Introduction / Context:
Sectional views are a core technique in engineering graphics used to reveal interior features that are hidden in standard orthographic views. A Cutting Plane line is drawn on a parent view to show where the object is imagined to be cut. The arrowheads on this line communicate a critical detail: the direction from which the cut face is viewed to create the section.
Given Data / Assumptions:
- A Cutting Plane line is labeled (for example, A–A) and has arrowheads.
- Hatching (section lining) appears on the cut surfaces in the derived sectional view.
- Standards such as ASME Y14 series and ISO graphics standards govern symbols and conventions.
Concept / Approach:
The Cutting Plane line specifies both the cutting location and viewing direction. The arrowheads point toward the direction of sight used to generate the sectional view. This assures that the sectioned geometry, hatching orientation, and visible edges are correctly interpreted relative to the chosen viewpoint.
Step-by-Step Solution:
Identify the Cutting Plane line on the parent view and read its label (e.g., Section A–A).Observe the arrowheads; they point in the viewing direction for the section.Locate the labeled sectional view; it must correspond to that direction of sight.Verify that features seen in the section match what would be visible when looking along the arrows.
Verification / Alternative check:
Mentally rotate the “glass box” or use a simple model: face the object in the arrow direction; the sectioned face should match the produced view.
Why Other Options Are Wrong:
Incorrect: Arrowheads do indicate viewing direction; denying this contradicts the convention.Applies only to revolved sections: Arrowheads are used for full, half, offset, and aligned sections as well, not just revolved sections.Used only in architectural drawings: Mechanical, civil, and architectural drawings all use this convention.
Common Pitfalls:
Confusing arrow direction with hatch direction; arrows set the view, hatch shows cut surfaces.Placing the section label incorrectly, leading to mismatched references.
Final Answer:
Correct
Discussion & Comments