Post Summarization:
● Introduction.
● Size of drawing sheets.
● Margin.
● Borderlines.
● Title block.
● Rules for selecting Titles.
● Revision Table.
● Notes.
● Tutorial Videos (Coming Soon!)
INTRODUCTION:
A drawing sheet consists of an engineering drawing and must have some other aspects too i.e. Border lines, Title block, Notes, etc for better demonstration of the drawing.
The layout of border lines and title blocks should always be done in some specific manner on the drawing sheet as it's not only a necessity for increasing the visual orientation of the drawing sheets, moreover, these help to read the drawing sheet more speedily in a systematic way.
SIZE OF THE DRAWING SHEET:
The size of the drawing sheet in detail can be found in the TECHNICAL DRAWING AND INSTRUMENTS of this blog.
MARGIN:
Margin or Marginal lines are drawn on the drawing sheet only where the untrimmed size of the drawing sheet is provided.
Generally, in the paper industry, trimmers are used to trim drawing sheets along these lines. After trimming, the paper sheets would be of the recommended trimmed sizes as per specifications and would easily be available in the market for use.
BORDERLINES:
The border lines are which enclose the working area, including the title block and other tables on a drawing sheet. Traditionally, as per BIS, for the printed drawings the border is 20 mm wide on the binding edge (on the left-hand side of the drawing sheet) and 10 mm wide on the other three sides, with resulting working area sizes as shown in the below-provided image.
However, when drawings are stored in the electronic format, the wider border is not mandatory (as this is not required for binding) and can be 10 mm too for all sides.
TITLE BLOCK:
Title blocks are used to record all important information necessary for the working drawings. They contain general as well as specific information and it's mandatory to draw a title block on every working drawing sheet.
The title block is normally located in the lower right-hand corner of the drawing sheet.
The size of the title block as recommended by the B.I.S. is 185 mm (Width) x 65 mm (Height) for all designations of the drawing sheets.
There are two examples of different layouts of Title Block as per BIS, shown below.
Layout-1 (Title Block as per BIS)
However, the data may differ from company policy or the drawing at the industry level. The form and information vary from company to company. As an example, a company that produces castings has a large Title Block and may have different notes than a company that makes small tools and dies. See below examples of title blocks used in industries.
Example-1: Large job production companies have large Title Block Layouts.
Example 2: Small job production companies use a small Title Block Layout.
For the above-mentioned reason, the size of the Title Block has become optional and varies from company to company. Thus, it varies from college to college as well, on their own verified layout of Title Block, simplified for the students and guided by the teachers. So, always ask and take guidance about the layout from the respective teacher before you draw a Title Block on your drawing sheet. See below layout examples of the Title Block used in schools and colleges only.
Example - 1
Example - 2
INFORMATION ON THE TITLE BLOCK:
Though the size and layout of the title block are voluntary, a Title Block is always drawn on the right-hand bottom side of a drawing sheet and the following information is considered compulsory.
1. Drawing number,
2. Title or description of the drawing (part name),
3. Name of company/ institution (address, design affiliation – title or sheet number, etc.),
4. Scale or Scale ratio (Whether drawing is done on 1:1 or full scale, 1:2 or half scale, etc. (Read the article on Scale to get a better view).
If there is more than one scale on a single drawing sheet, the main scale only should be mentioned on the title block. All other scales should be shown near the detailed drawings on the sheet.
5. General specifications and notes ( tolerances, etc.),
6. Drafter name, area, approval signature, etc.
Besides these above data, title blocks may contain the following too especially for Company or Industrial Drawings...
1. Projection (Whether drawings are done on 1st angle projection or 3 angle projection. You can read about projection in detail here!).
2. Design approval when subcontractors are used.
3. Operations need to be done on the workpiece to finish the project.
4. Drawing paper size and designation.
5. genuine or estimated weight of the item.
6. Sheet number if there are multiple sheets in the set.
7. Date of issue.
8. Date of review or revision in block diagram.
9. Signatures.
10. Professional seals.
11. Job, order, or contract number.
12. References or other documents or file number.
13. Federal supply code for manufacturers ( FSCM) number.
The layout of the Title Block on a drawing sheet should be done in such a manner that it can be read easily and speedily.
RULES FOR 'SELECTING TITLES' OF THE DRAWING SHEET:
The proper selection of the title of the drawing sheet is veritably important. The title of the drawing sheet should be as brief as possible.
Describe the item shown in the drawing and should properly distinguish between similar items.
1) The title shall be the item name, which may consist of a noun or a sequence of words having a specific meaning (Phrase, noun expressions, modifier words). The noun or phrase shall describe the item and the use of the item, but not the material used or method of operations.
The terms IRON, HSS, CASTING, FORGING, WELDED, MACHINING, etc. shall not be used in the title as these express the material used or method of operation.
2) When selecting a title for a drawing sheet, try to avoid a similar name or always distinguish between items having a similar name to minimize confusion. The other modifier must always express a different characteristic from the first modifier. Some other modifier words are ASSEMBLY, SPECIAL PURPOSE, etc.
Example-1: 3/4x2 SHOULDER SCREW, 80 TEETH.
Example 2: Assembly of IMPELLER MAGNET AND CASING.
3) The words “ or ” and “ for ” shall not be used in the title of the drawing sheet.
Not granted example: LEVER FOR WEIGHT LIFTING.
Granted example: WEIGHT LIFTING LEVER.
4) No abbreviations or short form of any portion of the title shall be made, except those necessarily used for trademarked names, and the selected modifier words ASSEMBLY( ASSY), SUBASSEMBLY( SUBASSY), and INSTALLATION( INSTL).
Not granted example: IR Panther 720
Granted example: Industrial Robot Panther 720.
Granted example: SRMB Ingot.
5) An unclear noun or one that means several particulars shall not be used alone or as a modifier, but shall always be used as part of a phrase.
Granted example: JUNCTION BOX WIRING HARNESS
Not granted: JUNCTION HARNESS, WIRING, BOX
REVISION TABLE:
A drawing sheet may carry a revision table or a change table, generally seen on industry drawing sheets. According to the position, the revision table can be of two types.
a) Vertical Revision Table.
b) Horizontal Revision Table.
A revision table is either placed preferably on the right-hand side of the drawing sheet, above the title block, or at the bottom of the drawing sheet on the left from the title block.
In addition, the revision symbol, zone location, issue number, date, a brief description of the drawing revisions or changes, and approval of the revision may be made on the revision table and thus it's required on the drawing sheet for better recordings.
NOTES:
Notes are used to make or complement the graphic design by indicating information on a drawing shortly and methodically.
According to the position, there are two types of notes...
1. General Notes, and
2. Original Notes.
General Notes are notes that relate to the part or the whole drawing. General notes should be shown in a central position below the drawing to which they apply, or in a general note column.
Typical examples of general notes:
a) All Circles R9,
b) Tolerances apply after plating.
Original Notes apply to original conditions only and are always connected by a leader line to the point at which the note applies.
Typical samples of original notes:
a) Ø15 × 4 holes,
b) Chamfer 4 × 45 °
Common rules for all types of Notes:
1. Notes should be stated in the present tense, and in either imperative or permissive mood as needed.
2. Always avoid Lengthy, complex, or indefinite notes.