nasionale senior sertifikaat graad 11 - best...

1

Tyd: 2 Ure Punte 150

Hierdie vraestel bestaan uit 14 bladsye insluitend die voorblad

MEGANIESE TEGNOLOGIE

JUNIE 2015

NASIONALE

SENIOR SERTIFIKAAT

GRAAD 11

Meganiese Tegnologie Graad 11 MDE JUNIE 2015

2

INSTRUKSIES EN INLIGTING

1 Skryf jou NAAM op die antwoordboek.

2 Antwoord AL dievrae in die antwoordboek.

3 Lees AL die vrae sorgvuldig deur.

4 Nommer volgens die nommerstelsel in die vraestel.

5 Skryf netjies en leesbaar.

6 Toon alle berekeninge en eenhede.

7 Kandidate mag nie-programeerbare wetenskaplike sakrekenaars en

teken/wiskunde instrumente gebruik

8 Die waarde van gravitasieversnelling moet as 10 m/s2geneem word.

9 Die laaste bladsy van die vraestel is die formuleblad

10 Handig die vraestel saam met die antwoordboek in

VRAAG INHOUD PUNTE TYD 1 Multi keuse vrae 20 15 minutes 2 Veiligheid 18 20 minutes 3 Gereedskap en Toerustingt 33 20 minutes 4 Materiale 12 10 minutes 5 Terminologie 20 20 minutes 6 Samevoegingsmetodes 18 15 minutes 7 Kragte 21 20 minutes

TOTAAL 150 120 minutes CINCINNATI VERDEELKOP TABEL VIR DIE FREESMASJIEN

Gat sirkels Side 1 24 25 28 30 34 37 38 39 41 42 43 Side 2 46 47 49 51 53 54 57 58 59 62 66

Standaard wisselratte

24 x 2 28 32 40 44 48 56 64 72 86 100

)(40 lingsonderverdegatalnwaarn

formulegsIndekserin


3

VRAAG 1: MEERVOUDIGEKEUSE-VRAE Kies die korrekte antwoord uit die wat gegee word A, B, C en D en skryf jou keuse langs die vraagnommer neer.

1.1 Die beitelrus van die slypwiel moet omtrent… A

B C D

2 mm 5 mm 3 mm 4 mm van die wiel wees

(1) 1.2 Gassilinders,(suurstof en asetileen) moet.. A

B C D

So na as moontlik aan mekaar geberg word Opmekaar gestapel word om spasie te spaar Onder `n afdak geberg word Apart van mekaar in `n koel plek geberg word

(1)

1.3 n Wyserplaatmeter word gebruik om…

A

B C D

Die binnekant van twee parallelle vlakke noukeurig te meet Vas te stel of `n krukas gebuig is Gate wat geboor is se dieptes te meet Te keer dat gietstukke krom trek

(1) 1.4 By die versorging van die senterdraaibank geld die volgende A

B C D

Maak skoon na gebruik en bedek met `n doek oor naweke Wend ghries aan alle werkende dele Dreineer ratkaste om roes te voorkom nadat gewerk is daarmee Hout produkte kan mooi afgewerk word op die senterdraaibank

(1)


4

1.5 Die afkorting MIG staan bekend as… A

B C D

Met in agneming van die metaal wat gesweis word Meet in gram hoe swaar die metaal is Metaal –inerte gas wat gebruik word Metaal – intensiewe graad wat gebruik word

(1) 1.6 Rekbaarheid in `n metaal verwys na… A

B C D

die vermoë om deurdringing te weerstaan die vermoë om skokladings te weerstaan die vermoë om weerstand te bied teen uitwendige kragte die vermoë om van vorm te verander deur in lengte te rek

(1) 1.7 Die tmperatuur waarby staal vir verharding geblus word, staan bekend

as…

A

B C D

Normaliserings temperatuur Verhardingstemperatuur Temperings temperatuur Uitgloeings temperatuur

(1)

1.8 Tapsdraaiwerk is die proses waar… A

B C D

`n spits profiel geskep word wat intern of ekstern in deursnit toeneem of afneem `n spits profiel geskep word wat in diameter verskil `n spits profiel geskep word wat in lengte verander as gevolg van die rekbaarheid van staal `n spits profiel geskep word wat toelaat dat die staal verkort

(1)

1.9 By die vertikale freesmasjien kan die freeskop geswaai word teen `n hoek

van…

A

B C D

35° 40° 45° 55°

(1)


5

.10 Identifiseer die freessnyer in die figuur.

