Components of ENGINEERING DRAWING
1. Title Block
2. Coordinate System
3. Types of Lines
- Part Outlines : This lines are drawing line used for physical boundaries of objects in which thinner lines are used for inner side of the object and thicker lines are used for outer side of objects.
- Hidden Lines : The lines which are not visible with naked eye on drawing but represent edges where surfaces meet behind the face.
- Center Lines : This line is used for holes and symmentrical features. It reduce the number of dimensions and make it easier for the reader.
- Dimension and Extensions Lines : Dimension line are used features measurement like size or length in drawing. Extension lines are extend towards element which are dimensioned.
- Cutting Plane Lines: This Lines are heavy line which shows the cutout path of a view.
- Break Lines : This line are used to seperate sections for calrification or to save drawing space.
4. Types of Views
- Isometric Views and orthographic : Isometric drawing represents the 3D drawing in which vertical lines are vertical and horizontal lines are drawn at angle of 30 degree. Orthographic drawing represents 3d drawing into 2 dimensions. It commonly represents 3 views Front View, Top View, Side View.
- Section Views : This views usually used for internal part clarification of objects by hidden lines.
- Detailed View : This View is used for giving close look for selected section which improves the readability of measurement in dimension.
- Auxillary view : This view represents the true dimensions part that are inclined surface which are not horizontal nor vertical.
Isometric and Orthogonal View
Detailed and Auxillary View
Scale Drawing is used to represent the actual size of the objects. Its the ratio of the objects linear dimensions represented to its actual dimensions.
6. Revision Block
This Block is tabulted for changes that are made on the drawing to roll the revision. These changes require modification to all drawing affected. It is usually at top right or with the title block of the drawing.
7. Bill Of Material
It is located upper part of title block which contains the list of all items and quantities require for the project. If there is too many items then seperate sheet is given.
Sometimes its not possible to produce exact product as per specification it may vary. According to the standard the tolerence means the amount of specific dimensions is permited to vary. The variation may be maximum and minimum limits is tolerance.
9. Size of Drawing
They are reference to the original drawing For example, if a drawing file is currently sized at 24″x36″, then a full size print of that file would be 24″x36″. A half size print, or 50% reduction, of the same 24″x36″ original would be 12″x18″