Galvanising is a
Zinc diffusion process
Process of coating zinc by hot dipping
Process used for making thin phosphate coating on steel
None of the above
Correct Answer :
B. Process of coating zinc by hot dipping
Related Questions
According to Indian standards, the total numbers of tolerance grades are
8
12
18
20
In a _________, the molten metal is poured and allowed to solidify while the mould is revolving.
Die casting method
Slush casting method
Permanent mould casting method
Centrifugal casting method
For welding plates of thickness less than 5 mm, its edges
Do not require bevelling
Should be bevelled to a single-V or U-groove
Should have a double-V or U-groove on one side
Should have a double-V or U-groove on both sides
The casting method adopted for ornaments and toys of nonferrous alloys, is
Permanent mould casting
Slush casting
Die casting
Centrifugal casting
In a unilateral system of tolerance, the tolerance is allowed on
One side of the actual size
One side of the nominal size
Both sides of the actual size
Both sides of the nominal size
Cores are used to
Form internal cavities in the casting
Improve mould surface
Form a part of a green sand mould
All of these
The process extensively used for making bolts and nuts is
Hot piercing
Extrusion
Cold peening
Cold heading
In order to ram the sand harder at the back of the mould and softer on the pattern face, a ________ is used.
Sand slinger
Squeezing machine
Jolt machine
Stripper plate machine
Carburising flame is used to weld
Steel, cast iron, copper, aluminium etc
Brass and bronze
Hard surfacing materials such as stellite
All of these
In average work, the tolerance produced by investment casting method is
±0.05 mm
+0.2 mm
+05 mm
+1 mm
A zinc diffusion process is called
Galvanising
Anodising
Parkerising
Sherardizing
Lancing is the operation of
Cutting a sheet of metal in a straight line along the length
Removal of metal to the desired shape from the edge of a plate
Cutting a sheet of metal through part of its length and then bending the cut portion
Bending a sheet of metal along a curved axis
When the file is moved to and fro over the work, it is known as
Cross filing
Draw filing
Pull and push filing
None of these
When a pattern is made in three parts, the ________ is known as a drag.
Bottom part
Middle part
Top part
None of these
In a cold chamber die casting machine, only nonferrous alloys with _________ are casted.
Low melting temperature
High melting temperature
Both (A) and (B)
None of these
The operation of straightening a curved sheet metal, is known as
Drawing
Squeezing
Coining
Planishing
A casting defect which occurs near the ingates as rough lumps on the surface of a casting is known as
Shift
Sand wash
Swell
Scab
The process of increasing the cross-section of a bar at the expense of its length, is called
Drawing down
Upsetting
Spinning
Peening
Tandem drawing of wires and tubes is necessary because
It is not possible to reduce at one stage
Annealing is needed between stages
Accuracy in dimensions is not possible otherwise
Surface finish improves after every drawing stage
The acetylene cylinder is usually painted with
Black colour
White colour
Maroon colour
Yellow colour
Which of the following statement is wrong?
The angular clearance on dies varies from 0.5° to 1°
In drawing operation, the metal flows due to plasticity
In press operation, the size of the pierced hole is independent of the size of punch
None of the above
The algebraic difference between the maximum limit and the basic size is called
Actual deviation
Upper deviation
Lower deviation
Fundamental deviation
In a gas welding of mild steel using an oxyacetylene flame, the total amount of acetylene consumed is 10 litres. The oxygen consumption from the cylinder is
5 litres
10 litres
15 litres
20 litres
The operation of cutting a sheet of metal in a straight line along the length, is known as
Plunging
Notching
Slitting
Forming
The minimum size of a bloom is
5 cm × 5 cm
10 cm × 10 cm
15 cm × 15 cm
20 cm × 20 cm
In a hot chamber die casting machine
Ferrous alloys with low melting temperature are casted
Ferrous alloys with high melting temperature are casted
Nonferrous alloys with low melting temperature are casted
Nonferrous alloys with high melting temperature are casted
For arc welding
Alternating current with high frequency is used
Alternating current with low frequency is used
Direct current is used
Any one of these
A diamond pointed chisel is used for cutting
Flat surfaces
Grooves
Keyways
V-shaped grooves
In order to get uniform thickness of the plate by rolling process, one provides
Camber on the rolls
Offset on the rolls
Hardening of the rolls
Antifriction bearings
During hot working of metals
Poor surface finish is produced
Scale is formed on the metal surface
Close tolerances cannot be maintained
All of these