MANF 240 Constructional Details 19 March, 2011

Prof. Samy J. Ebeid ١

SJE Part 05 Constr. Details ١

Constructional Details

SJE Part 05 Constr. Details ٢

Different manufacturing processes such as:

-machining

-casting, die-casting

-forging

-RP

Different machining processes such as:

-course m/cg: turning, boring, milling, drilling, planing, spot facing.

-fine m/cg: turning, milling, grinding, honing, polishing.

Manufacturing Processes

Items to avoid during Casting

-high stress concentrations

-shrinkage cavities

-improper feeding of liquid metal

-non-uniform cooling

-sharp corners

-abrupt cross-sectional changes

MANF 240 Constructional Details 19 March, 2011

Prof. Samy J. Ebeid ٢

SJE Part 05 Constr. Details ٣

Castings Improvements

-No stress concentrations at corners

-avoiding porous areas

SJE Part 05 Constr. Details ٤

Castings Improvements

-Possibility of crack formation

-Better material flow during casting

MANF 240 Constructional Details 19 March, 2011

Prof. Samy J. Ebeid ٣

SJE Part 05 Constr. Details ٥

Castings Improvements

tmin, mmmetal

6Cast iron

Aluminium alloys

2Copper alloys

Magnesium

Cast steel

SJE Part 05 Constr. Details ٦

Castings Improvements

Casting Tapers

Casting Fillets

MANF 240 Constructional Details 19 March, 2011

Prof. Samy J. Ebeid ٤

SJE Part 05 Constr. Details ٧

Casting Thickness Flow

Castings Improvements

Casting Material at Junction

SJE Part 05 Constr. Details ٨

Machining Improvements

MANF 240 Constructional Details 19 March, 2011

Prof. Samy J. Ebeid ٥

SJE Part 05 Constr. Details ٩

Machining Improvements

SJE Part 05 Constr. Details ١٠

Machining Improvements

Use of chamfers

MANF 240 Constructional Details 19 March, 2011

Prof. Samy J. Ebeid ٦

SJE Part 05 Constr. Details ١١

Machining Improvements

SJE Part 05 Constr. Details ١٢

Machining Improvements

A clearance should be left for the run-out of

the tool

MANF 240 Constructional Details 19 March, 2011

Prof. Samy J. Ebeid ٧

SJE Part 05 Constr. Details ١٣

Machining Improvements

Blind hole Through holes

Too many machining surfaces

SJE Part 05 Constr. Details ١٤

Machining Improvements

Drilling on inclined surfaces is not recommended

Avoid inclined surfaces at tool exit

MANF 240 Constructional Details 19 March, 2011

Prof. Samy J. Ebeid ٨

SJE Part 05 Constr. Details ١٥

Machining Improvements

Need for reference surfaces for clamping on machine tools

during machining

SJE Part 05 Constr. Details ١٦

Machining Improvements

Centering spigots are needed for mating parts

Centering dowels are needed for bolted covers

MANF 240 Constructional Details 19 March, 2011

Prof. Samy J. Ebeid ٩

SJE Part 05 Constr. Details ١٧

Machining Improvements

SJE Part 05 Constr. Details ١٨

Machining Improvements

Poor fitting if straightness is a must

Chamfers at end of shafts

MANF 240 Constructional Details 19 March, 2011

Prof. Samy J. Ebeid ١٠

SJE Part 05 Constr. Details ١٩

Machining Improvements

Two-surface contact should be avoided

Two-surface contact should be avoided One-surface contact

SJE Part 05 Constr. Details ٢٠

Arch of base is subjected

to heavy flexureArch of base is reinforced by

internal ribs, working in tension

Arch of base is reinforced by external

ribs, working in compressionLug under plane of loading

– most light weight construction

Bearing Block

MANF 240 Constructional Details 19 March, 2011

Prof. Samy J. Ebeid ١١

SJE Part 05 Constr. Details ٢١

Casted Cover

Poor rigidity

Imp

rove

d d

esig

ns

SJE Part 05 Constr. Details ٢٢

Box-shaped cover fixed to a housing by a central stud

Poor rigidity.The cover

deflects when tightened.

Draw suitable solutions.

Box-shaped Cover

MANF 240 Constructional Details 19 March, 2011

Prof. Samy J. Ebeid ١٢

SJE Part 05 Constr. Details ٢٣

Flanged Shaft

Poor rigidity

Cup-shaped flange.

The transition section

“a” where the flange

joins the hub, is

strengthened.

Conical flange.

SJE Part 05 Constr. Details ٢٤

Bracket with Hub

Poor rigidity

Conical Design

Cup-shaped Design

Improved Conical Design

MANF 240 Constructional Details 19 March, 2011

Prof. Samy J. Ebeid ١٣

SJE Part 05 Constr. Details ٢٥

Centering Techniques

Reduction in centering diameter

SJE Part 05 Constr. Details ٢٦

Fitting on Several Surfaces

Fitting on Two surfaces

Fitting on One surface

MANF 240 Constructional Details 19 March, 2011

Prof. Samy J. Ebeid ١٤

SJE Part 05 Constr. Details ٢٧

Fitting on Several Surfaces

Fitting on Two surfaces

Fitting on One surface

Fitting on One surface

SJE Part 05 Constr. Details ٢٨

Fitting on Several Surfaces

MANF 240 Constructional Details 19 March, 2011

Prof. Samy J. Ebeid ١٥

SJE Part 05 Constr. Details ٢٩

Tapering of Flanges

SJE Part 05 Constr. Details ٣٠

Seats of Flanges

Large seat, more

machining is required

Acceptable seat, less

machining is required

MANF 240 Constructional Details 19 March, 2011

Prof. Samy J. Ebeid ١٦

SJE Part 05 Constr. Details ٣١

Machining Improvements

SJE Part 05 Constr. Details ٣٢

Machining Improvements

MANF 240 Constructional Details 19 March, 2011

Prof. Samy J. Ebeid ١٧

SJE Part 05 Constr. Details ٣٣

Prevention of sharp corners

Machining Improvements

Minimum machining

SJE Part 05 Constr. Details ٣٤

Design Factors

1. Stiffness

2. Strength

3. Thermal properties (thermal stresses)

4. Corrosion

5. Wear

6. Friction

7. Process of manufacturing

8. Use of the component

9. Cost

10. Safety

11. Noise and vibrations

12. Appearance of component

13. Shape and compactness

14. Size

15. Surface finish

16. Tolerances

17. Lubrication

18. Life