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

The file best suited for bringing the material to accurate size with a high degree of finish is dead smooth file.

• These files have the finest tooth structure among all file grades.
• They remove the absolute minimum amount of material per stroke.
• Dead smooth files are used for achieving the highest possible level of

According to the Bureau of Indian Standards (BIS), these four grades are recommended for engineering files.

1. Bastard File: Used for heavy material removal.
2. Second Cut File: Ideal for achieving a good finish after initial shaping.
3. Smooth File: Designed to remove small quantities of material and provide a good finish.
4. Dead Smooth File: Used for achieving a high degree of finish and precise sizing.

• Different sizes of files within the same grade have varying sizes of teeth.
• This variation allows for adjustments in material removal and finishing capabilities based on the specific application and size of the file being used.
• Longer files tend to have coarser (bigger) teeth.

• The shape of a file is typically described by its cross-section.
• Files come in various shapes such as flat, round, half-round, triangular, square, knife edge, or specialized shapes.

• A flat file has a rectangular cross-section.
• This shape makes it versatile for general-purpose filing on flat surfaces, as well as for creating flat surfaces on workpieces.

• The edges of a flat file designed is Parallel for two-thirds of the length, then tapered.

• This is because flat files generally have parallel surfaces for most of their length, with a taper towards the end

• Flat files typically have double-cut teeth on their faces to enable rapid material removal and efficient filing.
• The double-cut pattern involves two sets of lines that cross each other, forming the teeth.
• This crisscross pattern allows the file to operate at opposite angles, facilitating aggressive material removal and better finishing in less time.

• The edges of a flat file typically have a single cut.
• This means that there is one row of teeth running in one direction along the edge, which is designed for finer filing and finishing work.
• The single-cut design allows for more control when working on edges, making it suitable for achieving a smooth finish.

• A hand file typically has a rectangular cross-section.

• This shape is designed to provide a good balance between strength and flexibility, making it suitable for various filing tasks, including smoothing and shaping surfaces.

• Hand files typically feature double-cut teeth on their faces, which allows for efficient material removal.
• This design enables the file to cut in both directions, making it effective for various filing tasks.
• One edge of the hand file is usually a single cut, which provides finer control and is useful for achieving a smooth finish.
• The other edge is often referred to as a safe edge, designed to protect finished surfaces and prevent accidental damage while filing.
• The presence of the safe edge makes these files particularly useful for filing surfaces that are at right angles to already finished surfaces, allowing for precision work without compromising the quality of adjacent areas.