Mechanical Technology Grade 12 Gauteng June 2025 QP (Eng)

JUNE EXAMINATION JUNIE EKSAMEN GRADE/GRAAD 12 2025 MECHANICAL TECHNOLOGY: MEGANIESE TEGNOLOGIE: WELDING AND METALWORK SWEIS- EN METAALWERK TIME/TYD: 3 hours/uur MARKS/PUNTE: 200 16 pages + a 2-page formula sheet 16 bladsye en ʼn 2-bladsy formuleblad Please turn over Blaai asseblief om

MECHANICAL TECHNOLOGY: WELDING 2 AND METALWORK GR12 0625 INSTRUCTIONS AND INFORMATION 1. Write your name and surname on the ANSWER BOOK. 2. Read ALL the questions carefully. 3. Answer ALL the questions. 4. Number the answers correctly according to the numbering system used in this question paper. 5. Start EACH question on a NEW page. 6. Show ALL calculations and units. Round-off final answers to TWO decimal places. 7. Candidates may use non-programmable scientific calculators and drawing instruments. 8. The value of gravitational acceleration should be taken as 9,81 m/s2 or 10 m/s2. 9. All dimensions are in millimetres, unless stated otherwise. 10. Write neatly and legibly. 11. A formula sheet is attached to the question paper. 12. Use the criteria below to assist you with your time management. TIME QUESTION CONTENT MARKS IN MINUTES GENERIC 1 Multiple-choice Questions 6 10 2 Safety 18 10 3 Materials 14 10 SPECIFIC 4 Multiple-choice Questions 14 14 5 Terminology (Templates) 32 25 6 Tools and Equipment 31 25 7 Forces 40 40 8 Joining Methods (Inspection of Welds) 18 26 9 Joining Methods (Stress and Distortion) 27 20 TOTAL 200 180 Please turn over

MEGANIESE TEGNOLOGIE: SWEIS- EN 2 METAALWERK GR12 0625 INSTRUKSIES EN INLIGTING 1. Skryf jou naam en van op die ANTWOORDBOEK 2. Lees AL die vrae aandagtig deur. 3. Beantwoord AL die vrae. 4. Nommer die antwoorde korrek volgens die nommeringstelsel wat in hierdie vraestel gebruik word. 5. Begin ELKE vraag op 'n NUWE bladsy. 6. Toon ALLE berekeninge en eenhede. Rond finale antwoorde tot TWEE desimale plekke af. 7. Kandidate mag nie-programmeerbare wetenskaplike sakrekenaars en tekeninstrumente gebruik. 8. Die waarde van gravitasieversnelling moet as 9,81 m/s2 of 10 m/s2 geneem word. 9. Alle afmetings is in millimeter, tensy anders vermeld in die vraag. 10. Skryf netjies en leesbaar. 11. 'n Formuleblad is aan die vraestel aangeheg. 12. Gebruik die kriteria hieronder om jou met jou tydsbestuur te help. TYD VRAAG INHOUD PUNTE IN MINUTE GENERIES 1 Meervoudigekeuse-vrae 6 10 2 Veiligheid 18 10 3 Materiaal 14 10 SPESIFIEK 4 Meervoudigekeuse-vrae 14 14 5 Terminologie (Maatvorms) 32 25 6 Gereedskap en Toerusting 31 25 7 Kragte 40 40 8 Hegtingsmetodes (Inspeksie van Sweislasse) 18 26 9 Hegtingsmetodes (Spanning en Vervorming) 27 20 TOTAAL 200 180 Blaai asseblief om

MECHANICAL TECHNOLOGY: WELDING 3 AND METALWORK GR12 0625 QUESTION 1: MULTIPLE-CHOICE QUESTIONS (GENERIC) Various options are provided as possible answers to the following questions. Choose the answer and write only the letter (A – D) next to the question numbers (1.1 to 1.6) in the ANSWER BOOK, e.g. 1.7 E. 1.1 Which Act ensures that workers are not dismissed from their jobs if they are infected with HIV/AIDS? A Employment Relations Act B Employment Equity Act C Employment Conditions Act D Employment Health and Safety Act (1) 1.2 A die is used for cutting or forming external threads on round bars and … A square tubing. B angle irons. C plates. D round tubing. (1) 1.3 The legal responsibility of an employer with regard to first aid includes: A Making employees pay for replacing damaged or lost personal protective equipment B Providing a first aid kit C Taking out additional insurance for dangerous work D Ensuring that only one member of staff works on a dangerous job (1) 1.4 Which machine is used to conduct a spark test on carbon steel? A Drilling machine B Lathe machine C Bench grinder D Milling machine (1) 1.5 Which heat treatment process causes extreme hardness of steel? A Annealing B Tempering C Normalising D Hardening (1) 1.6 What is the purpose of annealing steel? A To cool it down B To temper it C To soften it D To harden it (1) [6] Please turn over

