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HOW TO UNDERSTAND THE MANUFACTURING DRAWING

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Understanding of manufacturing drawing can seem quite difficult compare to normal drawing sheet. Because there is a huge number of manufacturing symbols  indicated on drawing sheet for manufacturing process of component. So designers must be  understand the manufacturing  symbols on drawing sheet based on types of  projection angles either they may be in  first angle projection or be in third angle projection. These projections indicate types of view of component on drawing sheet. As well as every designer must be know about how to understand  basic level of drawing standards  like scale, angles, gd&t symbols and paper size.

MANUFACTURING DRAWING INDEX:

  • Drawing template
  • Isometric drawing view
  • Orthographic drawing views (front view,rightside view,,topview,)
  • Section views (half section views,cross section views)
  • GD&T Symbols
  • Dimesions
  • Angle projection
  • Scale
  • BOM(Bill of Material)

Drawing template:

Drawing template  having two line structures called outer frame. This outer frame including  two lines alphabets and two numerical. two lines are like horizontal and vertical lines while lines are continue to other end but in the template lines are not shown. Because of types of view of parts located in between manufacturing drawing sheets so lines are not shown like dark. This case mostly used  when understanding the manufacturing drawing may be in that having any typically identified part of details then designers are using this alphabets and numerical to identify the part of details at the end of lines. Designers are mentioned there typical part of details.

TITLE BLOCK:

  • Name: Company name who prepared the drawing.
  • Name and date: Responsible designer who drew, checked, and approved the drawing.
  • Part name/description:  Describes what the part name.
  • Part/drawing number: Assigned number to identify the part in assembly part list.
  • Revision: Identifies the correct version of the drawing.
  • Scale (optional): Ratio of actual size of the part compared to the size of the part on the drawing.
  • It can be shown as 1:1 or 1=1. The first number represents the actual size of the part and the second number represents the print. In other words, 1:2 means the the print is double the actual size. Whereas 2:1 indicates the actual size is two times what is shown on the print.
  • Note: Use the dimensions to create drawing templete.
  • Size: Specifies the drawing sheet size;

A0 = 841 X 1189,

A1=594X841,

A2=420X594,

A3=297X420

A4=210X297 (in mm).

Isometric view of manufacturing drawing:

PISTON ISOMETRIC VIEWThe representation of the object in figure  is called an isometric drawing view. This is three-dimensional views called pictorial drawings.in the isometric view drawing show width,topview and height planes are placed on horizontal plane and isometric view shown 3d view of the object.

Orthographic drawing views (front view,rightside view,,topview,):

orthographic-views

  • Orthographic views are easy to understanding of actual visualization of the component.
  • Projection is a way of visualizing different views of an object from there different sides such as a top view, front view, Right side view, the object is rotated based on 90(degress) clockwise and so that the viewer viewing the object can see each side as the part is rotated.
  • These Views are appearing then drawn on a drawing sheet or on paper , enough views are drawn of the object to Help the person manufacturing of the part to get a good visualization of what the part looks Like after manufacturing.
  • The most common views drawn of an object in an orthographic drawings are the front view, top view, and right side view. After the views have been drawn on a sheet of paper notes and dimensions are then added for requirement of part.

 Section views (half section views,cross section views)

  • Section views are represents the intricate views of the componen
  • A half section view help of an object showing one-half of the view in section of component, The diagonal lines on the section drawing are used to indicate the area that has been theoretically cut.
  • These lines are called “hatching”. The lines are thin and are usually drawn at a 45-degree angle to the major outline of the object.
  • The indicating hatching on the drawing view it is a thickness of part.sectioning of the components to see the internal parts location,depth of holes,length of cut portions. 
  • Section views are mainly used for ASSEMBLING of parts, internal joints components and welding parts of details according to joining of particular part.section views are enough to drawn of component to help of joining of components by welding and fitting.section-view

Geometric Dimensioning and Tolerancing (GD&T) Symbols

  • Geometrical Dimensioning and Tolerancing is language of accurately communicate geometry requirement for associated features on assembly and individual manufacturing component drawings.
  • GD&T consist of dimensioning,tolerances,symbols,definations,rules and it is used for precisely communicate the functional requirements for the location, orientation, size, and form of each feature of the design models.
  • GD&T symbols provides accurate dimension from point to point of requirement of model.manufacturing of model based on the GD&T symbols.
  • Manufacturing of the drawing having concise of GD&T symbols to help of understanding the drawing.gdt-manufacturing-drawing

 

 

 SYMBOL CONTROL TYPE  NAME  DESCRIPTION
straightness  FORM  Straightness  Where an component of a surface is a straight line
flatness   FORM  Flatness  Surface having all elements in one plane
circularity   FORM  Circularity The form of surface of revolution(cone,cylinder,sphere)where all points of the surface intersected by any plane.
cylindricity   FORM  Cylindricity Like circularity, but applies simultaneously to the entire part of the surface
 profile of a line  PROFILE  Profile of a line Uniform amount of profile variation, either unilaterally or bilaterally, along a line element of a feature.
profile of a surface   PROFILE  Profile of a surface Uniform amount of profile variation, either unilaterally or bilaterally, along a line element of a surface.
perpendicularity  ORIENTATION  Perpendicularity Which is 90 deg perpendicular to the primary datum of its datum reference frame
angularity  ORIENTATION  Angularity  Which is having specific angle in relation to the primary datum of it’s datum reference frame
parallelism  ORIENTATION  Parallelism Which is having a equidistant at all points from datum plane
position  LOCATION  Position  Orientation of a features relation to it’s  datum reference frame
concentricity  LOCATION  Concentricity  In which two or more features having a same axis
symmetry  LOCATION  Symmetry  Symmetry of two planes about a center datum
circular runout  RUNOUT  Circular runout Circularity and coaxiality of each circular segment of a surface independently about a center datum
Total runout  RUNOUT Total runout Circularity,straightness,coaxiality and taper of a cylindrical surfaces about a center datum to rotated 360(deg)

DIMENSION: Dimension is a expressing length,area,height,mass,volume,weight,angle of one part details. It is representing on part by at different conditions. Expressing of details by according to designing and part shape.

Angle projection: Angle projection represents the drawing view position in drawing sheet and it helps to understanding the drawing. Which is use to programmers develop NC programming.drafters are developing manufacturing drawing based upon the projection angle . Projection angle plays main role in manufacturing drawing.

Scale:

It is showing real drawing with accurate dimensions. Scale is play main role in developing drawings to help of understanding of actual dimensions of it. Which is representing of drawing is reduced or increased.according to scale understand the drawings and drafters are mentioned in title box they show scales two types like 1:2,1:1,2:1 in 1:1 it is having actual view and real dimension of drawing. 1:2,1:3…etc drawing shows small but it has a actual dimension. 2:1,:2:2,2:3 drawings appearing big view but it is having actual dimensions.

scale 1:2

 1:1

scale 2:1

 

BOM(Bill of Material) : It represents the list of parts or components that are required for develop a product. It is a list of assembly,sub assembly,parts needed for manufacturing an end product. Also it is a list of materials for each component. It is a list of number of parts to be manufacture of product.

One Comment

  1. On the sample print given under the section for GD&T symbols, I’d like to know how the flange thickness near the left side of the drawing can be 35-36 mm, when the entire part is only 41.1-41.3 mm long! (I suspect it’s a typo…)

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