A

B C D

Verspringendetandfrees Syfrees Silindriese freessnyer Enkelhoek frees

(1) 1.11 Identifiseer die sweissimbool van `n reghoekige-stuiklas in die gegewe

figure

A B C D

(1) 1.12 Identifiseer die tipe sweislas wat gevorm is in die figuur

A

B C D

Dubbel skuinslas Reghoekige stuiklas Hoeklas (dubbel) J-stuiklas

(1)

1.13 Sweissoldering is `n adhesieproses waarin metale deur.. A

B C D

Verhitting Smelting Korrosie Dreinering saamgevoeg word

(1)


6

1.14 Wat is die lesing op die mikrometerskaal wat gegee is?

A

B C D

10, 16 mm 12,16 mm 12, 56 mm 12, 66 mm

(1)

1.15 Die eenheid wat vir buigmomente gebruik word is.. A

B C D

Newton - millimeter (Nmm) Meter (m) Newton - meter (Nm) Kilo Newton (KN)

(1)

1.16 Die formule wat gegee word sal gebruik word om…

tapsvanlengte2tapsvandeursnitKleintapsvandeursnitGrootTanθ

u�

A

B C D

Die hoek te bereken waarteen die saamgestelde slee gestel moet word Die lengte te bereken van die as waarteen die saamgestelde slee gestel moet word Die wydte te Bereken van die as waarteen die saamgestelde slee gestel moet word Die hoek te bereken waarteen die verdeelkop gestel moet word

(1)


7

1.17 Identifiseer die tipe freeswerk wat gewys word in die figuur.

A

B C D

Sy en vlak freeswerk Enkelhoek freeswerk Gewone freeswerk Verspringendetand freeswerk

(1)

1.18 Identifiseer die blusmedia wat gebruik word om afkoeling in staal te verkry A

B C D

Gesmelte koper Pekel Suur Natriun bikarbonaat

(1)

1.19 Wat is die waarde van krag X op die balk?

A

B C D

15 kN 60 kN 30 kN 120 kN

(1)

15 kN X kN

4m 2m


8

1.20 `n Wringsleutel word geruik om… A

B C D

Deure oop te sluit Metaal los te wring van mekaar Te keer dat boute en moere los raak Die entspeling op `n krukas te bepaal

(1)

TOTAAL VRAAG 1: [20]

VRAAG 2: VEILIGHEID 2.1 Noem TWEE oorsake van ongelukke in die werksplek. (2) 2.2 Voorsorg by die hantering van gassilinders is baie belangrik.

Noem DRIE voorsorgmaatreëls in verband hiermee.

(3) 2.3 Noem VIER veiligheidsreëls wat jy sal toepas wanneer daar met `n

draaibank of freesmasjien gewerk word.

(4) 2.4 Noem VIER vereistes voordat sweis- of vlamsnywerk gedoen word. (4) 2.5 Beskryf hoe jy nuwe slypwiele sal monteer op die bankslypmasjien. (5)

TOTAAL VRAAG 2: [18] VRAAG 3: GEREEDSKAP EN TOERUSTING 3.1 Wat is die funksie van die binnemikrometer? (2) 3.2 Die volgende lesingwaarde moet voorgestel word met `n skets van die

binnemikrometer.`n Verlengstaaf van 125-150mm moet gebruik word om die lesing voor te stel. Toon alle berekeninge en onderdele duidelik aan. Lesing: 143, 54 mm

(5) 3.3 Noem drie tapse wat algemeen gebruik word vir skroefdraadsnywerk (3) 3.4 Maak netjiese deursnitsketse van die volgende boormetodes; 3.4.1 Boor, versink en teenboor (2) 3.4.2 Boor en versink (2)


9

3.5 Benoem die volgende sketse: 3.5.1 Die universele freesmasjien FIGUUR 1 (8)

FIGUUR 1

3.5.2 Die boogsweismasjien FIGUUR 2 (8)

3.6 Daar is VIER hoofsoorte boogsweismasjiene wat gebruik word in die

industrie. Noem TWEE groepe.

