The greater the angle, the greater the foreshortening. The degree of foreshortening of any line depends on its angle to the plane of projection.

There are an infinite variety of ways that the object may be oriented with respect to the plane of projection.

The angles between surfaces and edges appear either larger or smaller than the true angle. This produces a pictorial drawing that is easy to visualize, but because the principal edges and surfaces of the object are inclined to the plane of projection, the lengths of the lines are foreshortened. To create an axonometric view, the object is tipped to the planes of projection so that principal faces, such as the top, side, and front, show in a single view. When an angle is not parallel to the plane of projection, it appears either smaller or larger than the true angle. When a surface or edge of the object is not parallel to the plane of projection, it appears foreshortened. The feature that distinguishes axonometric projection from multiview projection is the inclined position of the object with respect to the planes of projection. Learn More Buy 3.8 Axonometric Projection Modern Graphics Communication, 5th Edition 3.25 Choice of Position in Oblique Drawings.

3.18 Orienting Ellipses in Isometric Drawings.

3.3 Sketching Circles, Arcs, and Ellipses.

The line diagram shows certain details such as operating and design temperature, operating and design pressure, insulation required, hydro test pressure, pipe support location, point of weld, and its type. The isometric drawing can be described as a pictorial representation that combines the height, width, depth, length, into a single view 30 degrees from its horizontal plane. The piping isometrics are used for the stress analysis and it is very useful for the draftsmen to create the shop fabrication spool drawings. The isometric drawings are really helpful for the complex or the larger piping system. Mostly the piping isometrics are created from orthographic drawings and this will be really useful for engineers. The finished isometric drawings are easier to understand in practical format than an orthographic line drawing. We can use either the single line or double line method. These drawings are used in pipelines that have bent more than in one place. This diagram shows both the horizontal and vertical planes. This drawing is widely used for industries because it can be drawn easily and it would display the object in a realistic way. So in this drawing three sides of an object can be viewed. The isometric drawing is a type of piping drawing and it shows the piping system in three dimensions (length, width, & depth).

Plumbing isometric drawings examples