ENME152
Machine Drawing
Syllabus
- Limit Dimensioning and Machining Symbols (2 hours)
- Limit-fit system: basic terminologies, tolerances and methods of placing tolerances on a drawing, fit and types/systems of fit, ISO system of limits and fits, selection and calculation of limits, fits and tolerances
- Geometrical tolerances: basic terminologies, symbols of geometric tolerances and placement on a drawing
- Surface roughness and machining symbols: surface quality and roughness profile, surface roughness number and machining symbols, roughness grade number and grade symbols, symbols for direction of lay
- Threads, Bolts, Studs and Nuts (2 hours)
- Thread terms and nomenclature, forms of screw threads
- Detailed and simplified representation of internal and external threads
- Thread dimensioning
- Standard bolts and nuts: hexagonal head and square head
- Studs
- Locking devices
- Screws
- Washers
- Bolts and nuts for special applications
- Welding and Riveting (2 hours)
- Riveted joints: rivet and riveting, forms of rivet heads, types of riveted joints, terms associated with riveted joint
- Welded joints: welding and types of welded joints, welded joints symbols, specification of welded joints on drawing
- Pipe Joints (2 hours)
- Pipe and pipe materials
- Pipe designation
- Pipe threads
- Types of pipe joints
- Valves
- Piping symbols
- Piping layouts: single line and double line layouts
- Detail and Assembly Drawings (4 hours)
- Introduction to working drawing
- Components of working drawing: drawing layout, bill of materials, drawing numbers
- Detail drawing
- Assembly drawing
- Practices of detail and assembly drawing: V-block clamp, centering cone, couplings, bearings, antivibration mounts, stuffing boxes, screw jacks, tool post, expansion joint, turn buckle, coupling puller, vice, C-clamp, tail stock
- Basic Drawing Commands (2 hours)
- Loading software, screen organization
- Entering commands: menus, command line, function keys
- Commands and system variables
- Coordinate system: entering distances and angles
- Basic drawing commands: creating point, straight line and construction line, circle, arc and ellipse, polygons, splines
- Modifying Commands (2 hours)
- Erasing the object
- Creating multiple objects
- Scaling the object
- Creating chamfer and fillet
- Trimming and extending of the object
- Breaking and dividing
- Modifying colors, styles, etc. of the object
- Drawing Aids and Tools (2 hours)
- Setting up units and limits
- Using ortho, grids and snap
- Help and undo commands
- Display commands
- Creating isometric drawing
- Fine Tuning Drawings and Grouping (2 hours)
- Hatching command
- Working with layers
- Creating and inserting blocks
- Annotations and Dimensions (2 hours)
- Inserting text on drawing
- Dimension styles, dimensioning commands, tolerance, limits, dimension setup, dimension variables, dimension scale
- Three Dimensional Drawing (6 hours)
- Wireframe, surface and solid modeling
- Creating 3D drawing using thickness and elevation commands
- Solid modeling, standard
- Creating 3D drawing using extrude command
- Standard solid editing commands
- 3D modifying commands: move, rotate, mirror, array
- Shading and rendering and their options, motion path animations
- Plotting Drawings (2 hours)
- Layout management
- Plotting 2D and 3D drawings
- Creating multiple views for a 3D drawing
Practicals
- Limit, fit, tolerances and surface roughness and machining symbols
- Threaded joints
- Welded and riveted joints
- Pipe joints
- Detail drawing
- Assembly drawing
- 2D drawing consisting of straight lines, circle and arc
- 2D drawing consisting of ellipse and polygon
- 2D drawing using modifying commands
- Creating isometric, creating hatch, working with layers and blocks
- Inserting text and dimensions of 2D drawing
- 3D drawing: wireframe, surface and solid modeling
- 3D drawing: solid editing and 3D operations
- Plotting 2D and 3D drawings
- Project 1: drawing of standard mechanical components (spring, nut bolt, gear, cam profile, etc.)
- Project 2: detail drawing
- Project 3: assembly drawing
Evaluation
Final exam questions cover all chapters. Approximate marks distribution (total 40 marks over 30 hours):
- Limit Dimensioning and Machining Symbols: 6 marks
- Threads, Bolts, Studs and Nuts: 6 marks
- Welding and Riveting: 6 marks
- Pipe Joints: 6 marks
- Detail and Assembly Drawings: 16 marks
- Chapters 6 to 12 (computer aided drafting): covered only during internal evaluation