MEGANIESE TEGNOLOGIE: SWEIS- EN 3 METAALWERK GR12 0625 VRAAG 1: MEERVOUDIGEKEUSE-VRAE (GENERIES) Verskeie opsies word as moontlike antwoorde op die volgende vrae verskaf. Kies die korrekte antwoord en skryf slegs die letter (A – D) langs die vraagnommer (1.1 tot 1.6) in die ANTWOORDBOEK neer, bv. 1.7 E. 1.1 Watter Wet verseker dat werkers nie uit hulle werk ontslaan word as hulle met MIV/VIGS besmet is nie? A Wet op Arbeidsverhoudinge B Wet op Gelyke Indiensneming C Wet op Diensvoorwaardes D Wet op Beroepsgesondheid en Veiligheid (1) 1.2 'n Snymoer word gebruik vir die sny of vorm van eksterne drade op ronde stawe en ... A vierkantige pype. B hoekysters. C plate. D ronde pype. (1) 1.3 Die wetlike verantwoordelikheid van 'n werkgewer ten opsigte van noodhulp sluit in: A Om werknemers te laat betaal vir die vervanging van beskadigde of verlore persoonlike beskermings toerusting B Voorsiening van ʼn noodhulpkissie C Om addisionele versekering vir gevaarlike werk uit te neem D Om te verseker dat slegs een personeellid gevaarlike take verrig (1) 1.4 Watter masjien word gebruik om 'n vonktoets op koolstofstaal uit te voer? A Boormasjien B Draaibank C Bankslypmasjien D Freesmasjien (1) 1.5 Watter hittebehandelingsproses veroorsaak uiterste hardheid van staal? A Uitgloeiing B Tempering C Normalisering D Verharding (1) 1.6 Wat is die doel van die uitgloeiing van staal? A Om dit af te koel B Om dit te temper C Om dit sag te maak D Om dit te verhard (1) [6] Blaai asseblief om

MECHANICAL TECHNOLOGY: WELDING 4 AND METALWORK GR12 0625 QUESTION 2: SAFETY (GENERIC) 2.1 First aid is the first basic treatment administered to help an injured person, and it usually occurs in three stages. Name the THREE stages. (3) 2.2 Give TWO reasons why the pressure gauge of a hydraulic press must be tested regularly. (2) 2.3 Why is it important to wear safety boots when working in the welding workshop? (1) 2.4 State any TWO safety measures you need to follow BEFORE working with an angle grinder. (2) 2.5 State ONE safety precaution that should be adhered to AFTER working with a power saw. (1) 2.6 State any THREE safety precautions to be followed when handling gas welding cylinders. (3) 2.7 Name any TWO safety precautions that should be considered when drilling a small piece with a pedestal drill. (2) 2.8 State ONE responsibility of the employer regarding safety in the workplace. (1) 2.9 A certain type of workshop layout is shown in FIGURE 2.9 below. Answer the questions that follow. Inspection Product 1 Machine Machine Machine and A B C dispatch Inspection Product 2 Machine Machine Machine and D E F dispatch FIGURE 2.9 2.9.1 Name the type of layout in FIGURE 2.9 above. (1) 2.9.2 State TWO disadvantages of this layout. (2) [18] Please turn over

