Mechanical Technology Automotive NSC Grade 12 Flashcards

Vocabulary flashcards covering core concepts, components, definitions, and formulas from the Grade 12 Mechanical Technology (Automotive) exam paper.

Code of Good Practice on HIV/Aids and Employment

A document containing common guidelines on how employers, employees, and trade unions should respond to HIV/Aids in the workplace.

Power-Driven Guillotine Finger Protector

A safety feature designed to prevent operators from reaching below the hold-down guards.

Hardening Temperature

The required temperature level during heat treatment, which depends directly on the carbon content of the steel.

Heat Treatment Steel Properties

The specific mechanical properties obtained in steel during heat treatment, determined by the type of grain structure.

Power

The rate at which work is done.

Swept Volume ($SV$)

The volume displaced by the engine piston as it moves from bottom dead centre ($BDC$) to top dead centre ($TDC$).

Clearance Volume ($CV$)

The space or volume remaining above the piston crown when the piston is at top dead centre ($TDC$).

Park ($P$) Position

The gearshift position in an automatic gearbox that engages a parking lock mechanism to prevent the vehicle from rolling.

Torque Converter Stator

A component within a torque converter that redirects fluid flow to increase the output torque produced by the engine.

Crankshaft Positioning Sensor ($CKP$)

An electronic sensor that detects and signals the position and rotational speed of the crankshaft to the electronic control unit ($ECU$).

Indicated Power ($IP$)

The total theoretical power developed inside the engine cylinder(s) by the burning air-fuel mixture.

Brake Power ($BP$)

The actual usable mechanical power measured at the engine crankshaft or output shaft.

Compression Ratio ($CR$)

The ratio of the total cylinder volume ($SV + CV$) to the clearance volume ($CV$), expressed mathematically as $\frac{SV + CV}{CV}$.

Case Hardening

A heat treatment process used to produce a hard outer surface layer on low-carbon steel while maintaining a tough, ductile core.

Normalising

A heat treatment process performed on steel to relieve internal stresses and restore or refine its natural grain structure.

Mechanical Efficiency

The ratio of brake power ($BP$) to indicated power ($IP$), calculated as $\frac{BP}{IP} \times 100$.

Adaptive Speed Control

An automated driver-assistance feature designed to maintain a set vehicle speed while adapting to preceding traffic conditions.

Common Rail Direct Injection ($CRDI$) High-Pressure Pump

A component in a $CRDI$ system responsible for delivering fuel under extremely high pressure to the common fuel rail.