intosmoke box.
Finally theydischargeto atmosphere through achimney.
Theashformed is collected inash pit.
Thesteamis collected throughanti-priming pipeon top of
the shell.
The water is supplied to theboilerthroughfeed check valve.
Thecoalis introduced to thegrate troughthefire door.
Thehot gasesproduced from furnace enterscombustion
chamberthrough flue pipe.
Thishot gasesenters intohorizontal fire tubes.
Convection heat transfer take place fromflue gasespassing inside
thetubesto water surrounded the tubes.
Theflue gasescoming from fire tubes enter intosmoke box.
Finally theydischargeto atmosphere through achimney.
Theashformed is collected inash pit.
Thesteamis collected throughanti-priming pipeon top of
the shell.

10. Mounting and AccessoriesUsed
Following mounting are required for thesafety and proper
operationof Cochran boiler.
Steam pressure gauge
Water level indicator
Dead weight safety valve
Feed check valve
Blow off cock
Steam stop valve
Man-hole
Fusible plug
Anti priming pipe and dampers are the boiler mounting.
Following mounting are required for thesafety and proper
operationof Cochran boiler.
Steam pressure gauge
Water level indicator
Dead weight safety valve
Feed check valve
Blow off cock
Steam stop valve
Man-hole
Fusible plug
Anti priming pipe and dampers are the boiler mounting.
Following mounting are required for thesafety and proper
operationof Cochran boiler.
Steam pressure gauge
Water level indicator
Dead weight safety valve
Feed check valve
Blow off cock
Steam stop valve
Man-hole
Fusible plug
Anti priming pipe and dampers are the boiler mounting.
Following mounting are required for thesafety and proper
operationof Cochran boiler.
Steam pressure gauge
Water level indicator
Dead weight safety valve
Feed check valve
Blow off cock
Steam stop valve
Man-hole
Fusible plug
Anti priming pipe and dampers are the boiler mounting.

11. Cont…Cont…
Fusible Plug:
If the water level in the boiler
falls below a predetermined
level, the boiler shell and
tubes will be overheated.
Fusible Plug:
If the water level in the boiler
falls below a predetermined
level, the boiler shell and
tubes will be overheated.

12. Cont…Cont…
Water Level Indicator:
This indicates the water
level in the boiler.

13. Cont…Cont…
Pressure Gauge:
This indicates the pressure
of the steam in the boiler.

14. Cont…Cont…
Steam Stop Valve:
It regulates the flow of steam
supply outside.
The steam from the boiler first
enters into an anti-priming pipe
where most of the water
particles associated with steam
are removed.
Steam Stop Valve:
It regulates the flow of steam
supply outside.
The steam from the boiler first
enters into an anti-priming pipe
where most of the water
particles associated with steam
are removed.
Steam Stop Valve:
It regulates the flow of steam
supply outside.
The steam from the boiler first
enters into an anti-priming pipe
where most of the water
particles associated with steam
are removed.
Steam Stop Valve:
It regulates the flow of steam
supply outside.
The steam from the boiler first
enters into an anti-priming pipe
where most of the water
particles associated with steam
are removed.

15. Cont…Cont…
SafetyValve:
The function of the safety
valve is to prevent the
increase of steam
pressure in the holler
above its design pressure.
SafetyValve:
The function of the safety
valve is to prevent the
increase of steam
pressure in the holler
above its design pressure.
SafetyValve:
The function of the safety
valve is to prevent the
increase of steam
pressure in the holler
above its design pressure.
SafetyValve:
The function of the safety
valve is to prevent the
increase of steam
pressure in the holler
above its design pressure.

16. Cont…Cont…
Feed CheckValve:
The high pressure feed
water is supplied to the
boiler through this valve.
Thisvalve opens towards
the boiler only and feeds
the water to the boiler.
Feed CheckValve:
The high pressure feed
water is supplied to the
boiler through this valve.
Thisvalve opens towards
the boiler only and feeds
the water to the boiler.

