Answer / kaizad

As soon as steam stop valves are closed there is no control on coast down speed of turbine unless vacuum break valve of condenser is opened. Normally it takes approximately 55mins to coast down from 3000rpm to 20-30rpm barring gear speed. We keep watch on all turbo visors parameters in such times

Answer / m saqib

there is no control on coast down speed of turbine except vacume breaker.when turbine trip the steam stop valve should be closed.when turbine speed reaches 2800 rpm then we open the vacume breaker .then turbine speed reduce > than under vacume.

Answer / sbr

First off all we have to  close prds line valve due to prds pre low and vaccume also low that meens condenser pre high in the case turbine was tripped with low vacume after that close the esv. Why turbine shaft free fall in down when ever having vaccume in condenser  rpm slowly dicresed even that time shft having some load then we crose the critical speed some vibrations are coming so first shaft free only can crose the critical speed

Answer / chinmay kumar patra(npti)

open the vacuum breaker so speed retardation will be high and it will cross the critical speed rapidly.so no danger

Answer / sappy

Max speed at which turbine can rotate with load of maximum load

Answer / chanchal rajput

As we closed esv after that speed of the turbine goes to
slow down automatically we can not any thing as it cross the
critical speed , for short time vibration increase but after
that goes slow down and turbine stop .Some turbine run above
the critical speed and some below the critical speed .

Answer / ankit

barring gear motor is used to cross the critical speed which is 20-25% of rated speed

How to decide Heating surface area of boiler on their steam generating capacity?

4 Answers  

Difference between directional earth fault and non-directional earth fault

2 Answers  

if suppose boiler has high heavy tube leakage, so in which time we feed the water in a boiler. can we stop the feed water at particular combustion temperature.

4 Answers  

I am opertaing generators which are beyond 14000hrs and now the fuel consumption is about 2kw per liter of diesel. The engines are due for overhauling. is this normal

1 Answers  

Need of oxygen dosing in super critical powerplants?

5 Answers  

what is restricted earth fault explain in details

0 Answers   Greenko, JSW,

What is difference between secondary Air & Tertiary Air and Their use.?

0 Answers   Bhel,

what is significance of canister vent in condensate extraction pump & difference between vacuume balancinf line & canister vent

3 Answers   NTPC, Tata Power,

whatis means of PPA & FSA OR SFA in power plant operation

2 Answers  

What is wheel chamber in steam turbine?is it impulse blades are called wheel chamber in the steam turbine?

1 Answers  

what is voltage transformer explain in details

5 Answers   Khulna Power, NCC, Reliance Power,

why seal air fan is used and where it is used and where is suction taken from

7 Answers   Bhel, ETO,