Short Answer
The number of views required in a drawing depends on the complexity and shape of the object. Generally, three principal views—front, top, and side—are used in orthographic projection to fully represent an object. However, for simple objects, fewer views may be enough, while complex shapes may require additional auxiliary or sectional views.
To determine the required number of views, engineers consider object symmetry, hidden details, inclined surfaces, and manufacturing needs. The goal is to provide enough information for accurate interpretation while avoiding unnecessary views that could clutter the drawing.
Detailed Explanation
Factors Affecting the Number of Views Required
- Complexity of the Object
- Simple objects can be described using one or two views.
- Complex designs require multiple views to avoid missing details.
- Object Symmetry
- If an object is symmetrical, one view with a centerline and dimensions may be sufficient.
- Asymmetrical objects require additional views for clarity.
- Hidden Features
- If important details are not visible in standard views, additional views are required.
- Hidden lines or sectional views can help show these details.
- Inclined and Oblique Surfaces
- Auxiliary views are needed if the object has angled surfaces that do not appear correctly in primary views.
- Manufacturing and Assembly Requirements
- Drawings should provide enough information for machinists, engineers, and quality inspectors to understand the design.
- Extra views help in avoiding errors in fabrication.
Standard Guidelines for Selecting Views
- Minimum Required Views
- One view: Used for flat or uniform thickness parts like plates.
- Two views: Suitable for cylindrical objects with no hidden features.
- Three views (Front, Top, Side): Standard for most mechanical components.
- Use of Additional Views
- Auxiliary Views: For inclined and oblique surfaces.
- Sectional Views: To show internal details clearly.
- Detail Views: Enlarged views for small or intricate features.
Conclusion
The number of views required in a drawing depends on the complexity, symmetry, and visibility of details. Engineers select the minimum number of views necessary to fully describe the object while avoiding unnecessary clutter. Proper view selection ensures clear communication in technical drawings, improving manufacturing accuracy and design interpretation.