(2)


1

23

451

6

781

1

2

74

85

65

3

4 5

FIGUUR 1

FIGUUR 2


10

VRAAG 4: MATERIALE 4.1 Identifiseer die oond in FIGUUR 3 wat gebruik word by die vervaardiging

van staal.

(2)

4.2 Voltooi die metaaleienskappe tabel (4)

Eienskap Beskrywing Hardheid 4.2.1

4.2.2 Vermoë om kragte en buiging in alle rigtings te absorbeer Smeebaarheid 4.2.3

4.2.4 Vermoë om skokladings te weerstaan 4.3 Verdudelik wat die term hittebehandeling beteken. (2) 4.4 Die hardheid wat verkry word in staal word bepaal deur DRIE faktore. Noem

die DRIE faktore

(3) 4.5 Verduidelik die term uitgloeiing. (2)


FIGUUR 3


11

VRAAG 5: TERMINOLOGIE 5.1 Tapsdraaiwerk op die senterdraaibank kan op verskillende metodes gedoen

word. Noem TWEE van hierdie metodes.

(2) 5.2 `n Bus, met `n interne taps van 180mm moet geboor word. Die grootkant van

die gat is 75mm in deursnit. Die ingeslote hoek is 12° aan die kleinkant. Bereken die deursnit van die kleinkant. (d)

(6)

5.3 Die saamgestelde – slee metode word gebruik om tapse (skuinstes) te sny op

materiaal. Noem hoe die saamgestelde slee-metode toegepas word op die draaibank

(8) 5.4 Wat is die funksie van die verdeelkop by die freesmasjien? (1) 5.5 Benoem die skets van die verdeelkop (1-5) in FIGUUR 4 (5)

5.6 Maak gebruik van die eenvoudige indekserings metode en bepaal die

indeksering vir die volgende:

5.6.1 35 onderverdelings (3) 5.6.2 17 ondrverdelings (3)


Ø 75mm

180 mm

d

FIGUUR 4


12

VRAAG 6: SAMEVOEGINGSMETODES 6.1 Wat beteken die sweissimbool in FIGUUR 5 gemerk 1–4? (4)

6.2 Daar bestaan VYF hoofsoorte sweislasse. Hierdie lasse kan deur middel van

sweissoldering, gassweising of boogsweising gevorm word. Identifiseer die DRIE sweislasse wat hieronder geïllustreer is

6.2.1

(1) 6.2.1

(1) 6.2.3

(1) 6.3 Watter gasbottel gebruik `n linksom skroefdraad? (1)

ARC 10

FIGUUR 5


13

6.4 Verduidelik die gebruik van die toerusting in FIGUUR 6.4.1 en FIGUUR 6.4.2 onderskeidelik

(2)

6.4.1 6.4.2

6.5 Noem enige TWEE faktore wat `n invloed het op`n sweislas.. (2) 6.6 Die onderstaande diagram verwys na `n deursnit van `n smeltsweislas.

Identifiseer die dele hieronder vanaf A–F in FIGUUR 6.

(6)


FIGURE 6


14

VRAAG 7 KRAGTE 7.1. Definieer die volgende basiese begrippe van sisteme van kragte hieronder: 7.1.1 Ewewig (1) 7.1.2 Resultante (1) 7.1.3 Bow se notasie (1) 7.2. `n Massa van 1350kg hang van twee toue wat teen 30° en 45° onderskeidelik

van die horisontaal hang.