MEGANIESE TEGNOLOGIE: SWEIS- EN 4 METAALWERK GR12 0625 VRAAG 2: VEILIGHEID (GENERIES) 2.1 Noodhulp is die eerste basiese behandeling wat toegepas word om 'n beseerde persoon te help, en dit vind gewoonlik in drie fases plaas. Noem die DRIE stadiums. (3) 2.2 Gee TWEE redes waarom die drukmeter van 'n hidrouliese pers gereeld getoets moet word. (2) 2.3 Hoekom is dit belangrik om veiligheidstewels te dra wanneer jy in die sweiswerkswinkel werk? (1) 2.4 Noem enige TWEE veiligheidsmaatreëls wat jy moet volg VOORDAT jy met 'n hoekslyper werk. (2) 2.5 Noem EEN veiligheidsmaatreël wat nagekom moet word NADAT jy met 'n kragsaag gewerk het. (1) 2.6 Noem enige DRIE veiligheidsmaatreëls om na te kom wanneer gassweissilinders hanteer word. (3) 2.7 Noem enige TWEE veiligheidsmaatreëls wat in ag geneem moet word wanneer 'n klein stukkie met 'n staanboor geboor word. (2) 2.8 Noem EEN verantwoordelikheid van die werkgewer ten opsigte van veiligheid in die werksplek. (1) 2.9 'n Sekere tipe werkswinkeluitleg word in FIGUUR 2.9 hieronder getoon. Beantwoord die vrae wat volg. Inspeksie Produk 1 Masjien Masjien Masjien en A B C versending Inspeksie Produk 2 Masjien Masjien Masjien en D E F versending FIGUUR 2.9 2.9.1 Noem die tipe uitleg in FIGUUR 2.9 hierbo. (1) 2.9.2 Noem TWEE nadele van hierdie uitleg. (2) [18] Blaai asseblief om

MECHANICAL TECHNOLOGY: WELDING 5 AND METALWORK GR12 0625 QUESTION 3: MATERIALS (GENERIC) 3.1 Explain how you will conduct the following tests to identify various metals: 3.1.1 Machining test (2) 3.1.2 Sound test (2) 3.2 What property of metals can be determined by performing a bend test? (1) 3.3 Name the THREE factors which need to be taken into consideration when heat treatment of steel is done. (3) 3.4 Give the reason why the following heat-treatment processes are performed on steel: 3.4.1 Case hardening (2) 3.4.2 Normalising (2) 3.5 State TWO quenching mediums used for the rapid cooling of steel. (2) [14] Please turn over

MEGANIESE TEGNOLOGIE: SWEIS- EN 5 METAALWERK GR12 0625 VRAAG 3: MATERIAAL (GENERIES) 3.1 Verduidelik hoe jy die volgende toetse sal uitvoer om verskeie metale te identifiseer: 3.1.1 Masjieneringstoets (2) 3.1.2 Klanktoets (2) 3.2 Watter eienskap van metale kan bepaal word deur 'n buigtoets uit te voer? (1) 3.3 Noem die DRIE faktore wat in ag geneem moet word wanneer hittebehandeling van staal gedoen word. (3) 3.4 Gee die rede waarom die volgende hittebehandelingsprosesse op staal uitgevoer word: 3.4.1 Dopverharding (2) 3.4.2 Normalisering (2) 3.5 Noem TWEE blusmediums wat gebruik word vir die vinnige afkoeling van staal. (2) [14] Blaai asseblief om

MECHANICAL TECHNOLOGY: WELDING 6 AND METALWORK GR12 0625 QUESTION 4: MULTIPLE-CHOICE QUESTIONS (SPECIFIC) Various options are provided as possible answers to the following questions. Choose the correct answer and write only the letter (A – D) next to the question numbers (4.1 to 4.14) in the ANSWER BOOK, e.g., 4.15 E. 4.1 For what does the abbreviation SANS stand? A South African National Socials B South African National Standards C South African National Speed D South African National Slag (1) 4.2 Which of the following is an example of a template maker’s machine tool? A Hand saw B Plane C Circular saw D Steel tape (1) 4.3 Welding symbols are used to communicate the requirements of a welding project to the engineers. Identify the welding symbol shown in FIGURE 4.3 below. FIGURE 4.3 A Edge weld B U-butt weld on both sides C Fillet weld on both sides D J-butt weld on both sides (1) 4.4 What is the purpose of a guillotine machine? A To cut steel profiles B To cut sheet metal C To join steel D To bend a plate (1) 4.5 Which of the following tools is used to cut internal threads? A Circular split die B Oval die C Taper tap D All of the above (1) Please turn over

