Types Of Lines In Civil Engineering Drawing

When looking at any drawing, you will soon notice that the way lines are drawn is a way of showing important details that are easily understood. For example, a centre line made up of a series of lighter long and short dashes, indicates the exact centre of the component that has been drawn.

Shown below are some examples of the different kinds of lines used in drawings.

Solid line

The solid line is of continuous, even strength. This line can be used as a light line in the process of developing or constructing the drawing that may be required to be erased at a later stage. It could also be a heavier line that is used to line in the completed drawing.

Hidden line

Hidden details are shown by a series of dashes making up a broken line. It is normal practice that you place a dash at the beginning of the hidden line and another at the end where it meets an intersecting line. In a scaled drawing, the hidden line can be measured from the start of the first dash, to the end of the last dash.

Centre line

Centre lines are drawn to indicate the exact centre of a component being drawn. They are made from a series of lighter long and short dashes.

Section line

Section lines are special lines placed on a drawing which indicate the area of the drawing through which an imaginary cut has been made to reveal internal details. These lines are drawn at full density and should be drawn at certain dimensions.

Dimension lines

Dimension lines are thinner than the lines used to outline a drawing. They are used to indicate the sizes of articles or objects instantly. Two types of dimension lines that can be used are shown below.

A dimension line.

Broken lines

Broken lines indicate that a break has been made in the drawing of an object which is too large to be drawn on the paper and had to be cut in order to fit on it. It is common practice when you are drawing a full size set-out to use broken lines rather than draw the full view.