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What does the unit "psi" represent?
Nidhin Chandran
- May 12th, 2011
Psi stands for pounds force per square inch and is a British unit commonly seen on pressure gauges
raja
- Sep 26th, 2007
PSI is a short form of Pounds Per Sqare Inch. it is the amount of pressure in pounds acting in a square inch of area.
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What are the different types of biaxial & triaxial stresses?
mohamed abdelkareem
- Feb 20th, 2012
In a biaxial stresses there are two stresses in two dimension say (x,y) and caused shape deformation , but in a triaxial stresses there are three stresses in three dimension say(x,y,z) and caused volumetric deformatio.
ahmedsaid2050
- Jan 26th, 2012
A biaxial state of stress is defined as a state of stress where one of the three principal stresses is equal to zero: 1 0 , 2 0 , 3 = 0 A triaxial state of stress is defined as a state ...
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Annealing, Normalizing, Carburizing
What is annealing, normalizing, carburizing w.r.t iron carbon equilibirium and also mention its temperature ranges.
Usman Adil
- Jan 30th, 2009
The explaination is same as mentioned above....But it should be noted that Annealing is used when we want ductility in material.Normalizing is used when we want hardness and carburizing is used when w...
mailmisterk
- Dec 11th, 2008
Annealing and normalizing are heat treatment techniques.in order to impart desired mechanical properties to the material heat treatment techniques are carried out. Annealing is the process of heating ...
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Fixed Gear
What is fixed gear?
BHAUTIK USDADIYA
- Sep 7th, 2012
Main gear is known as fixed gear.
ahmedsaid2050
- Jan 26th, 2012
A fixed-gear it is single speed like bicycle (or fixed-wheel bicycle, sometimes known as a fixie) is a bicycle that has no freewheel, meaning it cannot coast, as the pedals are always in motion when the bicycle is moving.
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Bending Moment
What is the shape of bending moment diagram if a lone moment act at the mid point of the simply supported beam?
d_tyro_22
- Jan 27th, 2010
Expression for bending moment in terms of distance 'x' measured from left end:= -(Mx/L) ; 0<=x<L/2=-(Mx/L) + M ; L/2...
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Increase Boiler Efficiency
How we can increase the efficiency of boiler without creating any effort?
dneipp
- Sep 20th, 2009
Different ways, 1. use a vent damper, 2. insulate steam pipes and condensate pipes. That will not increase the efficiency of the boiler, but will save substanial energy. Make sure the boiler is tuned in properly. Make sure your steam traps are working properly.
nilesh87
- Sep 10th, 2009
Increase boiler efficiency one percent for each 15 percent reduction in excess air or 40 degree Fahrenheit reduction in flue gas.
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Engine Coolant
Can we use the same coolant for cooling I.C. engine as well as for machining purposes? Why or why not?
vijay m
- Dec 30th, 2009
The most considerable property of coolant in viscosity which should be greater when used in Engine walls & should be lesser when used during machining operations.
shukla_vivek1011
- Sep 16th, 2009
The coolant required to use in I.C engines must posses somewhat greater viscosity as compared to the coolant used for any machine because, coolant of any machine got cooled after some periodic interval as compared to in case of any I.C engine coolant.
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Inspection Equipment
What is the minimum set of inspection equipment which we have to keep at site to inspect blasting and painting?
RAVI MENON
- Sep 16th, 2009
Blasting surface profile gauge,
Wet film thickness gauge,
Dry film thickness gaugerameshm04
- Aug 15th, 2009
For measure Blasting?readings good equipment Roughness meter and for painting ELCO Meter
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Calorific Value
What is Petrol Calorific Value?
arun govind neelan
- Dec 24th, 2009
It is defined as amount of heat energy produced when unit mass of fuel is burned1cal=4.184 joule
S.KALAIYARASAN
- Apr 21st, 2009
The calorific value of the petrol is 48,000kJ/kg.The highest calorific value fuel is hydrogen is 141,790 kJ/kg.
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Stress Concentration
What is Stress Concentration? Give numerical examples.
harsh.ankalkoti
- Aug 21st, 2009
It is the concentration of stress at a particular point or region such as holes, sharp edges, corners etc., This is due to the reduced cross section area.As we know stress= force / area........The ...
vrsaikumar
- Jun 25th, 2009
Stress concentration or the stress will be maximum at the joints such as T joints and L joints. This results in fracture of materials easily. This is the reason whenever a material is manufactured w...
