Date post: | 23-Oct-2014 |
Category: |
Documents |
Upload: | shreyash-kumar |
View: | 210 times |
Download: | 8 times |
April 7, 2023 PMI Revision 00 1
Turbine pressure survey
April 7, 2023 PMI Revision 00 2
Pressure survey• Objective
– It gives a very useful indication of the internal condition of a turbine.
• Method– During acceptance test pressure at each tapping
point at full load is recoded and plotted on a graph.
– It can be compared at later date. If there is no deterioration, then the slope at full load will remain unchanged.
April 7, 2023 PMI Revision 00 3
150
100
75
0
Pressure B
ar
T.S
.V.
Impulse stage
1st Reaction
HP
exhaust
6 Heater.
IP Inlet
5 Heater
Dearator
LP
Inlet
Tapping points
Basic Turbine pressure survey diagram
Optimum 200 MW
April 7, 2023 PMI Revision 00 4
150
100
75
0
Pressure B
ar
T.S
.V.
Impulse stage
1st Reaction
HP
exhaust
6 Heater.
IP Inlet
5 Heater
Dearator
LP
Inlet
Tapping points
Turbine pressure survey diagram- effect of load change
Optimum 200 MW150 MW
April 7, 2023 PMI Revision 00 5
150
100
75
0
Pressure B
ar
T.S
.V.
Impulse stage
1st Reaction
HP
exhaust
6 Heater.
IP Inlet
5 Heater
Dearator
LP
Inlet
Tapping points
Turbine pressure survey diagram- effect of Internal wear
Optimum 200 MW
150 MW
April 7, 2023 PMI Revision 00 6
150
100
75
0
Pressure B
ar
T.S
.V.
Impulse stage
1st Reaction
HP
exhaust
6 Heater.
IP Inlet
5 Heater
Dearator
LP
Inlet
Tapping points
Turbine pressure survey diagram- effect of Internal restriction
Optimum 200 MW
April 7, 2023 PMI Revision 00 7
150
100
75
0
Pressure B
ar
T.S
.V.
Impulse stage
1st Reaction
HP
exhaust
6 Heater.
IP Inlet
5 Heater
Dearator
LP
Inlet
Tapping points
Turbine pressure survey diagram- effect of Heater outage
Optimum 200 MW
April 7, 2023 PMI Revision 00 8
Observation• If on a st. line but above the optimum line for a
particular load indicates– General wear throughout.– Worn diaphragm seals/ blade tip seals.
• If on a st. line but having kink in the pressure line, it indicates– Restriction to flow.
• If silica deposition is there then LP inlet pr.will show a high trend.
April 7, 2023 PMI Revision 00 9
THANK YOU