MEP210 Mechanical Engineering Drawing

Credits 3 (1-0-4)

• Dr. Ashish K Darpe– (III-176) Phone: 6095(O), 1618(R),

9911112446 (M)– akdarpe@mech.iitd.ac.in

• http://web.iitd.ac.in/~akdarpe/

SHEET LAYOUTS

Two Basic rules -

TITLE BLOCK

•The position of the title block should bewithin the drawing space such that the portion of the title block containing the identification of the drawing (registration number, title, origin, etc) is situated in the bottom right-hand corner of the drawing space, both for sheets positionedhorizontally (Type X) or vertically (Type Y). •The direction of the viewing of the title block should correspond, in general, with that of the drawing.

ITEM REFERENCE (Bill of Materials)

TYPES OF DRAWINGS

1. SINGLE PART DRAWING.2. COMMON DRAWING.3. ASSEMBLY DRAWING.4. WELDING DRAWING.5. CASTING DRAWING.6. FORGING.7. SHEET METAL.8. PIPING.9. CIRCUIT DIAGRAMS.10.PICTORIAL DRAWING.11.PLANT LAYOUTS.

•Exploded assembly drawing.•Schematic assembly drawing.•Drawing for installation.•Drawing for catalogue•Patent drawing.

•Imaginary lines of intersection.•Dimension lines.•Projection lines.•Leader lines.•Hatching, short center lines.

TYPES OF LINES:-

Visible outlines

General applications-

Continuous thick

Continuous thin

Continuous thinFreehand.

Limits of partial and Interrupted views

Continuous thinStraight with zigzag. Long break line.

Dashed thick.•Hidden outlines.•Hidden edges.

A

B

C

D

E

TYPES OF LINES:- General applications-

Dashed thin.•Hidden outlines.•Hidden edges.

Chain line•Center lines.•Lines of symmetry.•Line of trajectories.

Chain thin, thickat ends and changesthe direction

•Cutting planes.

Thick chain line

•Indication of lines or surfaces to which special requirement applies.

F

G

H

J

Lines Pencil

•Initial work and construction lines.•Outlines, dotted lines, section plane lines, dimension lines, arrowheads•Centre lines, section lines

H

2H

3H or 4H

TYPES OF LINES:-General applications-

Thin chained double Dashed.

•Outlines of adjacent parts.•Alternative and extreme positions of movable parts.•Centroidal lines.•Initial outlines prior to forming.•Parts situated in front of cutting plane.

K

A Continuous thick

B Continuous thin

C Continuous thin

Freehand

D Continuous thin

Straight with zigzag.

E Dashed thick.

F Dashed thin.

G Chain line

H Chain thin, thick

at ends and changes

the direction

J Thick chain line

K Thin chained double

Dashed

SECTIONS AND HATCHING

•Hatching is generally used to show areas of sections.•The simplest form of hatching is usually done by drawing continuous thin lines at a convenient angle, preferably 45º to the principal outlines or lines of symmetry of the sections.

•Separate areas of a section of the same component shall be hatched in an identical manner.•The hatching of adjacent components shall be carried out with different directions or spacing.

•Thin Sections - Thin sections may be shown entirely black a space of not less than 0.7 mm must be left between adjacent sections of this type.

Arrangement of Successive Sections

•Section of connecting rod.

•To save time and space, symmetrical objects may be drawn as a fraction of the whole

In cases where the scale is so small that details of the feature cannot be shown or dimensioned, the feature of the part may be framed by acontinuous thin line (type B) and identified by a capital letter