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Pump Displacement
Explain What is positive and non-positive displacement?
vrsaikumar
- Jul 9th, 2009
Positive displacement pumps are those which prevents undesirable flow and pumps the fluid within the closed space. Ex: Reciprocating pumps, Rotary pumps. Its efficiency is more when compared to non-p...
sachinlshinde123
- Jul 3rd, 2009
Positive displacement pump are those which discharge specific amount & quantity is constant?non positive pumps are those which discharge random amount & quantity varies.
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Thermal Efficiency
Why the thermal efficiency of the engine decreases at part load?
kanthasami
- Jul 26th, 2009
There are always some mechanical losses in the engine while running. These losses are more or less same at all the speeds. When the speed decreases, the output will obviously decreases. But, the losses remain same. So, the overall efficiency also decrease.
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Disc Brake
Why do most of the vehicle have disc brake only in the front axle?
NSK7777
- Jul 26th, 2009
While applying brake, the momentum of the vehicle will be transferred to front portion so it is necessary to have more braking force on front axle, that is why disc brake is used in front axle.
Gambit
- Jul 19th, 2009
Most of the vehicles are front wheel drives which uses disc brake in the front axles. This is because the inertia of the vehicle towards the front is more. So, to control the speed it is necessary to ...
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Railway Engine Motor
What motor do they use in railway engines for traction?
hemalshah94
- Aug 27th, 2010
In Local memu train, series motor is used bec?it? requires high torque?initially?e.g. Anand Memu, Vadodara memuIn Express train, I.M motor or Shunt motor is used bec. it requires high torque as well as constant speed e.g Ashram Express
bhargavmech
- Jul 28th, 2009
Traction motors used to drive trains are series motors that provide the required torque and horsepower to get massive amounts of weight moving
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Bike Gear
While riding bike in 5th gear at speed around 70-80 km/hr. suppose by any means the speed decreases such as break, but keeping the gear on 5th. Engine of the bike stops. Why? Explain.
theleo
- Sep 4th, 2009
Generally in 1st and 2nd gear bike gives huge torque and less speed. But as we increase gears engine gives speed to maintain or increase speed which already bike have and give less torque. so, whe...
vivekzgoal
- Sep 2nd, 2009
Because the engine will not produce a required torque in 5th gear, so power is transmitted from wheel to engine through clutch and gear box and finally it stops the engine.
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Archimedes' Principle
According to Archimedes principle, mass of an object in water would be less than mass of an object in air.So imagine an object of 5 kg and weight of a vessel containing water as 100 kg. The total weight is 105 kg. Now place a weighing machine under the water vessel and immerse the object into the water. Now can I except the weighing machine shows the weight less than 105 kg?
sudeeb
- Dec 20th, 2010
Acc to A.P -- Weight of the water displaced is equal to the weight of the body. So the weighing scale indicate the same weight 105 kg. ?but when we lift the body we will feel low weight due to the upward?bouncy?force. and body float/sink depend upon the bouncy force and metacentre.?
prashanthsekar
- Feb 19th, 2010
Firstly the question Cannot be directly related to Archimedes Principle, As the principle states that when an Body is immersed in water, The amount of water displaced by the body is equal to the weigh...
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Rotating Objects
Why do objects rotating with more speed appearing to be stationary and sometimes appearing as rotating in the opposite direction?
bhargavmech
- Aug 11th, 2009
The wagon-wheel effect (alternatively, or stagecoach-wheel effect, stroboscopic effect) is an optical illusion in which a spoked wheel appears to rotate differently from its true rotation. The wheel c...
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Turbine Efficiency
Will Bleeding of steam increases or decreases the efficiency of Turbine? Explain.
daruljothi
- Mar 12th, 2010
Bleed steam will increses the cycle efficiency of the unit because:1. It was takenout after considerable work output by HP turbine and 2. It can be used fully for heating of feed water and etc., incre...
technowiz
- Nov 1st, 2009
Bleed steam will increase the turbine efficiency this process is basicaly known as regeneration.
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Vanadium in HSS
What is the use of Vanadium in High Speed Steels?
mailmisterk
- Dec 26th, 2009
Vanadium in hss forms very hard carbides and thus increases the hardness and increases the wear resistance
Manjiri ayade
- Oct 13th, 2009
Vanadium is corrosion resistant. HSS is basically used to manufacture cutting tool or machining tool which operate at faster rate. So this property of Vanadium is essential here.
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Car Parked in Sloped Area
Why vehicle does not move when its gear is applied though parked in slope area?
shefeerps
- Jan 22nd, 2010
In Geared Position the vehichle is connected to the piston. The gravity force on car parked in a slope is not enough to move the piston systems in the multi cylinder engines to expand or compress inside the cylinder.
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