MEGANIESE TEGNOLOGIE: SWEIS- EN 6 METAALWERK GR12 0625 VRAAG 4: MEERVOUDIGE-KEUSE VRAE (SPESIFIEK) Verskeie opsies word as moontlike antwoorde op die volgende vrae verskaf. Kies die korrekte antwoord en skryf slegs die letter (A – D) langs die vraagnommers (4.1 tot 4.14) in die ANTWOORDBOEK neer, bv. 4.15 E. 4.1 Waarvoor staan die afkorting SANS? A Suid-Afrikaanse Nasionale Sosiale B Suid-Afrikaanse Nasionale Standaarde C Suid-Afrikaanse Nasionale Spoed D Suid-Afrikaanse Nasionale Slak (1) 4.2 Watter van die volgende is 'n voorbeeld van 'n templaatvervaardiger se masjiengereedskap? A Handsaag B Skaaf C Sirkelsaag D Staalband (1) 4.3 Sweissimbole word gebruik om die vereistes van 'n sweisprojek aan die ingenieurs te kommunikeer. Identifiseer die sweis simbool wat in FIGUUR 4.3 hieronder getoon word. FIGUUR 4.3 A Kantsweislas B U-stuiksweislas aan beide kante C Hoeksweislas aan beide kante D J-stuiksweislas (1) 4.4 Wat is die doel van 'n guillotine-masjien? A Om staalprofiele te sny B Om plaatmetaal te sny C Om staal te verbind D Om 'n plaat te buig (1) 4.5 Watter van die volgende gereedskapsitems word gebruik om interne drade te sny? A Sirkelvormige gesplete snymoer B Ovaalvormige snymoer C Voorsnytap D Al die bogenoemde (1) Blaai asseblief om

MECHANICAL TECHNOLOGY: WELDING 7 AND METALWORK GR12 0625 4.6 The colour of the regulator for the acetylene cylinder is: A Blue B Red C Green D Black (1) 4.7 What does M stand for regarding supplementary welding symbols? A Melting point B Measure C Metal D Machine (1) 4.8 What is the purpose of applying a free-bend test on a welded joint? A To detect internal defects B To determine the hardness of the weld metal C To detect external surface defects D To determine the ductility of the weld metal (1) 4.9 Identify E in the stress-strain diagram in FIGURE 4.9 below. D BC A E Stress Strain FIGURE 4.9 A Yield point B Break stress C Maximum stress D Limit of proportionality (1) 4.10 Which of the following factors prevents slag inclusion during the welding process? A Weld metal thickness B Proper joint cleaning C Type of welding machine D Electrode thickness (1) Please turn over

MEGANIESE TEGNOLOGIE: SWEIS- EN 7 METAALWERK GR12 0625 4.6 Die kleur van die reguleerder vir die asetileensilinder is: A Blou B Rooi C Groen D Swart (1) 4.7 Waarvoor staan M met betrekking tot aanvullende sweissimbole? A Maak vloeibaar B Meet C Metaal D Masjien (1) 4.8 Wat is die doel van die toepassing van 'n vrybuigtoets op 'n sweislas? A Om interne defekte op te spoor B Om die hardheid van die sweismetaal te bepaal C Om eksterne oppervlakdefekte op te spoor D Om die rekbaarheid van die sweismetaal te bepaal (1) 4.9 Identifiseer E in die spanning-vervormingsdiagram in FIGUUR 4.9 hieronder. D BC A E Vervorming Spanning FIGUUR 4.9 A Breekpunt B Breekspanning C Maksimumspanning D Verhoudingsperk (1) 4.10 Watter van die volgende faktore verhoed slakinsluiting tydens die sweisproses? A Sweismetaaldikte B Behoorlike skoonmaak van die las C Tipe sweismasjien D Elektrodedikte (1) Blaai asseblief om

MECHANICAL TECHNOLOGY: WELDING 8 AND METALWORK GR12 0625 4.11 Identify the type of template shown in FIGURE 4.11 below. FIGURE 4.11 A Frame template B Strip template C Web template D Flange template (1) 4.12 Which of the following is a destructive test on welded joints? A Ultrasonic testing B Liquid dye testing C X-ray testing D Bend testing (1) 4.13 Which of the following components is a part of the angle grinder? A Safety Guard B Stand C Tool rest D Grinding wheel dresser (1) 4.14 FIGURE 4.14 below indicates the elements of a welding symbol. What does the dimension 5 indicate? FIGURE 4.14 A Length of the weld B Pitch of the weld C Root gap D Size of the weld (1) [14] Please turn over

