Workshop Technology — Part 2 MCQs with Explanations

The diaphragm moulding machine is used to Give uniform sand hardness throughout the mould

Centrifugal casting is a process that delivers components of high material soundness. By spinning a mold while molten metal is poured into it, centrifugal force acts to distribute the molten metal in the mold at pressures approaching 100 times the force of gravity.

The temperature of the inner luminous cone of neutral flame is about 3200°C

The acetylene cylinder is usually painted with maroon colour. An acetylene cylinder has a different design from most other gas cylinders. It consists of a steel shell containing a porous mass. The acetylene gas in the cylinder is dissolved in acetone which is absorbed by the porous mass.

The oxygen cylinder is usually painted with Black colour

Punching is a sheet metal operation in which a cylindrical hole or any other desired shape is cut out from a metal sheet using a punch and die set . In this process, the punch applies pressure on the sheet metal, forcing the material into the die opening . The portion of the metal that is removed (the slug) is considered scrap, and the remaining sheet with the hole is the useful part. Piercing is a similar process, but it generally refers to making small holes or slots without removing significant material, often as part of a larger forming operation. Blanking is the reverse of punching. In blanking, the cut-out portion (blank) is the useful part, while the remaining sheet is scrap. Shearing refers to the cutting of a sheet along a straight line using shearing blades, not by punch and die action. Therefore, the operation of cutting a cylindrical hole in a sheet of metal using a punch and die is known as punching . Hence, the correct answer is Option C: Punching .

A moving mandrel is used in Tube drawing

The electrode tip diameter (d) in spot welding should be equal to $$\sqrt {\text{t}} $$ .

The parts of circular cross-section which are symmetrical about the axis of rotation are made by Hot spinning

The recrystallisation temperature of steel is 800°C

The teeth of hacksaw blade are bent Alternately towards right and left and every third or fourth left straight

The operation of bending a sheet of metal along a curved axis is known as Forming

In forehand welding, the angle between the welding torch and the work is more as compared to backhand welding. This difference in the angle of the torch makes the two techniques distinct. Forehand Welding: In this technique, the welding torch is held at an angle greater than 90 degrees in relation to the direction of the weld. This means the torch points slightly forward in the direction of welding. It is often used for applications where deeper penetration and faster travel speeds are required. Backhand Welding: In contrast, backhand welding involves holding the torch at an angle less than 90 degrees, with the torch pointing slightly backward in the direction of welding. It is commonly used when a more shallow weld with less penetration is desired. So, the angle is "more" acute in forehand welding compared to backhand welding. This distinction in torch angles allows welders to control the depth and profile of the weld bead to suit the specific requirements of the welding project.

Electron beam welding (EBW) is a fusion welding process in which a beam of high-velocity electrons is applied to two materials to be joined. EBW is often performed under vacuum conditions to prevent dissipation of the electron beam.

Structural shapes that can be made with this metal forming process include I-beams, H-beams, T-beams, U-beams, angle iron, channels, bar stock, and railroad rails. The most commonly rolled material is structural steel. It is made by Hot rolling.

A hacksaw is a fine-toothed saw, originally and mainly made for cutting metal. On hacksaws, as with most frame saws, the blade can be mounted with the teeth facing toward or away from the handle, resulting in cutting action on either the push or pull stroke.

V-Blocks are precision metalworking jigs typically used to hold round metal rods or pipes for performing drilling or milling operations. They consist of a rectangular steel or cast iron block with a 90 degree channel rotated 45 degrees from the sides, forming a V-shaped channel in the top.

Providing shear on the tool helps to reduce the cutting force in sheet metal operations. When shear is provided, the cutting action takes place progressively rather than simultaneously over the entire area, thereby decreasing the amount of material being cut at any instant. This progressive cutting lowers the cutting force, improves the quality of cut, and increases the tool life. Hence, providing shear on the tool effectively reduces the cutting force required during the operation.

The edge of a steel plate cut by oxygen cutting will get hardened when the carbon content is More than 0.3 percent

In average work, the tolerance produced by investment casting method is ±0.05 mm

In blanking the punched out piece is used and called a blank; in piercing the punched out piece is scrap. In blanking operation, the clearance is provided on punch.

Piercing is process in which punch operation cuts a hole/material by tearing operation from a final piece of sheet metal. Piercing is a blanking operation. In piercing operation, the clearance is provided on die.

A chisel is a tool that has a long metal blade with a sharp edge at the end. It is used for cutting and shaping wood and stone. The cross-section of a chisel is usually Octagonal

Cores are used to Form internal cavities in the casting and Improve mould surfaceand used to Form a part of a green sand mould core is a device used in casting and moulding processes to produce internal cavities and reentrant angles . The core is normally a disposable item that is destroyed to get it out of the piece

Upset butt welding is a welding technique that produces coalescence simultaneously over the entire area of abutting surfaces or progressively along a joint, by the heat obtained from resistance to electric current through the area where those surfaces are in contact

The consumable electrode is used in MIG arc welding

The stress in the flange region during the deep drawing process is a combination of radial tensile drawing stress and a tangential compressive stress. The blank-holder at the top of the workpiece exerts a compressive force at the upper surface of the blank during the drawing process.

Acetylene gas is stored in cylinders in Liquid form

Loam sand is a mixture of 50% sand and 50% clay

Green sand is a mixture of 70% sand and 30% clay

The blank diameter used in thread rolling will be A little larger than the minor diameter of the thread

The operation of cutting of a flat sheet to the desired shape is called Blanking

Cold working is the plastic deformation of metals below the recrystallization temperature. In most cases, such cold forming is done at room temperature. The major cold-working operations can be classified basically as squeezing, bending, shearing and drawing.

The neutral flame is the flame in which the amount of oxygen is precisely enough for burning, and neither oxidation nor reduction occurs. A flame with a good balance of oxygen is clear blue. The reducing and neutral flames are useful in soldering and annealing. The neutral flame has a one-to-one ratio of acetylene and oxygen. It obtains additional oxygen from the air and provides complete combustion. It is generally preferred for welding.

The width of slot cut by a hacksaw blade is Greater than the width of the blade.

The instrument which has all the features of try-square, bevel protractor, rule and scriber, is combination set. The combination square set is a measuring tool which is designed primarily for measuring angles and lengths. It is used by people working in a number of different trades, including woodworkers and engineers.

In a hot chamber die casting machine Nonferrous alloys with low melting temperature are casted. In hot chamber machinery contains the alloy melting pot as part of the machine itself and uses a gooseneck to inject material from the pot into the die. Materials used in hot chamber die casting are zinc, lead and magnesium alloys.

In a cold chamber die casting machine Melting pot is separate from the machine. Cold chamber die casting is ideal for metals such as aluminum which have a high melting point. During this process, metal is liquefied in a furnace at extremely high temperatures and then ladled into a cold chamber to be injected into the die.

A carburizing flame is advantageous for welding high carbon steel and hard facing such nonferrous alloys as Nickel and Monel. Carburizing flame is used to weld hard surfacing materials such as stellite.

A progressive limit gauge that serves to determine whether the measured part is within prescribed limits of tolerance. A progressive limit gauge has 'Go' and 'Not go' member on the same side of the gauge