Short Answer:
A removed section is a special type of sectional view used in engineering drawings to show the internal details of a specific part of an object, but it is drawn away from the main view. It is “removed” from its original position to keep the drawing clean and uncluttered.
Removed sections are used when a part has complex internal features like grooves, holes, or slots that are difficult to understand in regular views. These sections help engineers, machinists, and fabricators to clearly visualize and measure those internal parts without confusion.
Detailed Explanation:
What Is a Removed Section and Where It Is Used
In mechanical engineering drawings, sectional views are used to make the internal features of a component visible. Normally, a section view is drawn in line with the cutting plane, either next to or directly on the main view. But sometimes, adding a section view in the same area can make the drawing too crowded or messy. In such cases, a removed section is the best option.
A removed section is created by cutting through a specific portion of the object and then placing that sectional view somewhere else on the drawing sheet. This helps in clarity, simplicity, and space management without losing any detail.
Features of a Removed Section
- Not in direct alignment with the cutting plane
- Clearly labeled (e.g., Section A-A, B-B)
- Shows only the portion that was cut
- May be scaled differently for clarity
- Positioned anywhere on the drawing sheet
Steps to Create a Removed Section
- Select the Area to Be Cut
- Identify the portion of the object with internal details to reveal.
- Use a cutting plane line to mark the location in the main view.
- Draw the Sectional View Separately
- Imagine cutting the part along the marked line.
- Show the internal features as if looking straight at the cut face.
- Place this view at a different location on the same sheet.
- Label the Section Properly
- Mark the section as “Section A-A”, or similar, for easy reference.
- Use arrows on the cutting plane to show viewing direction.
- Add Dimensions and Notes
- Include only the details relevant to the cut portion.
- Avoid repeating information shown in other views.
Where Removed Sections Are Used
Removed sections are very helpful in many mechanical engineering situations:
- Small and Complex Parts
- Used to show fine internal features like:
- Grooves
- Holes
- Steps or shoulders
- Slots and keyways
- Especially useful when these features cannot be shown clearly in the main view.
- Avoiding Overcrowded Drawings
- If the main view is already full of details, hidden lines, and dimensions, adding a section next to it may create confusion.
- By moving the section to another place, the drawing becomes neater and easier to read.
- Repetitive Features
- When similar parts are repeated in a component (like gears or fins), one removed section can be used to describe all of them.
- Showing Assembly Details
- In assembly drawings, removed sections help show:
- How parts fit together
- Clearances and interlocks
- Hidden features of mating parts
- Better Visualization
- Sometimes, drawing a section to a larger scale and placing it away from the view helps the user see details more clearly.
- This helps in quality control and manufacturing accuracy.
Example
Imagine a shaft with a groove near its center. In the front view, the groove is not clearly visible. Drawing a removed section at the groove location allows you to show its shape, depth, and width in detail without cluttering the main view.
Conclusion
A removed section is a powerful tool in engineering drawing used to present the hidden or internal features of a specific part clearly and separately. It improves the readability of complex drawings by removing visual clutter. This section is especially useful in designs that require precision, tight fits, or clear assembly instructions. When used properly, removed sections ensure that engineers, machinists, and inspectors can understand and produce parts exactly as intended.