MEGANIESE TEGNOLOGIE: SWEIS- EN 8 METAALWERK GR12 0625 4.11 Identifiseer die tipe templaat wat in FIGUUR 4.11 hieronder getoon word. FIGUUR 4.11 A Raamtemplaat B Strooktemplaat C Webtemplaat D Flenstemplaat (1) 4.12 Watter van die volgende is 'n vernietigende toets op sweislasse? A Ultrasoniese toets B Vloeibare kleurstoftoets C X-straaltoets D Buigtoets (1) 4.13 Watter van die volgende komponente is ’n onderdeel van die hoekslyper? A Veiligheidskerm B Voetstuk C Gereedskapsrus D Slypwielbywerker (1) 4.14 FIGUUR 4.14 hieronder dui die elemente van 'n sweissimbool aan. Wat dui die dimensie 5 aan? FIGUUR 4.14 A Lengte van die sweislas B Steek van die sweislas C Wortelgaping D Grootte van die sweislas (1) [14] Blaai asseblief om

MECHANICAL TECHNOLOGY: WELDING 9 AND METALWORK GR12 0625 QUESTION 5: TERMINOLOGY (TEMPLATES) (SPECIFIC) 5.1 Define the following terms: 5.1.1 Template loft (2) 5.1.2 Plate girders (2) 5.2 State THREE advantages of using templates. (3) 5.3 What is the purpose of supplementary welding symbols? (1) 5.4 Welding symbols are used to convey information from the designer to the welder. FIGURE 5.4 below shows a completed welding symbol. Label the elements A – F of the welding symbol. A B C D E F 10 30 – 100 MIG FIGURE 5.4 (6) 5.5 A steel ring with an inside diameter of 660 mm must be fabricated from a 1 230 x 35 mm rectangular steel bar. Answer the questions that follow. 5.5.1 Calculate the mean diameter of the ring. (3) 5.5.2 Calculate the mean circumference of the ring and then round-off the answer to the nearest whole number. (4) 5.5.3 Make a neat sketch of the steel ring indicating the mean diameter, outside diameter and thickness of the material. (3) 5.6 State THREE properties of a good template loft. (3) Please turn over

MEGANIESE TEGNOLOGIE: SWEIS- EN 9 METAALWERK GR12 0625 VRAAG 5: TERMINOLOGIE (MAATVORMS) (SPESIFIEK) 5.1 Definieer die volgende terme: 5.1.1 Templaatgallery (2) 5.1.2 Plaatlêer (2) 5.2 Noem DRIE voordele van die gebruik van template. (3) 5.3 Wat is die doel van aanvullende sweissimbole? (1) 5.4 Sweissimbole word gebruik om inligting van die ontwerper na die sweiser oor te dra. FIGUUR 5.4 hieronder is 'n voltooide sweissimbool. Benoem die elemente A – F van die sweissimbool. A B C D E F 10 30 – 100 MIG FIGUUR 5.4 (6) 5.5 'n Staalring met 'n binnedeursnee van 660 mm moet van 'n reghoekige staalstaaf van 1 230 x 35 mm vervaardig word. Beantwoord die vrae wat volg. 5.5.1 Bereken die gemiddelde deursnee van die ring. (3) 5.5.2 Bereken die gemiddelde omtrek van die ring en rond dan die antwoord tot op die naaste heelgetal af. (4) 5.5.3 Maak 'n netjiese skets van die staalring wat die gemiddelde deursnee, buite deursnee en dikte van die materiaal aandui. (3) 5.6 Noem DRIE eienskappe van 'n goeie templaatgallery. (3) Blaai asseblief om

MECHANICAL TECHNOLOGY: WELDING 10 AND METALWORK GR12 0625 5.7 FIGURE 5.7 below indicates a roof truss. Label parts A – E. B A C E D (5) [32] Please turn over

MEGANIESE TEGNOLOGIE: SWEIS- EN 10 METAALWERK GR12 0625 5.7 FIGUUR 5.7 hieronder dui op 'n dakkap. Benoem dele A – E. B A C E D (5) [32] Blaai asseblief om

MECHANICAL TECHNOLOGY: WELDING 11 AND METALWORK GR12 0625 QUESTION 6: TOOLS AND EQUIPMENT 6.1 FIGURE 6.1 below shows arc welding equipment. Study the diagram and answer the questions that follow. E A B C D FIGURE 6.1 6.1.1 Label parts A – E. (4) 6.1.2 What is the function of part B? (1) 6.2 Explain the operating principles of the following machines: 6.2.1 Arc welding machine (3) 6.2.2 Spot/Resistance welding equipment (4) 6.2.3 Plasma cutter (4) 6.3 For what does the abbreviation MIG stand? (1) 6.4 Name the hand tool that is used to remove slag from an arc-welded joint. (1) 6.5 Give TWO reasons why coolant is used on a horizontal band saw. (2) 6.6 What is the function of the vertical rolling machine? (1) 6.7 Name TWO processes where oxy-acetylene equipment is used. (2) Please turn over

