Types of Lines Based on its Application

LINES

TYPES OF LINES BASED ON ITS APPLICATION

Lines are classified as below based on its application. 

1. Visible outline (or) object line : To show the outer visible feature of the object. 

2. Section line (or) Hatching line : It is used to section an object.

3. Centre line : To show the centre and location of cylindrical, conical and spherical object. 

4. Hidden line : To show the invisible (or) hidden parts of the drawing. 

5. Construction line : These lines are used to construct an object. Generally these lines do not appear in finished drawing, erased after finishing the drawing. 

6. Dimension line : These lines are used to give dimensions of an object. 

7. Extension line : These lines are used to draw the dimension line. Generally in between two extension lines a dimension line is drawn. 

8. Projectors line : These lines are used to project a part of the drawing. 

9. Cutting plane line : These lines are used to show the edge of the cutting plane. 

10. Short break line : These lines are used to show the break of an object for a short length. 

11. Long break line : These lines are used to show the break for a considerable length of the object. 

Some of the lines of the above are shown in Fig. 3.1.