17. Cont…Cont…
Blow-off Cock:
Thewatersuppliedto
theboileralways
containsimpuritieslike
mud,sandand,salt.
Duetoheating,these
aredepositedatthe
bottomoftheboiler,
theyhavetoberemoved
usingblowoffcock.
Blow-off Cock:
Thewatersuppliedto
theboileralways
containsimpuritieslike
mud,sandand,salt.
Duetoheating,these
aredepositedatthe
bottomoftheboiler,
theyhavetoberemoved
usingblowoffcock.
Man-hole:providednear the top of the crown of shell for cleaning.

18. Maintenance
Start up
most furnace explosions occur during start up and when
switching fuels, so always follow the manufacturer’s guidelines.
Operation
Requires proper training, equipment familiarity and routine
maintenance procedures.
Shutdown
If the boiler is to be placed out of service for an extended period
of time, proper lay-up procedures are required and must be
followed.
Maintaining the normal operating water level (NOWL) in the boiler
A low water condition is the most common cause of boiler
failure.
Start up
most furnace explosions occur during start up and when
switching fuels, so always follow the manufacturer’s guidelines.
Operation
Requires proper training, equipment familiarity and routine
maintenance procedures.
Shutdown
If the boiler is to be placed out of service for an extended period
of time, proper lay-up procedures are required and must be
followed.
Maintaining the normal operating water level (NOWL) in the boiler
A low water condition is the most common cause of boiler
failure.
Start up
most furnace explosions occur during start up and when
switching fuels, so always follow the manufacturer’s guidelines.
Operation
Requires proper training, equipment familiarity and routine
maintenance procedures.
Shutdown
If the boiler is to be placed out of service for an extended period
of time, proper lay-up procedures are required and must be
followed.
Maintaining the normal operating water level (NOWL) in the boiler
A low water condition is the most common cause of boiler
failure.
Start up
most furnace explosions occur during start up and when
switching fuels, so always follow the manufacturer’s guidelines.
Operation
Requires proper training, equipment familiarity and routine
maintenance procedures.
Shutdown
If the boiler is to be placed out of service for an extended period
of time, proper lay-up procedures are required and must be
followed.
Maintaining the normal operating water level (NOWL) in the boiler
A low water condition is the most common cause of boiler
failure.

19. Advantage
It is compact and portable boiler therefore minimum floor
area is required.
Initial cost of boiler is less.
It can be moved and set up readily in different location.
Quick and easy installation.
Any type of fuel can be used ( coal or oil).
It is compact and portable boiler therefore minimum floor
area is required.
Initial cost of boiler is less.
It can be moved and set up readily in different location.
Quick and easy installation.
Any type of fuel can be used ( coal or oil).
It is compact and portable boiler therefore minimum floor
area is required.
Initial cost of boiler is less.
It can be moved and set up readily in different location.
Quick and easy installation.
Any type of fuel can be used ( coal or oil).
It is compact and portable boiler therefore minimum floor
area is required.
Initial cost of boiler is less.
It can be moved and set up readily in different location.
Quick and easy installation.
Any type of fuel can be used ( coal or oil).

20. Disadvantage
Steam raising capacity is less due to vertical design.
Water along with steam may enter the steam pipe
under heavy loads due to small steam space.
Efficiency is poor in smaller sizes.
Difficult in cleaning and inspection due to vertical
design.
The boiler require high head room.
Steam raising capacity is less due to vertical design.
Water along with steam may enter the steam pipe
under heavy loads due to small steam space.
Efficiency is poor in smaller sizes.
Difficult in cleaning and inspection due to vertical
design.
The boiler require high head room.
Steam raising capacity is less due to vertical design.
Water along with steam may enter the steam pipe
under heavy loads due to small steam space.
Efficiency is poor in smaller sizes.
Difficult in cleaning and inspection due to vertical
design.
The boiler require high head room.
Steam raising capacity is less due to vertical design.
Water along with steam may enter the steam pipe
under heavy loads due to small steam space.
Efficiency is poor in smaller sizes.
Difficult in cleaning and inspection due to vertical
design.
The boiler require high head room.

21. THANKS FORYOURATTENTION !!!THANKS FORYOURATTENTION !!!