MEGANIESE TEGNOLOGIE: SWEIS- EN 11 METAALWERK GR12 0625 VRAAG 6: GEREEDSKAP EN TOERUSTING 6.1 FIGUUR 6.1 hieronder toon boogsweistoerusting. Bestudeer die diagram en beantwoord die vrae wat volg. E A B C D FIGUUR 6.1 6.1.1 Benoem dele A – E. (5) 6.1.2 Wat is die funksie van deel B? (1) 6.2 Verduidelik die werksbeginsels van die volgende masjiene: 6.2.1 Boogsweismasjien (3) 6.2.2 Punt-/Weerstand sweistoerusting (4) 6.2.3 Plasmasnyer (4) 6.3 Waarvoor staan die afkorting MIG? (1) 6.4 Noem die handgereedskap wat gebruik word om slak uit 'n boogsweislas te verwyder. (1) 6.5 Gee TWEE redes waarom koelmiddel op 'n horisontale bandsaag gebruik word. (2) 6.6 Wat is die funksie van die vertikale rolmasjien? (1) 6.7 Noem TWEE prosesse waar oksiasetileentoerusting gebruik word. (2) Blaai asseblief om

MECHANICAL TECHNOLOGY: WELDING 12 AND METALWORK GR12 0625 6.8 FIGURE 6.8 below shows a component of gas welding equipment. Study the diagram and answer the questions that follow. A B D C FIGURE 6.8 6.8.1 Identify the component shown in FIGURE 6.8. (1) 6.8.2 Label parts A – D. (4) 6.9 What is the colour code of an oxygen gas cylinder? (1) 6.10 What is the purpose of the flashback arresters on gas welding equipment? (2) [31] Please turn over

MEGANIESE TEGNOLOGIE: SWEIS- EN 12 METAALWERK GR12 0625 6.8 FIGUUR 6.8 toon 'n komponent van gassweistoerusting. Bestudeer die diagram en beantwoord die vrae wat volg. A B D C FIGUUR 6.8 6.8.1 Identifiseer die komponent wat in FIGUUR 6.8 getoon word. (1) 6.8.2 Benoem dele A – D. (4) 6.9 Wat is die kleurkode van 'n suurstofgassilinder? (1) 6.10 Wat is die doel van die terugflitsweerders op gassweistoerusting? (2) [31] Blaai asseblief om

MECHANICAL TECHNOLOGY: WELDING 13 AND METALWORK GR12 0625 QUESTION 7: FORCES 7.1 Graphically determine the magnitude and type of member in the framework shown in FIGURE 7.1 below. Members: AE, BF, CF, DE and EF. SCALE: Space diagram: 1 : 100 Force diagram: 1 mm = 5 N 300 N 100 N B A F E C 45° D 7 000 N 100 N 300 N (19) FIGURE 7.1 7.2 FIGURE 7.2 below shows a 9 m long beam, which is subjected to 3 vertical forces. A force of 4 kN is 2 m from point A. A force of 2 kN is 7 m from point A. A force of 2 kN is 8 m from point A. 4 kN 2 kN 2 kN 2m 5m 1m 1m A B C D E LR RR FIGURE 7.2 7.2.1 Calculate the reactions at LR and RR. Suppose that the moments at A and E are calculated as 0 N. (6) 7.2.2 Calculate the bending moments (BM) at points B, C and D on the beam. Suppose that the shear forces at A and E are to be calculated 0 kN.m. (5) 7.2.3 Draw to scale, the bending moment diagram for the beam. SCALE: 1 cm = 1 kN.m 1 m = 10 mm (4) Please turn over

