power generation process plant industrial...
TRANSCRIPT
Integral Valve InterlocksApplication Data Sheet
Boiler Blow-Down Valves
Industrial boilers often have several manual blow-down valves to perform the process of removing sludge from the boiler. This regularly performed process of manual blow-down of the bottom of a boiler can become a very dangerous situation if not completed correctly. For the operations to be carried out safely and without incident, only one valve should be opened at any time to prevent the blow-down fluid from being directed back into the boiler.
Using Kirk Key Eagle Valve Interlocks, as shown in the application scheme overleaf, will ensure that the proper sequential procedure is followed to perform the blow-down process.
www.kirkkey.comProcess safety Control
Indu
stri
esPower Generation
Process Plant
Industrial Boilers
Multi-Turn Valve Interlock
Quarter-Turn Valve Interlock
INITIAL SYSTEM STATUS: All valves are locked closed with Key A held in the Control Room.
SYSTEM OPERATION: 1) Key A is issued from Control with instruction to operate
blow-down valve 1, 2 or 3.
2) Enter Key A into blow-down valve 1, 2 or 3 and operated the valve to the open position. Key A is trapped in the valve lock when the valve is open so it cannot be used to operate any other valve.
3) Once the blow-down operation has veen completed, close the valve and lock closed by removing Key A.
4) Repeat operation for other blow-down valves.
5) On completion of operation all blow-down valves return Key A to Control to confirm the process is completed.
Interlocking Logic
Operation
Integral Valve interlocksApplication Data Sheet
Interlocking Sequences can be designed to suit any operational or Process Requirements
Global Headquarters | 9048 Meridian Circle NW | North Canton, OH 44720 | USA 800.438.2442 | FAX 330.497.4400 | [email protected]
Boiler Blow-Down Valves
The interlocking logic shown illustrates a typical boiler 3 valve blow-down valve system.
Note: All valve locks to be single key locks; Key Free valve locked closed.
LegendSingle Key Valve Locked Open
Single Key Valve Locked Closed
Key Free Key Trapped
STEP
1
2
3
4
A
B
C
B
A B C
B
C
B
A
KEYIN
KEYOUT
SequenceControl Unit
H2 Valve CO2 Valve Air Valve
Operating Knob
STEP
1
2
3
4
A
B
C
B
A B C
B
C
B
A
KEYIN
KEYOUT
SequenceControl Unit
H2 Valve CO2 Valve Air Valve
Operating Knob
A
Key “A” HeldIn Control
A A A
Boiler
Blow-DownValve 1
Blow-DownValve 2
Blow-DownValve 3
Drain