Mechanical Technology Welding and Metalwork Memo 1 (English)

November 2022 — Grade 12 / Matric — Mechanical Technology

Memo 2022 Grade 12 English

↓ Download PDF 📄 380.6 KB View Exam Paper

Preparing document

📋 Document Analysis

🎯 200 marks 📄 8 pages 📝 121 items found 📚 2 topics

See full analysis

Questions — A Preview of What to Expect in the Document

121

This section provides a quick preview of questions from the document. It may not display every question or the complete wording of each one. For the full content, including diagrams, tables and other information, view the original PDF above.

Q1— Section header —

1.1(1\

1.2(1\

1.3(1\

1.4(1\

1.5(1\

1.6(1\ [6] Mechanical Technology: Automotive DBE/November 2022 NSC Marking Guidelines Copyright reserved6

Q2— Section header —

2.1Vital functions: Breathing Heart rate / pulse State of consciousness (Any 2 x 1\ (2\

2.2Safety glasses during grinding: To prevent any injuries to the operator's eyes. To protect eyes from sparks and debris. To prevent blindness due to injury (Any 1 x 1\ (1\

2.3Type of guards: Fixed guard Automatic sweep away Self adjusting / automatic guard Electronic presence sensing device

2.4Precautions before gas welding operations can be undertaken: An operator has been instructed on how to use the equipment safely. A workplace is effectively partitioned off. An operator uses protective equipment (PPE\

2.5TWO disadvantages of the product layout: Lack of flexibility. Optimum use of equipment is not possible. (2\ [10] Mechanical Technology: Automotive DBE/November 2022 NSC10

Q3— Section header —

3.1THREE properties: Toughness Hardness / Wear resistance Softness Case hardness Ductility Malleability Elasticity

3.2Heat treatment processes

3.2.1Tempering: It consists of heating the hardened steel to a temperature below its critical temperature (colour chart\. Soaking it at this temperature for a period of time, Quenching/cooling it rapidly in water, brine or oil.

3.2.2Hardening: The steel is heated slightly higher than the upper critical temperature. The steel is soaked at that temperature for the required time. The steel is then rapidly cooled by quenching in water,

3.3Examples of case hardening: Bearing cases Bearing ball Bearing needles Crankshafts Gears Camshafts

3.4Why steels are cooled down in still air away from draughts: This prevents sudden cooling of localised spots, which might cause distortion /cracks. (2\ [14] Mechanical Technology: Automotive14

Q4— Section header —

4.1(1\

4.2(1\

4.3(1\

4.4(1\

4.5(1\

4.6(1\

4.7(1\

4.8(1\

4.9(1\

4.10(1\

4.11(1\

4.12(1\

4.13(1\

4.14(1\ [14] Mechanical Technology: Automotive DBE/November 2022 NSC Marking Guidelines Copyright reserved14

Q5— Section header —

5.1Compression test:

5.1.1The ignition system is disconnected: To prevent a shocking hazard to the operator. To prevent fire hazard. Prevent any sparks / flow of current from the ignition system (Any 2 x 1\

5.1.2All spark plugs are removed: To ensure accurate readings. To allow the engine to swing easier. To fit the compression tester. (Any 2 x 1\ (2\

5.1.3Removing the air filter: To allow maximum air flow into the cylinder. To ensure accurate readings (2\

5.2Cylinder leakage tester: Connect the compressed air hose from compressor to the tester. Adjust the regulator valve knob and observe the gauge needle. Stop turning the knob when the gauge is on 0%. (3\

5.3Exhaust gas analyser: Analyse exhaust gasses Indicate the amount of CO, CO , HC, NO , SO

5.4OBD scanners: Bluetooth Wi Fi Cable (3\

5.5Static wheel balance and dynamic wheel balance: Static balancing refers to the wheel s balance as it becomes

5.6Wheel imbalance The plane of imbalance / he imbalance is on the inner or outer side of the wheel. The extent of the unbalancing forces / The mass of the balancing weights.

