Posted tagged ‘piston ring’

Latest Placement Papers in Mechanical

September 16, 2011

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  • WHAT IS THE DIFFERENCE BETWEEN RATED SPEED AND ECONOMIC SPEED?

THE RATED SPEED TELLS US ABOUT THE MAXIMUM SPEED WHICH CAN BE ACHIEVED BY A VEHICLE OR SOME OTHER MACHINE BUT THE ECONOMICAL SPEED MEANS THE SPEED LIMIT AT WHICH THE MACHINE WORKS EFFICIENTLY WITH LEAST CONSUMPTION OF FUEL.EG-IN NORMAL BIKES(NOT RACING),THE MAX.SPEED LIMIT SHOWN ON SPEEDOMETER IS UPTO 120 KMPH BUT COMPANIES ALWAYS ADVICE THEIR CUSTOMERS TO DRIVE SUCH BIKES AT AROUND 60 KMPH TO HAVE MAXIMUM MILEAGE.

  • What is the purpose of scrapper ring

scrap the excess lube oil from the cylinder walls.there by preventing oil from entering combustion zone.

  • What are the causes of main engine black smoke?

There is many cause of black smoke.

1.is improper mixture of fuel supply by carburetor like very rich mixture so the fuel improper burn.

2. it is when piston or piston ring is fail so back side cooling oil release in combustion chamber it cause black smoke.

3.improper ignition system like not sufficient time of pressure rise delay period .

  • how cooling tower height selected?

The Function of a cooling tower is to cool the water coming from condenser.The water coming from condenser is hot and it is sprayed in a cooling tower and a air coming out from bottom cool the water which is coming down.Outside air is cool and air in inside the cooling tower is hot due to humidity.So there is a density difference between outside and inside air which caused pressure difference.

Pr Difference = g x H x ( density difference)

Where,

H = Height of chimney

Pr Difference = Pr Difference so that air can flow to cooling tower from outside

  • How does axial thrust balance in multistage pump?

A BALANCING LINE FROM DISCHARGE END IS CONNECTED TO SUCTIONSIDE TO BALANCE AXIAL THRUST.

  • how to calculate the boiler efficiency?any formula is there?

boiler efficiency= (heat transferred to feed water inconverting it to steam)/(heat released by completecombustion of fuel)

n(eta)= Mass of steam * (h- H(water))/(mass of fuel *calorific value fuel)

  • What is the significance of torque(in N-m) given in the engine specification

it give the moment about any point or simple rotation.

  • what is the exact requirement of priming?

priming is done in pumps to remove the entrapped air from the suction pipe thus aiding in smooth operation and avoiding in excess load on the pump.

  • What is the use of a PULLEY?

transmission of power(force) in rotary form

  • why does cycle rim don’t bend even in heavy loads?

Because of rubber tires. The load is distributed and its effect reduces i.e. tires absorbs heavy load and shocks with the support of steel rim.

The rim has many spokes. The spokes distribute the load equally and the rubber tires absorb more than half of the load.

  • How tonnage can be controlled in PLC base hydraulic press

customintegration of press interlocks to interfacingwith other parts of the hydraulic press line such as thefeeder or transfer systems.

  • what is BHP?

Brake horsepower is the amount of work generated by a motor under ideal conditions. This work is calculated without the consideration of effects of any auxiliary component, that may slow down the actual speed of the motor. Brake horsepower is measured within the engines output shaft and was originally designed to calculate and compare the output of steam engines.

As per the conventions, 1 BHP equals to:

  • 745.5 watts
  • 1.01389 ps
  • 33,000 ft lbf/min
  • 42.2 BTU/min

Latest Interview Questions & Answers

September 16, 2011

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1. What is Auto Dosing?

Auto dosing is an automated system of feeding the equipment with liquid products. It is the ideal way to ensure the correct calibrated dose at the right time every time in auto.


2. Difference between Codes, Standards and Specifications?

  • Code is procedure of acceptance and rejection criteria.
  • Standard is accepted values and compare other with it.
  • Specification is describing properties of any type of materials.

3.  Difference between Strainer and Filter


Strainer for coarse size, Filter is more accurate than Strainer.


4. What are differences between Welding & Brazing?

In Welding concentrated heat (high temperature) is applied at the joint of metal and fuse together.

In Brazing involves significantly lower temperatures and does not entail the melting of base metals. Instead, a filler metal is melted and forced to flow into the joint through capillary action.


5. What does a pump develops? Flow or Pressure

A pump does not create pressure, it only creates flow. Pressure is a measurement of the resistance to flow.


6. Which is heavier 1kg of Iron or 1kg of Cotton? and why?

Both of them have same weight. The only difference is the volume of Iron is small compared to Cotton.


7. What will be the position of Piston Ring?

In 180 degree angle the Top ring, Second ring and Oil ring are fixed. Position the ring approximately 1 inch gap below the neck.