SAMPLE. Interpret technical drawing. (Fabrication Edition) MEM09002B. Learner guide. MEM05 Metal and Engineering. Training Package.

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1 MEM05 Metal and Engineering Training Package MEM09002B Interpret technical drawing (Fabrication Edition) Learner guide Version 1 Training and Education Support Industry Skills Unit Meadowbank Product code: 2759

2 Acknowledgement The TAFE NSW Training and Education Support Industry Skills Unit, Meadowbank would like to acknowledge the support and assistance of the following people in the production of this learner resource guide: Introduction CONTENTS Writers: Jim Miles 1. General introduction Using this learner guide... 6 Reviewers: Steve Bennetts Tony Cartwright Phil Myers John Sharples Neil Smith Ed Zussa 3. Prior knowledge and experience Unit of competency overview Assessment... 9 Project Manager: Stephen avies Education Programs Manager TAFE NSW Enquiries Enquiries about this and other publications can be made to: Training and Education Support Industry Skills Unit, Meadowbank Meadowbank TAFE Level 3, Building J, See Street, MEAOWBANK NSW Student assessment guide... 9 Topics Topic 1 rawing work, standards and standard drawing sheets Topic 2 rawing types - recognition Topic 3 Line types - identification Topic 4 Pictorial presentations Topic 5 rawing presentation Topic 6 Sectioning standards and conventions - recognition Tel: Fax: The State of New South Wales, epartment of Education and Training, TAFE NSW, Training and Education Support Industry Skills Unit, Meadowbank, Copyright of this material is reserved to TAFE NSW Training and Education Support Industry Skills Unit, Meadowbank. Reproduction or transmittal in whole or in part, other than for the purposes of private study or research, and subject to the provisions of the Copyright Act, is prohibited without the written authority of, TAFE NSW Training and Education Support Industry Skills Unit, Meadowbank. Topic 7 Feature representations - recognition Topic 8 imensioning identification Topic 9 imensioning features recognition and interpretation Topic 10 Symbols used in fabrication industries Topic 11 Revision and review questions ISBN eveloped by Training & Education Support Industry Skills Unit, Meadowbank TAFE NSW 2010

3 Topic 1 : rawing work, standards and standard drawing sheets Standard rawing Sheets Size Reminder: To demonstrate competence at the end of this topic you will be able to: Identify the main features of an engineering drawing sheet and state their purpose Recognise methods of presenting engineering drawings and layouts There are five (5) preferred sizes ranging from A0, being the largest, to A4, the smallest. As you go from A0 to A4, each sheet is half the area of the previous one. The area of A0 is 1 square metre. Comparative sheet sizes are shown below. A0 Producing drawings rawings are produced on standard sized sheets, ranging from A0 to A4. rawings may be made in three ways: freehand sketching by hand with drawing instruments such as ruler and compass computer assisted using computer software to produce the drawing (computer aided drafting - CA) Copying or reproducing drawings epending on size, drawings are normally reproduced by: photocopying computer plotting computer print-out rawing standards Note: A1 A2 Metric Sheet Size System There is a number of relationships that arise from this system: A4 Engineering drawings have to be done so that all tradespeople and engineers can interpret them against recognised standards or conventions. rawings are made to a standard so that they: use the same symbols, lines, dimensioning techniques etc can be understood in different work locations, around Australia and the world The ratio of the length to the breadth of all sheets is 2:1 (square root of 2:1) The length of one size is equal to the breadth of the next size up (and vice versa) To work out length of one size up just double the breadth of the smaller size (and vice versa) The dimensions of the sheet two sizes up, are double eg A2 is double the length and breadth of A4 (and vice versa) The drawings in this unit should be on standard sized sheets as stated in AS1100. There are several drawing standards available both nationally and internationally. For this resource all our drawings comply with: So, once you know one dimension of any size (eg A4 is 297 mm long), you can easily work out the rest. Australian Standard Technical rawing Part General Principles Page 11 of 152