7.2.1 Teken die ruimtediagram (2) 7.2.2 Teken die vektor- / kragtediagram (skaal 1mm=100N ) (3) 7.2.3 Bereken die spanning in die toue (5)

7.3. Figuur 7 dui `n balk aan wat aan beide kante deur RL en RR gestut word

3 m 1m 4m 2m

7.3.1 Die groottes van A en B. (6) 7.4. `n Ronde staaf met `n buite diameter van 32mm en `n binne diameter van

28mm is onderworpe aan `n trek las van 12 kN

7.4.1 Bereken die area van die ronde staaf (4) 7.4.2 Bereken die spanning wat veroorsaak word. (3) TOTAAL VRAAG 7 [21] GROOT TOTAAL [150]

RL RR

8N 12N 6N

FIGUUR 7

1

Marks 150 This memorandum consist of 11 pages.

MECHANICAL TECHNOLOGY

MEMO JUNE 2015

NATIONAL

SENIOR CERTIFICATE

GRADE 11

Mechanical Technology Grade 11 MDE JUNE 2015

2

QUESTION 1: MULTIPLE-CHOICE 1.1 C 1.2 D 1.3 B 1.4 A 1.5 C 1.6 D 1.7 B 1.8 A 1.9 C 1.10 B 1.11 D 1.12 C 1.13 A 1.14 D 1.15 C 1.16 A 1.17 C 1.18 B 1.19 1.20 C

TOTAL QUESTION 1: [20]


3

QUESTION 2: SAFETY 2.1 Causes of accidents x Poor housekeeping

x Loose clothing x Improper use of tools x Inaccurate setting-up of machines Any 2 x 1=2

(2) 2.2 Handling and storage of gas cylinders.

x Store full cylinders apart from empty ones. x Keep cylinders in a cool place and protect them from sunlight and

other sources of heat. x Always store and use cylinders in an upright position. x Store oxygen cylinders away from fuel cylinders. x Never stack cylinders on top of each other. x Do not bang or work on cylinders. x Never allow cylinders to fall from any height. ( Cylinders must be

chained to prevent this) x Do not allow oil or grease to come into contact with oxygen fittings as

oxygen and oil form an inflammable mixture. x Keep caps on the cylinders for protection. x The thread on an oxygen cylinder is a right-hand thread. x The thread on the acetylene cylinder is a left-hand thread. Any 5x1=5

(5) 2.3 Safety precautions when working with a lathe or milling machine

x Make sure that all the guards are in place. x Don’t use a machine or come close to its moving parts whilst wearing

loose clothing. x Check that there is no oil or grease on the floor around the machine. x Do not leave spanners or keys on rotary parts x Never apply a wrench to revolving work. x Always clamp workpiece and holding devices safely and firmly. x Do not use your hands to remove cuttings whilst the machine is in

motion. x Never adjust the machines whilst it is in motion. x Resist the habit of leaning on machinery. x Do not attempt to stop a machine with your hands. x Pay attention to cutting fluid control before switching on a machine.

Any 4x1=4

(4)

2.4 Requirements before welding or flame-cutting can be done.

x An operator must be instructed on how to use apparatus safely x A work place must be effectively partitioned off.


4

x An operator must use protective equipment. x Ensure that effective ventilation is provided or mask or hoods to

maintain a supply of safe air for breathing is available. x Electrical leads must be well insulated. x Electrode holder must be well insulated to prevent electric shock. x The welder must be completely insulated by boots, gloves and rubber

mats x Any vessel that contains flammable or poisonous substances must

not be welded or heated unless it has been properly cleaned. Any 4x1=4

(4)

. Mounting a new grinding wheels to a bench grinder

x Select the correct type of wheel for job. x Never use a grinding wheel that is damaged, not properly dressed

and that has cracks. x Make sure that the wheel speed does exceed the manufactures

recommendation. x Never force the wheel onto the spindle. x Use one smooth paper spacer on each side of the wheel. x Use true and correctly recessed flanges of the same size. x Gently tighten the grinding wheel with a spanner only enough to hold

it firmly. x Replace the guards correctly. x Let the machine idle before you dress it with an emery wheel dresser. x Stop the machine and reset the tool rest to 3mm and it must be

parallel to the wheel surface. Any5x1=5

(5)