MEGANIESE TEGNOLOGIE: SWEIS- EN 13 METAALWERK GR12 0625 VRAAG 7: KRAGTE 7.1 Bepaal grafies die grootte en tipe deel in die raamwerk wat in FIGUUR 7.1 hieronder getoon word. Lede: AE, BF, CF, DE en EF. SKAAL: Ruimtediagram: 1: 100 Kragdiagram: 1 mm = 5 N 300 N 100 N B A F E C 45° D 7 000 N 100 N 300 N (19) FIGUUR 7.1 7.2 FIGUUR 7.2 hieronder toon 'n balk van 9 m lank, wat aan 3 vertikale kragte onderwerp word. 'n Krag van 4 kN is 2 m vanaf punt A. 'n Krag van 2 kN is 7 m vanaf punt A. 'n Krag van 2 kN is 8 m vanaf punt A. 4 kN 2 kN 2 kN 2m 5m 1m 1m A B C D E LR RR FIGUUR 7.2 7.2.1 Bereken die reaksies by LR en RR. Gestel die momente by A en E word as 0 N bereken. (6) 7.2.2 Bereken die buigmomente (BM) by punte B, C en D op die balk. Gestel die skuifkragte by A en E word bereken as 0 kN.m. (5) 7.2.3 Teken die buigmomentdiagram vir die balk volgens skaal. Skaal: 1 cm = 1 kN.m 1 m = 10 mm (4) Blaai asseblief om

MECHANICAL TECHNOLOGY: WELDING 14 AND METALWORK GR12 0625 7.3 The original length of a 10 mm round bar is 6 m. It extends by 0,6 mm when a 150 kN tensile load is applied to it. Answer the questions that follow. 7.3.1 Calculate the stress in the round bar. (3) 7.3.2 Calculate the strain in the round bar (answer in full decimals). (3) [40] Please turn over

MEGANIESE TEGNOLOGIE: SWEIS- EN 14 METAALWERK GR12 0625 7.3 Die oorspronklike lengte van 'n ronde staaf van 10 mm is 6 m. Dit verleng met 0,6 mm wanneer 'n treklas van 150 kN daarop toegepas word. Beantwoord die vrae wat volg. 7.3.1 Bereken die spanning in die ronde staaf. (3) 7.3.2 Bereken die vervorming in die ronde staaf (antwoord in volle desimale). (3) [40] Blaai asseblief om

MECHANICAL TECHNOLOGY: WELDING 15 AND METALWORK GR12 0625 QUESTION 8: JOINING METHODS (INSPECTION OF WELD) (SPECIFIC) 8.1 State ONE precaution to eliminate the following welding defects: 8.1.1 Slag inclusion (1) 8.1.2 Centre-line cracks (1) 8.2 A free bend test is performed on a weld. Answer the questions that follow. 8.2.1 Why is this type of test done on a weld? (1) 8.2.2 Explain step-by-step, how the test is done. (4) 8.3 Name THREE types of flames used with the oxy-acetylene welding torch. (3) 8.4 Describe the steps to be followed when performing a nick-break test on a welded joint. (4) 8.5 State TWO preventative measures for the following welding defects during arc welding: 8.5.1 Porosity (2) 8.5.2 Incomplete penetration (2) [18] Please turn over

MEGANIESE TEGNOLOGIE: SWEIS- EN 15 METAALWERK GR12 0625 VRAAG 8: HEGTINGSMETODES (INSPEKSIE VAN SWEIS) (SPESIFIEK) 8.1 Noem EEN voorsorgmaatreël om die volgende sweisdefekte uit te skakel: 8.1.1 Slakinsluiting (1) 8.1.2 Middellynkrake (1) 8.2 'n Vrybuigtoets word op 'n sweislas uitgevoer. Beantwoord die vrae wat volg. 8.2.1 Hoekom word hierdie tipe toets op 'n sweislas gedoen? (1) 8.2.2 Verduidelik stap vir stap hoe die toets gedoen word. (4) 8.3 Noem DRIE soorte vlamme wat saam met die oksiasetileen sweisspuitstuk gebruik word. (3) 8.4 Beskryf die stappe wat gevolg moet word wanneer 'n kerfbreektoets op 'n sweislas uitgevoer word. (4) 8.5 Noem TWEE voorkomende maatreëls vir die volgende sweisdefekte tydens boogsweiswerk: 8.5.1 Poreusheid (2) 8.5.2 Onvolledige penetrasie (2) [18] Blaai asseblief om

MECHANICAL TECHNOLOGY: WELDING 16 AND METALWORK GR12 0625 QUESTION 9: JOINING METHODS (STRESSES AND DISTORTION) (SPECIFIC) 9.1 What is distortion on a welded joint? (2) 9.2 FIGURE 9.2 below shows a T-joint made of a 6 × 30 mm flat bar. The figure shows that shrinkage was present on metal A and deformation occurred at weld B. Answer the questions that follow. 95° B A FIGURE 9.2 9.2.1 State what influence the type of electrode had on causing the distortion in A. (3) 9.2.2 Name THREE factors that may have contributed to residual stress at weld B. (3) 9.2.3 Name FOUR methods to reduce distortion in the joint. (4) 9.3 Describe the effect of cold working on steel. (4) 9.4 Discuss what happens when austenite is allowed to cool slowly? (3) 9.5 What THREE factors control the rate at which metal cools down? (3) 9.6 Name FIVE quenching media used to cool down steel. (5) [27] TOTAL: 200 END

