Different types of lines

Basic tips for civil engineering  drawing

Now we are going discus one of the important part of  Civil Engineering  drawing . If you see any drawing you may find different types of line. These lines are differently named and classified.   Types of lines include the following:

visible – are continuous lines used to depict edges directly visible from a particular angle.

hidden – are short-dashed lines that may be used to represent edges that are not directly visible.

center – are alternately long- and short-dashed lines that may be used to represent the axes of circular features.

cutting plane – are thin, medium-dashed lines, or thick alternately long- and double short-dashed that may be used to define sections for section views.

section – are thin lines in a pattern (pattern determined by the material being "cut" or "sectioned") used to indicate surfaces in section views resulting from "cutting." Section lines are commonly referred to as "cross-hatching."

Civil Engineering Line Type

phantom - (not shown) are alternately long- and double short-dashed thin lines used to represent a feature or component that is not part of the specified part or assembly. E.g. billet ends that may be used for testing, or the machined product that is the focus of a tooling drawing.



Lines can also be classified by a letter classification in which each line is given a letter.

Type A lines show the outline of the feature of an object. They are the thickest lines on a drawing and done with a pencil softer than HB.

Type B lines are dimension lines and are used for dimensioning, projecting, extending, or leaders. A harder pencil should be used, such as a 2H.

Type C lines are used for breaks when the whole object is not shown. They are freehand drawn and only for short breaks. 2H pencil

Type D lines are similar to Type C, except they are zigzagged and only for longer breaks. 2H pencil

Type E lines indicate hidden outlines of internal features of an object. They are dotted lines. 2H pencil

Type F lines are Type F[typo] lines, except they are used for drawings in electro technology. 2H pencil

Type G lines are used for centre lines. They are dotted lines, but a long line of 10–20 mm, then a gap, then a small line of 2 mm. 2H pencil

Type H lines are the same as Type G, except that every second long line is thicker. They indicate the cutting plane of an object. 2H pencil

Type K lines indicate the alternate positions of an object and the line taken by that object. They are drawn with a long line of 10–20 mm, then a small gap, then a small line of 2 mm, then a gap, then another small line. 2H pencil