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

• Narrow steel rule is designed with a reduced width to access and measure dimensions in confined spaces such as narrow slots, keyways, and small-diameter blind holes, where standard steel rules cannot fit.
• The rule has a width of approximately 5 mm and a thickness 2 mm

• The primary purpose of a scriber in layout work is to scribe lines that indicate the dimensions of a workpiece for machining or filing.
• A scriber is a hand tool used to mark lines on metal workpieces before machining.
• This process, called scribing, is a part of marking out and is used instead of pencils or ink lines because scribe lines are thin and semi-permanent.

• Scribers are commonly made of high carbon steel.
• Some scribers have a tip made of cast steel that has been hardened and tempered

• Dividers are primarily used for scribing circles, arcs, and transferring distances.
• They have two sharp points, one for the center and the other for scribing or marking

• The primary purpose of a datum is to provide a reference point for measurements.
• It serves as a common position from which measurements can be accurately taken, ensuring consistency and precision in layout and machining processes.

• Calipers are considered indirect measuring instruments because they are used for transferring measurements from a steel rule to a job and vice versa.
• They don’t provide a direct reading of the measurement itself, but rather act as a transfer tool.
• The measurement is then read from the steel rule.
• Calipers are classified based on their joints (firm joint or spring joint) and legs (inside or outside).

Calipers are classified based on their joints and legs.

• Joints: Calipers are available in two general designs, spring-type and firm-joint.
• Legs: Calipers have different leg types for specific measurements.
  • The three common types of calipers are the inside, outside, and hermaphrodite calipers.
  • Calipers can have legs designed for measuring inside dimensions, outside dimensions, or for layout work like scribing lines

• The primary purpose of using punches in layout work is to make layout dimensions permanent.
• Punches are used to create indentations or impressions on a workpiece, marking locations, transferring dimensions, or aligning holes.
• These marks serve as permanent reference points for machining or other operations

• The point angle on a center punch is 90°.
• The mark made by this punch is wide but not very deep.
• It is used to locate holes for drilling.

• The primary use of a center punch is locating the center of holes.
• The main job of a center punch is to mark exactly where you need to drill a hole.
• It makes a little dent so your drill bit doesn’t slip around when you start drilling.