Procedure for the setting of safety valves of Exhaust gas operated auxiliary boilers.
Safety valve fitted to boilers and
economizers may be adjusted by a fully qualified engineer, holding a First Class certificate of competency,
sailing in the rank of Chief engineer. In this case the engineer in question must inform an approved surveyor in
writing at the next port of call following the adjustment of valve.
The following procedure
should be followed for exhaust gas safety valve.
1.
Ensure
that when the valve was overhauled that it could lift by D/4 when the spring
tension was removed.
2.
Ensure
the drain lines are clear.
3.
Ensure
that recently calibrated gauge is connected to the economizer. More usually to
connect two gauges to ensure accurate setting.
4.
The set pressure of the safety valve would
be given to the Chief engineer by class.
This pressure should be similar to the previous set pressure of the valve.
5.
Ensure
that the main engine is operated above
50 % to ensure that the exhaust gas fired boiler is generating steam to
allow the test to continue.
6.
Gag
one of the 2 safety valves so that so that one only one valve is able to lift.
7.
Close the Exhaust Gas Boiler steam outlet
valve to raise the pressure in the boiler up to the set pressure.
8.
If
the valve does not lift at the correct pressure reduce the pressure and adjust
the spring tension.
9.
Carry
out the above mentioned procedure until valve lifts at correct pressure. Open
steam valve fully when safety valve lifts.
10.
Measure
the distance between the compression ring and valve body.
11.
Change the
gag over to set the other safety valve using the above mentioned procedure.
12.
After both
valves are set, release pressure and fit spacer rings beneath compression ring.
13.
Replace
easing gear and lock top cover to prevent spring adjustment.
14.
Record the
valves of the safety valve in the engine log book and prepare statement for the
Classification society.
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