QUADRANT SYSTEM OR ANGLE OF PROJECTION IN ENGINEERING DRAWING скачать в хорошем качестве

QUADRANT SYSTEM OR ANGLE OF PROJECTION IN ENGINEERING DRAWING

In engineering drawing, the quadrant system or angle of projection is a method used to represent three-dimensional objects on a two-dimensional plane. It involves specifying the angle at which the object is viewed and how it's projected onto the drawing sheet. The two primary angle systems used are: 1. First Quadrant System: In this system, the object is imagined to be placed in the first quadrant of a coordinate system. The angles of projection are measured clockwise from the reference line (usually the horizontal line) to the line of sight. The horizontal line is represented as 0°, and the vertical line is 90°. 2. Third Angle System: In the third angle system, the object is situated in the third quadrant of a coordinate system. Angles of projection are measured counterclockwise from the reference line (usually the horizontal line) to the line of sight. The horizontal line is still represented as 0°, but angles increase in the counterclockwise direction. The choice between these systems depends on the standards and conventions used in a particular engineering or drafting context. These systems help ensure that different engineers and drafters interpret drawings consistently, which is crucial for accurate design and manufacturing processes.