Question { 5518 }

how much efficiency loss will took place in a steam turbine
due to low vacuum

Answer

In optimum vacuum the heat loss in exhaust of steam is
approx 450 kj/kcal. the temp. at the exhaust is 45. if the
vacuum drops in condenser the exhaust temp. will increase
as the exhaust temp. Increases the heat loss through the
condenser. it will reduce the overall efficiency of the
turbine. (pl. refer steam table for the temp. according to
the condenser pressure.)

Question { BARC, 24928 }

how can u increase the efficiency of power plant without
changeing in effort?

Answer

Dear friends,
Again I would like to say the same after reading of all
your answers.
Question is Increasing the efficiency without changing in
effort.
efficiency= heat utilised/heat supplied.
Designer calculated all posible optimum heat utilisation
and heat rejections. for that designed system we should
follow the designers datas. otherwise you can design so, u
are changing in efforts.
please follow the designers advice or discuss with them.

Question { 14118 }

What is the purpose of a turning gear?

Answer

The purpose of turning gear will to reduce the initial
torque required to rotate the rotor and it is used to
overcome from the rotor sag.

Question { 5150 }

What is the purpose of thrust bearing?

Answer

thrust bearing protect the machine by taking axial thrust
load. it is depending on the resultend thrust load.

Question { Balco, 20738 }

why vaccume required in turbine?

Answer

The last stage absolute temp. of steam will be near to
vacuum pressure. To maintain the dryness fraction of steam
in last stage vacuum required in the down stream of steam
flow. so, vacuum need in condenser.(P1V1/T1=P2V2/T2.)in
condenser there is no temp. drop. so P1V1=P2V2. the volume
of condenser is more than last stage area. so, pr. will be
less than last stage pr.

Question { 4821 }

What is hammering in steam or water flow pipe line. how it
is happening.

Answer

in the water flow air will cause for hammering because of
dencity difference of liquid and air. both will have
different velocity the water hit the pipe wall and
hammering is happening. in the steam line also the same
phenomina happening. and one more is if the pipe line is
cool then the steam contrased when come contact with cool
pipe. it also cause for hammering.
there should not be any different dencity fluid while flow.

Question { RRB, 3621 }

What are the methods of heat transfer?

Answer

Conduction
Convection and
Radiation

Question { RRB, 3656 }

What is thrust bearing?

Answer

It takes Axial load to keep the rotor in centre position.
it is the sacrificing mechanisum to protect the rotor
internals.(Axial clearences in the bearing is less than
Internal clearence of fix to moving parts.)