MEGANIESE TEGNOLOGIE: SWEIS- EN 16 METAALWERK GR12 0625 VRAAG 9: VERBINDINGSMETODES (SPANNING EN VERVORMING) (SPESIFIEK) 9.1 Wat is vervorming op 'n sweislas? (2) 9.2 FIGUUR 9.2 hieronder toon 'n T-las gemaak van ʼn 6 × 30 mm plat staaf. Die figuur toon dat krimping op metaal A teenwoordig was en vervorming by sweislas B plaasgevind het. Beantwoord die vrae wat volg. 95° B A FIGUUR 9.2 9.2.1 Noem watter invloed die tipe elektrode gehad het op die vervorming in A. (3) 9.2.2 Noem DRIE faktore wat moontlik bygedra het tot oorblywende stres by sweislas B. (3) 9.2.3 Noem VIER metodes om vervorming in die las te verminder. (4) 9.3 Beskryf die effek van koue bewerking op staal. (4) 9.4 Bespreek wat gebeur as austeniet toegelaat word om stadig af te koel? (3) 9.5 Watter DRIE faktore beheer die tempo waarteen metaal afkoel? (3) 9.6 Noem VYF blusmedia wat gebruik word om staal af te koel. (5) [27] TOTAAL: 200 EINDE

MECHANICAL TECHNOLOGY: WELDING 1 AND METALWORK GR12 0625 FORMULA SHEET FOR MECHANICAL TECHNOLOGY: WELDING AND METALWORK 1. STRESS AND STRAIN πd 2 1.1 Ashaft  4 π(D 2  d 2 ) 1.2 A pipe  4 Maximum stress/Break stress 1.3 Safety factor = Safety working stress Force F 1.4 Stress  OR (σ  ) Area A Change in length (ΔΔL 1.5 Strain ( ε )  Original length (L) Stress σ 1.6 Young' s mod ulus ( E )  OR ( ) Strain ε 2. PYTHAGORAS' THEOREM AND TRIGONOMETRY r y θ x y 2.1 Sin   r x 2.2 Cos   r y 2.3 Tan   x 2.4 r2 = x2 + y2 OR a2  b2  c2

MEGANIESE TEGNOLOGIE: SWEIS- EN 1 METAALWERK GR12 0625 FORMULEBLAD VIR MEGANIESE TEGNOLOGIE: SWEIS- EN METAALWERK 1. SPANNING EN VORMVERANDERING πd 2 1.1 A as  4 π(D 2  d 2 ) 1.2 A pyp  4 Maksimum spanning/Breekspanning 1.3 Veiligheidsfaktor = Veilige werkspanning Krag F 1.4 Spanning  OF (σ  ) Area A Verandering in lengte (ΔΔL 1.5 Vervorming ( ε )  Oorspronklike lengte (L) Spanning σ 1.6 Young se mod ulus (E)  OF ( ) Vervorming ε 2. PYTHAGORAS SE STELLING EN TRIGONOMETRIE r y θ x y 2.1 Sin   r x 2.2 Cos   r y 2.3 Tan   x 2.4 r2 = x2 + y2 OF a2  b2  c2

MECHANICAL TECHNOLOGY: WELDING 2 AND METALWORK GR12 0625 3. TEMPLATES AND DEVELOPMENTS 3.1 Mean Ø = Outside Ø – Plate thickness OR Mean Ø = Inside Ø + Plate thickness 3.2 Mean circumference = π × Mean Ø (where Ø = diameter) 4. SCREW THREADS Drill size = Outside Ø – Pitch

MEGANIESE TEGNOLOGIE: SWEIS- EN 2 METAALWERK GR12 0625 3. MAATVORMS EN ONTWIKKELINGS 3.1 Gemiddelde Ø = Buite Ø – Plaatdikte OF Gemiddelde Ø = Binne Ø + Plaatdikte 3.2 Gemiddelde omtrek = π × Gemiddelde Ø (waar Ø = diameter) 4. SKROEFDRADE Boorgrootte = Buite Ø – Invalshoek