IOCL Junior Operator Fitter MCQ || IOCL Junior Operator General Science Questions and Answers

The screw in a hand vice is fastened to One leg.

• Screw Placement: The screw passes through one leg of the hand vice.
• Movable Jaw Attachment: The movable jaw is attached to the threaded end of the screw.
• Wing Nut: A wing nut is attached to the other end of the screw, allowing for easy turning to adjust the jaw position.

The primary use of a toolmaker’s vice is holding small work for filing, drilling, and marking.

• Precision: Toolmaker’s vices are known for their high precision and accuracy. They are designed to hold small workpieces securely and precisely while performing operations like:

  • Filing: Creating smooth, accurate surfaces.
  • Drilling: Precisely locating and drilling holes.
  • Marking: Accurately marking out lines and dimensions.

• This vise is made of mild steel and is accurately machined.
• Tool maker’s vises are precision ground devices good for holding delicate parts because the clamping pressure is easy to control.

The primary function of a leg vice is Holding work for bending and forging.

• Heavy-Duty Use: Leg vices are designed for heavy-duty work, such as bending, shaping, and forging metal. It is designed to withstand heavy use and distribute hammer blows without damaging the vise
• Sturdy Construction: They are typically made of strong materials like mild steel to withstand the forces involved in these processes.
• Secure Grip: While not ideal for precision work, they provide a strong hold on the workpiece during hammering and shaping operations.

The primary reason mild steel is preferred for leg vices is to avoid breakage during hammering.

• Leg vices are subjected to significant impact forces during hammering and forging operations.
• Mild steel, with its good ductility and toughness, can absorb these impacts without easily breaking or fracturing.
• Mild steel is relatively easy to shape and form, making it suitable for the manufacturing process of leg vices.

• Leg vices typically have a single point of contact or line contact with the workpiece along the bottom jaw.
• This line contact can result in uneven clamping pressure and a tendency for the workpiece to slip or rotate, especially during heavy hammering or forging.
• The limited contact area makes it more difficult to maintain precise control over the workpiece’s position during manipulation.

• Bench vices, especially toolmaker’s vices, are specifically designed for precision work.
• Accurate Jaw Alignment: The jaws are precisely aligned, ensuring that the workpiece is held securely and accurately.
• Smooth Action: The screw mechanism allows for fine adjustments of the jaw position, providing precise control over clamping pressure.
• Leg Vices: Primarily designed for heavy-duty work like forging and bending, they offer limited precision due to their design and the nature of the work performed on them.
• Hand Vices and Pipe Vices: While useful for specific applications, they are not typically designed for the level of precision required for tasks that involve precise measurements and alignments.

• The primary function of a try square is to check the squareness of a surface (90-degree angles).
• A try square is used to verify if a surface or edge is perpendicular (at a 90-degree angle) to another surface.
• It helps ensure accuracy in woodworking, metalworking, and other crafts where precise angles are crucial.
• Try squares can also be used to mark lines perpendicular to an edge.

• The accuracy of a try square is approximately 0.002 mm per 10 mm length.

• This level of precision makes it suitable for ensuring squareness in woodworking and metalworking applications.
• Try squares consist of two parts: a blade and a stock.
• The blade is the longer portion, usually made of metal, and the stock is the handle, typically made of wood, plastic, or metal.
• To use a try square, the stock is held against the edge of the material, and the blade is used to check the squareness.
• If there is a gap between the try square and the material, the material is not square

• A try square is primarily specified by the length of its blade i.e. 100 mm, 150 mm, 200 mm
• The length of the blade determines the size of the workpiece that can be accurately checked for squareness. Longer blades allow for checking larger surfaces.