4 Borders The suggested border is proportional in size to the size of the sheet. In the example below the borders on an sheet are larger than those on an A4 sheet, and so on up to A0 7 A (283) 20 5 (200) 5 28 (400) 7 7 (283) 7 (566) A (400) 10 (801) A1 14 (1133) 14 (566) A0 20 (801) Sheet imensions Margin imensions Note: Sheet Size imensions of Sheet A4 210 x x 420 A2 420 x 594 A1 594 x 841 A0 841 x 1189 Sheet Size Top & Bottom Both Sides imensions of rawing Frame A x x 400 A x 566 A x 801 A x 1133 The relationship between the dimensions noted on previous page still applies (approximately). Preferred Metric Sheet Sizes Page 12 of 152

5 Title block information The title block identifies a range of information relating to the drawing. It includes: name of the company title of drawing drawing sheet number (for storage and reference purposes) who prepared the drawing who checked the drawing other important information regarding the drawing, such as a history of any changes that have been made since the drawing was originally prepared. NOTE: Each company generally has its own format for title blocks. A B C ISSUE MEM09002B Interpret technical drawing (fabrication edition) NOT TO SCALE ALL IMENSIONS IN MILLIMETRES Numbers and letters are used for easier location e.g. Zone B2 B2 OF A STANAR SHEET LAYOUT WITH A BLANK BLOCK THE LAYOUT VARIES FROM ORGANISATION TO ORGANISATION UNLESS NOTE OTHERWISE TOLERANCES ARE: LINEAR MATERIAL RAWN CHECKE APPROVE ISSUE ATE ZONE CHANGE AMENMENTS 1 2 BY CK ANGULAR RAWING PRACTICE AS FINISH 4 A: RECOR OF ISSUE SCALE 5 SIZE RG Nº SHT 6 Page 13 of 152 A B C

6 Parts of a title block Size, Scale and rawing Number The next few pages will explain what information is conveyed by each part of a title block. The drawing number or sheet number may be abbreviated to either RWG No or WG No and SHT No. The name of the company Each company designs its own title block and has quantities of each size of drawing sheets printed. The above designation has been used as an example. EXHAUST UCT UCTING ETAILS UNLESS NOTE OTHERWISE TOLERANCES ARE: LINEAR ANGULAR MATERIAL RAWN CHECKE APPROVE ISSUE RECOR OF ISSUE RAWING PRACTICE FINISH A: SCALE SIZE RG Nº AS EXHAUST UCTING ASSEMBLY Title A description of what is drawn on the sheet eg component name, or assembly Below are two examples UNLESS NOTE OTHERWISE TOLERANCES ARE: LINEAR ANGULAR RAWING PRACTICE AS 1100 MATERIAL RAWN CHECKE APPROVE ISSUE RECOR OF ISSUE FINISH A: SCALE SIZE RG Nº NTS EXHAUST UCT UCTING ETAILS SHT 1 SHT 3 SCALE SIZE RWG Nº. SHT of 3 Sheet Number (SHT) is optional. Every sheet in a set of drawings for a particular device or assembly is numbered rawing Number (RWG No or RG No). This number is a number given by the company to a particular drawing or set of drawings for something to be constructed. Where sheet numbers are not used drawing numbers are usually in sequence, for example 1010, 1011, 1012, etc. Size refers to the original sheet that the drawing was drawn on. It is not necessarily the size of the sheet you are looking at because you may be looking at a copy that has been reduced or expanded. Scale. Not all components or constructions are drawn full size. eg. The plans for a house are not drawn full size for obvious reasons. Hence, large objects are drawn to reduced scale such as ½ full size (1:2), 1/10 full size (1:10) etc. UNLESS NOTE OTHERWISE TOLERANCES ARE: LINEAR ANGULAR RAWING PRACTICE AS 1100 MATERIAL RAWN CHECKE APPROVE ISSUE RECOR OF ISSUE FINISH A: SCALE SIZE RG Nº EXHAUST UCT FAN SUPPORT SUB-ASSEMBLY NTS SHT 2 The scale box for full sized drawings is usually marked 1:1 or full size. A half size drawing would be marked 1:2, a 1/10 full size 1:10 and so on. On the other hand, very small components are sometimes drawn larger than full size. eg twice full size would be marked as 2:1, five times full size would be marked 5:1 and so on. It is also common to use NTS (not to scale) Note: Even when a scale is quoted, drawings in this resource may vary from that scale. Page 14 of 152