5.7Optical alignment: Look through the periscope gauge. Align the vertical line through the triangle by moving the pointer arm. Take the degree reading on the toe gauge. Note if the reading is on the IN or the OUT

Q6— Section header —

6.1Crankshaft ndirectly rives: Camshaft Distributor il pump

6.2Vibration dampers

6.2.1Combined rubber and friction disc (1\

6.2.2The friction face type (1\

6.3Features that improve engine balance: The crankshaft is carefully balanced / Counterweights on the crankshaft. Connecting rods and pistons are kept as light as possible Flywheels are carefully balanced

6.4type engine advantages: Can be mounted in smaller engine compartments. The engine is shorter in length. Improved power to weight ratio. Lighter mass. Improved fuel efficiency.

6.5Four cylinder firing orders:

6.6Position of crankpin:

6.6.1cylinder (1\

6.6.2cylinder cylinder (Any 1 1\

6.6.3cylinder cylinder (Any 1 x 1\ (1\

6.7.1Labelling the turbocharger: A. Compressor outlet Air outlet B. Compressor /

6.7.2Types of turbochargers: Non variable type turbocharger Varia ble geometry turbocharger (VGT\ Single turbocharger Twin turbocharger Twin

6.7.3Idling before turning the engine off: Allows the turbo charger to slow down o cool down the turbo charger components. To ensure

6.8uperchar gers:

6.8.1Centrifugal supercharger (1\

6.8.2Roots supercharger (1\

6.8.3Twin screw supercharger (1\ [28] Mechanical Technology: Automotive 11 DBE/November 2022 NSC28

Q7— Section header —

7.1Swept volume: The volume displaced by the piston during a stroke (BDC to TDC\ (2\

7.2Work:

7.2.1(3

7.3Cylinder:

7.3.1 A. Bore / Cylinder iameter B. Stroke length (2

7.3.2 Swept volume: 120 mm = 12 cm 135 mm = 13,5 cm OR

7.3.3 Compression ratio (CR\ OR (3

7.4Calculate Indicated power (7\

7.5ynamometer to measure brake power Prony brake Electric dynamometer Eddy current

7.6Calculations

7.6.1 Torque (4

7.6.2 Brake power (3\

7.6.3 Mechanical efficiency (2\ [32] 1200 10 12032

Q8— Section header —

8.1Gas analyser: High carbon monoxide (CO\ High oxygen (O High itro gen oxides

8.2Cylinder leakage test Listen for hissing sound at the air intake. Listen for hissing sound at the exhaust pipe. Listen for hissing sound in the dipstick hole / oil filler cap Look for bubbles in the radiator water.

8.3Compression test

8.3.110% (1\

8.3.2OR (2

8.3.3Low Compression Worn compression rings Worn piston Worn cylinder

8.3.4Corrective measure Repair or replace cracked cylinder head Reset or replace or adjust the valves Replace cylinder head gaskets

8.4Causes of a low oil pressure Worn oil pump Blocked oil pump/ creen in sump

8.5Corrective measures with oil if the oil pressure reading is high Use the correct oil grade Change the oil with clean oil. (2\

8.6Pre checks fuel pressure tester: Ensure that the tester can read the pressure of the engine. Use the right adaptor for the engine. Ensure that the rubber pipe is not perished on the tester. Ensure that the pressure relieve valve is working properly.

8.7Cooling system pressure test: Renew the gaskets or seals Renew the faulty water hose ecure water hose

Q9— Section header —

9.1Double epicyclic gear system: 9.

1.1Labels A. Input shaft /Sun gear shaft B. Brake band

1.2Operation of this gear system: Sun gears are driven by the input shaft (A\ Annu lus (C \eld stationary by its brake bands (B Planetary g

2.1One way clutch on the stator (1\ 9.

2.2Turbine (1\ 9.

