ENGINEERING CONCEPTS

Types of Dimensioning Methods and How to Understand Them

Dimensioning Methods

Understanding the dimensions in the engineering drawing it depends on the dimension lines which are showing the measure of the Line length, Circle Radius or Diameter etc.., 

  • An engineering drawing should contain the details of the regarding sizes. The expressions of details in terms in numerical values regarding distances between surfaces etc. 
  • On a engineering drawing use of lines and required symbols,units is known as Dimensioning.

METHODS OF DIMENSIONING

  1. Unidirectional System
  2. Aligned System

Unidirectional System : Unidirectional system method of dimensions are horizontally placed so that they can be read from Bottom of the drawing sheet. The methods of dimensions are easy to understanding the engineering drawing.

Aligned System : In this system of dimensions are placed parallel and above the dimension lines , preferably in the middle and not by interrupting the dimension lines.

TYPES OF DIMENSIONS 

Types of Dimensioning Methods and How to Understand Them

  1. Horizontal Dimension
  2. Vertical Dimension
  3. Parallel Dimension
  4. Perpendicular Dimension
  5. Chamfer Dimensions
  6. Angular Dimensions
  7. Cylindrical Dimensions
  8. Hole Dimensions
  9. Diameter Dimensions
  10. Radius Dimensions
  11. Thickness Dimensions
  12. Arc Length Dimension

Horizontal Dimensions 

  1. Horizontal Chain Dimension
  2. Horizontal Baseline Dimension

Vertical Dimension 

  1. Vertical Chain Dimension
  2. Vertical Baseline Dimension

Arrowheads

Dimension lines should be with required half size in dimension of arrow head size.

Example: Text size is 2mm then arrow head size is 1mm.