7 This section provides reference material which you may need to refer back to while completing this unit. rawn, Checked, Approved, Issued and Record of Issue (Refer to samples on previous pages) SPECIAL NOTE: Traced Older style drawings may still have a box labelled Traced. Tracing has now virtually been replaced by CA. rawn (Zone 4) The drafter places either their name or initials in this box. Projection symbols Checked (Zone 4) The person who checks the drawing for accuracy, errors, correct quantities, spelling, safety considerations etc. places their name or initials in this box. Approved (Zone 4) A senior engineer is often the one who goes over the drawings for another opinion and safeguard. They then sign or initial this box. Issued (Zone 4) This is the date when, after thorough checking, the drawings are issued to the workshop or subcontractors are permitted to commence construction or tenders are called for. Record of issue (optional) (Zone 4) On the sample sheet there are ten small squares for this function. The first issue is A. If any changes or modifications are carried out, this is noted in the amendments box as a later issue B, C, etc. The drawings then have to be re-issued with the amendment shown as issue B. All issue A drawings, must be archived or even destroyed. Any previous A issue drawings that are now incorrect and remain in the system could cause catastrophic problems in production. It is very obvious that, before making anything, it is critical to ensure that the drawings being used are the latest issues. Old drawings that have been on the bench, under the bench, or in drawers for months, or years, pose a real threat to industry. All these potential problems can be resolved by making a simple phone call to the drawing office in most cases. Otherwise, if any doubt exists, a check should be made with your immediate supervisor. First Angle Third Angle The two symbols shown above represent two methods of placing views on a drawing. Even though Third Angle is preferred on standard engineering drawings in Australia, some industries still use First Angle. It is important that both systems are understood to avoid costly and embarrassing errors during fabrication. On some drawings, even an experienced drafter has to look carefully to determine which system has been used. A comparison between first angle and third angle is demonstrated in the next page using a car as an example. As an aid to memorise which is which, remember the phrase: Third Angle - This side, First Angle - Far side Material (Zone 4) This box is for listing the types of material that the fabrication is made from. Often a number of parts made from different materials are drawn on the same sheet, in which case the type of material will have to be noted under each part. Note: In many older drawings you will see some material indicated as MS (Mild Steel). It is now common practice to use LCS (Low Carbon Steel) instead. Finish (Zone 4) The designer of any machined part may have to determine how smooth each surface has to be. Most component surfaces often need to have a range of different surface finishes on them. If the object is basically the same all over the surface finish is placed in the box followed by the letters UNO (unless noted otherwise) Page 15 of 152

8 First Angle Projection Third Angle Projection rawn below is a practical example of first angle projection. Note that the views are projected to the opposite side from where you are looking. Below is a practical example of third angle projection. Note that the respective view is projected to the same side from where you are looking. Projection symbol Projection symbol Bottom view E (Underneath of car) A B C A Right end view C (Back of car) E Front view A (Side of car) Left end view B (Front of car) Left end view B (Front of car) B A Top view (Top of car) E Front view A (Side of car) A C Right end view C (Back of car) Top view (Top of car) Bottom view E (Underneath of car) Note: All drawings in this resource will use third angle projection Page 16 of 152

Electrotechnology Workshop Tools and Techniques SAMPLE. Learner Workbook. Version 1. Training and Education Support Industry Skills Unit Meadowbank

Electrotechnology Workshop Tools and Techniques Learner Workbook Version 1 Training and Education Support Industry Skills Unit Meadowbank Product Code: 5636 Enquiries Enquiries about this and other publications