Oxyacetylene reducing flame is used while carrying out welding on__________________?
(A) Alloy steel
(B) Grey cast iron
(C) Mild steel
(D) High carbon steel
Adhesives__________________?
(A) Can’t be used in the form of pressure sensitive tapes
(B) Can’t join two dissimilar metals
(C) Cure instantaneously after application on a surface
(D) None of these
Name the safety device used to protect the boiler, when the water level falls below a minimum level ?
(A) Blow down valve
(B) Blow off cock
(C) Fusible plug
(D) Safety valve
_______________ rubber is generally used for making ‘O’ rings used for vacuum sealings?
(A) Natural
(B) Neoprene
(C) Butadiene
(D) Nitrile
A fluid is termed as the Newtonian fluid, when the shear stress is _________________ the velocity gradient ?
(A) Independent of
(B) Inversely proportional to
(C) Directly proportional to
(D) None of these
Pick out the wrong statement ?
(A) Cold cracking of a weld is due to the presence of hydrogen gas in the weld
(B) True stress is given by, ζ = ζE (1 + εE), where ζE and εE are engineering stress and engineering strain respectively
(C) Phosphorous can be easily recovered in the iron blast furnace
(D) High residual stress at the surface is beneficial for fatigue properties of a material
Pick out the wrong statement ?
(A) For a pressure vessel to be classified as ‘thin vessel’, the ratio of wall thickness to mean radius is less than 0.1
(B) For calculating forces and efficiency of riveted joint, either rivet diameter or rivet hole diameter is used in case of pressure vessel and in structural work
(C) Longitudinal joint is normally made butt joint to maintain the circularity of the vessel
(D) Maximum diameter of the opening provided in a pressure vessel, which does not require any compensation is 200 mm
Identify the correct statement?
(A) Sphlerite is zinc oxide
(B) The first law of the thermodynamics is stated as δE = δQ – δW
(C) Lead can be produced in a blast furnace
(D) T. ferrooxidans is a fungus that can be used for leaching chalcopyrite
Pick out the wrong statement ?
(A) Weldability of high carbon steel is poorer compared to low carbon steel
(B) Invar is a magnetic alloy
(C) Magnetic permeability of the diamagnetic material is less than one
(D) Martenistic transformation never goes to completion (i.
(D) , 100%) at room temperature
Pick out the wrong statement ?
(A) A ferromagnetic material becomes paramagnetic above the ‘Curie temperature’
(B) Permanent magnets are made of hard materials, whereas electromagnets require soft magnetic materials
(C) Soft magnetic materials (e.g., pure iron) have higher permeability and low hysterisis loss and coercive forces
(D) Tungsten steel and alnico are not hard magnetic materials