ALLInterview.com :: Home Page            
 Advertise your Business Here     
Browse  |   Placement Papers  |   Company  |   Code Snippets  |   Certifications  |   Visa Questions
Post Question  |   Post Answer  |   My Panel  |   Search  |   Articles  |   Topics  |   ERRORS new
   Refer this Site  Refer This Site to Your Friends  Site Map  Bookmark this Site  Set it as your HomePage  Contact Us     Login  |  Sign Up                      
Google
   
 
Categories >> Engineering >> Mechanical Engineering
 
 


 

 
 Civil Engineering interview questions  Civil Engineering Interview Questions (3124)
 Mechanical Engineering interview questions  Mechanical Engineering Interview Questions (3300)
 Electrical Engineering interview questions  Electrical Engineering Interview Questions (13436)
 Electronics Communications interview questions  Electronics Communications Interview Questions (2385)
 Chemical Engineering interview questions  Chemical Engineering Interview Questions (420)
 Aeronautical Engineering interview questions  Aeronautical Engineering Interview Questions (77)
 Bio Engineering interview questions  Bio Engineering Interview Questions (17)
 Metallurgy interview questions  Metallurgy Interview Questions (80)
 Industrial Engineering interview questions  Industrial Engineering Interview Questions (165)
 Instrumentation interview questions  Instrumentation Interview Questions (2398)
 Automobile Engineering interview questions  Automobile Engineering Interview Questions (107)
 Mechatronics Engineering interview questions  Mechatronics Engineering Interview Questions (38)
 Marine Engineering interview questions  Marine Engineering Interview Questions (45)
 Power Plant Engineering interview questions  Power Plant Engineering Interview Questions (80)
 Engineering AllOther interview questions  Engineering AllOther Interview Questions (1203)
Question
what is critical speed of a turbine
 Question Submitted By :: Mechanical-Engineering
I also faced this Question!!     Answer Posted By  
 
Answer
# 1
Turbine shaft material has its own natural frequency, when
turbine rotates on such a speed that frequency of shaft
become close to its natural frequency, machine causes noise
& high vibrations because of resonance due to matching of
frequency. Running of Steam "TURBINE" on this speed is
avoided & this is called Critical speed. A turbine may have
more then one critical speed, which may depend upon number
of couplings.

it is denoted by w(omega).
 
Is This Answer Correct ?    45 Yes 5 No
Guest
 
Answer
# 2
Turbine shaft material has its own natural frequency, when
turbine rotates on such a speed that frequency of shaft
become close to its natural frequency, machine causes noise
& high vibrations because of resonance due to matching of
frequency. Running of Steam "TURBINE" on this speed is
avoided & this is called Critical speed. A turbine may have
more then one critical speed, which may depend upon number
of couplings.

it is denoted by w(omega).
 
Is This Answer Correct ?    20 Yes 3 No
Guest
 
 
 
Answer
# 3
Turbine shaft material has its own natural frequency, when
turbine rotates on such a speed that frequency of shaft
become close to its natural frequency, machine causes noise
& high vibrations because of resonance due to matching of
frequency. Running of Steam "TURBINE" on this speed is
avoided & this is called Critical speed. A turbine may have
more then one critical speed, which may depend upon number
of couplings.............
 
Is This Answer Correct ?    9 Yes 3 No
Kuldeep Thakur
 
Answer
# 4
The angular speed of rotating machinery at which excessive vibration is produced; at this speed the periodic disturbing force coincides with a mechanical resonance of the shaft and/or of the machinery or its supports.this effect in turbine is called critical speed of turbine 
Is This Answer Correct ?    5 Yes 1 No
Sornakumar
 
Answer
# 5
it is the phase of speed at which the natural frequency of the turbine shaft matches with the frequency at the speed. during this period more vibration and noise will come. to avoid this,(in fact we can not avoid) acceleration will be increased so that less time to cross the critical speed. thanking you. 
Is This Answer Correct ?    2 Yes 0 No
A.saravanan
 
Answer
# 6
when the normal rpm of turbine coinside with the natural frequency of tranverse vibration of the shaft.at this the vibration tends to infinity and causes of deflection of shaft. 
Is This Answer Correct ?    1 Yes 0 No
Sunil
 
Answer
# 7
actually the critical speed of turbine should not based
entirely on resonance effect....the critical speed is based
on the uniform speed of the generator .....and we ensured
this should not equal to natural frequeny
 
Is This Answer Correct ?    9 Yes 9 No
Raja
 
Answer
# 8
The Critical Speed is The Speed at Which the Center of mass
Not Equal to The Center of Rotation
 
Is This Answer Correct ?    7 Yes 10 No
Salah
 
Answer
# 9
In witch speed turbine vibration is most
Violently,it is due to many causes such as
Imbalance or harmonic vibration set up by entire mechine
 
Is This Answer Correct ?    0 Yes 4 No
Naresh Puli
 

 
 
 
Other Mechanical Engineering Interview Questions
 
  Question Asked @ Answers
 
what is unit of mechanical work nand piower ? Hindustan-Unilever-Limited 5
Where is Salar Jung Museum located? HAL 3
plz tell me the types of air compressors? & purpose of air drier?   3
the avg piston speed of an internal combution engine increases as cylinder dimension decreases justify? L&T 5
What is pitch RRB 2
what is the highest critical temprature of refrigerant? Hitachi 2
What does SAE-40 represents? and what is a multi-grade oil?   1
Why are not use ball bearing insted of roller bearing?   4
define stress   6
what are da different process to make gear TATA 5
I'm a Entrepreneur, now I'm seeking a job in the same domain in an Engineering company.I'm planning to leave my business to my Brother.How can I positively explain my sitivation in an interview to impress my employer. Pls advise   1
i woule my experiences in BARC i recently gone for the interview.. they dont consider u r dress code and all, even u can go in a jeans and tea shirt.they dont careabout u r personality , profile .. Theytest (complety) our technical knowledge.. so u have to prepare well in not only the basics but also in depth.. Even the did not consider the percentile in GATE.. One guy got 99.63 in gate but did not given medical. so u have to be very stiff and togh technically.. u should have a lot of luck too,because right panel selects u.. u dont expect what,how in Barc,only why.i amnot frightening u, i am telling u some facts i have faced.. istead of all i did it superbly and waiting for the result.. if u want more information, u can email me ,call me at any time.. BARC 31
 
For more Mechanical Engineering Interview Questions Click Here 
 
 
 
 
 


   
Copyright Policy  |  Terms of Service  |  Articles  |  Site Map  |  RSS Site Map  |  Contact Us
   
Copyright 2013  ALLInterview.com.  All Rights Reserved.

ALLInterview.com   ::  KalAajKal.com