2.3Stator (1\

9.2.4Impeller (1\

9.3Oil used in the torque converter: ATF or Automatic transmission fluid (1\

9.4Advantages of epicyclic gear trains The c axial arrangement of input shaft and output shaft Load distribution is to several planetary gears

Q10— Section header —

10.1Tyre wear

10.1.1Over inflation Excessive wear in the middle of the tyre (1\

10.1.2Negative camber Excessive wear on the inside edge or inside shoulder of the tyre. (1\

10.2Purpose of wheel alignment angles

10.2.1Toe in Toe in is used to o vercome the tendency of wheels

10.2.2Negative caster Negative caster ensures easier turning (2\

10.3King pin inclination

10.3.1Labels A. King pin inclination angle / KPI / Steering axis inclination

10.3.2Definition King pin inclination is the inward tilt of the top of the king pin (2\

10.3No (1\

10.4Unbalanced wheels Shimmy / wobble ounce Vibration on steering Poor steering control Tyres wear away faster

10.5Air intake sensors Throttle position sensor (TPS\ Idle speed control (ISC\ Manifold absolute pressure (MAP\

10.6Function of the speed control system: To control the throttle opening electronically. To keep the vehicle at a constant speed. (2\

10.7Alternator

10.7.1Label A. Slip ring B. Brushes C. Pole pieces (3

10.7.3Methods to increase the out put frequency of the alternator: Increase the turns of wire / windings on the stator. Increase the amount of magnetic poles. Increase the rotational frequency of the rotor.

10.8Catalytic converter Oxidation Reduction (2\

10.9Label piezo injector A. Fuel intake/ inlet B. Nozzle pray

10.10Functions of the check valve: It maintains the pressure in the fuel. Prevents vapour lock. Ensures easier starting. (Any 2 x 1\ (2\ [32] TOTAL: 20032

Topics Identified

CircuitsConstruction

Mark Allocation

Total200 marks

Sections6 + 10 + 14 + 14 + 23 + 28 + 32 + 23 + 18 + 32 = 200 marks

Paper information

SubjectMechanical Technology

Year2022

SessionNovember

TypeMemo

PaperPaper 1

LanguageEnglish

Pages18

Downloads6

Examination context

Decade2020s

Years ago4y

SeasonSpring (SH)

Start daySaturday

Exam periodNovember 2022

Days since exam1,448

About Mechanical Technology examination preparation

This Grade 12 examination resource can be used as part of a structured revision programme. Past papers are most useful when learners attempt questions independently, work within a realistic time limit, and review their answers afterwards.

How to use this resource for revision

A past examination paper is most useful when it is treated as an active revision exercise. Try the questions yourself before checking the corresponding memorandum. Where you make an error, identify the reason — was it a knowledge gap, a calculation mistake, an interpretation issue, or an examination technique problem?

For stronger examination practice, complete the paper without unnecessary interruptions and keep track of the questions that take the most time. Afterwards, review the memorandum and separate knowledge gaps from mistakes caused by interpretation, calculation, structure, or examination technique.

understanding question requirements

applying subject knowledge

working under time constraints

checking answers

identifying revision priorities

A practical revision approach

Start by completing the resource without looking at the memorandum. Review incorrect and incomplete answers afterwards and make a short revision list based on the areas that caused difficulty.

Grade 12 subject hubs

Each matric subject has its own dedicated hub on Freemode with every past paper and marking memorandum we have archived for that subject.

➗ Mathematics View papers → 📊 Mathematical Literacy View papers → ⚗️ Physical Sciences View papers → 🧬 Life Sciences View papers → 📒 Accounting View papers → 💼 Business Studies View papers → 📈 Economics View papers → 🌍 Geography View papers → 🏛️ History View papers → 📖 English View papers → 🇿🇦 Afrikaans View papers → 🗣️ IsiNdebele View papers → 🗣️ IsiXhosa View papers → 🗣️ IsiZulu View papers → 🗣️ Sepedi View papers → 🗣️ Sesotho View papers → 🗣️ Setswana View papers → 🌾 Agricultural Sciences View papers →

Corresponding examination paper

Examination paper available

Open the corresponding examination paper to practise the questions before reviewing the marking memorandum on this page. Attempt every question under timed conditions for the most realistic preparation.

Mechanical Technology Welding and Metalwork Paper 1 (English) →

File details

File size380.6 KB

Pages18

Archived on11 October 2026

File age12d

ContributorFreeMode

FingerprintD4DAB15E89D4

Questions and learner discussion

No questions or discussions have been posted yet.