QUESTION 3: TOOLS AND EQUIPMENT 3.1 Function of the inside micro meter

x To measure an inside diameter or two inside of two parallel surfaces accurately

(2) 3.2 The following reading value must be shown with a sketch of the inside micro

meter. An extension piece 125-150mm must be used to show this reading. Show all calculations as well as the parts clearly. Reading value: 143, 54 mm

(5)


5

3.3 Types of taps used for screw cutting. x Taper taps x Second taps or intermediate taps x Bottoming taps or plug taps.

(3) 3.4 Draw neat cross cut sketches of the following drilling methods; (2) 3.4.1 drill, countersink and counter bore (2) 3.4.2 drill and countersink (2) 3.5 Label the following pictures. 3.5.1 The universal milling machine

1. Adjustable overarm 2. Arbor support 3. Horizontal spindle 4. Table 5. Knee and saddle 6. Handwheel 7. Powerfeed unit 8. Base

(8)

3.5.2 The arc welding machine

1. Electrode holder 2. Welding machine 3. Electrode 4. Earth cable 5. Earth cable 6. Workpiece 7. Arc gap 8. Electrode

(9) 3.6 Four main types of arc welding machines used in industry.

x AC Machines x Inverters x MIG x TIG welding

(4)



6

QUESTION 4: MATERIALS 4.1 Steel is produced through different processes and requires special furnaces.

(See figures) Identify these specific furnaces used.

(2) Open hearth furnace 4.2 Properties of materials 4.2.1 Ability to resist penetration, scratching, abrasion, indentation and

wear (1)

4.2.2 Elasticity (1) 4.2.3 Ability to reshaped in all directions without cracking (1) 4.2.4 Toughness (1) 4.3 Heat treatment is heating and cooling of metals in their solid state so as to

change their properties. (3)

4.4 x Workpiece size

x Quenching rate x Carbon content

(3) 4.5 To relieve internal stresses which may have been set up during previous

workings of the metal, to soften them in order to facilitate the machining processes, make them ductile, refine their grain structures and reduce brittleness

(3)

TOTAL QUESTION 4: [12] QUESTION 5: TERMINOLOGY 5.1 x The tailstock can be set over for longer external tapers

x Taper turning attachment can be used for external tapers and for boring short internal tapers

x A straight-edged turning tool can be used for very short tapers x The compound slide rest can be swiveled around for turning external

tapers or short internal tapers x Use a tracer or computer numeral controlled lathe. Any2x1=2

(2)


7

5.2 Calculation of small diameter 5.2.1

mmdd

dd

dTan

xLdDTan

16.3784.377584.37

7584.37751051.03601802

756

20

� �� u

u�

� T

(6)

5.3 Cutting procedure using compound slide 5.3.1 x Release the lock nut of the compound slide

x Swing the compound slide to half the included angle x Tighten the lock nut doesn’t over tight tool it. x Mount the cutting tool holder in the tool post, the cutting tool

must be set centre height. x Use the compound slide feed handles and feed the cutting

tool slowly into the work piece. x Proceed to the end of cutting length, return to starting

position, and feed the cutting tool in for the next cut. x Repeat the procedure until the taper is completed. x On completion, test the taper with a taper ring gauge for size

and correct angle

(8) 5.4 Function and uses of a dividing head The dividing head breaks up the circumference of circular workpiece into a

number of equal divisions, and also used for indexing, gears, flute and spline cutting.

(3) 5.5 Components of a dividing head 1. Worm gear

2. Plunger for locking index plate 3. Index plate 4. Crank handle 5. Single stary worm

(5)


8

5.6 Simple indexing 5.6.1

cycleholeaonholestoturnfulltoequalisturnsofnumberThe

NturnsofNumber

42614261

4261

66

711

55

3551

3540

40

u y

(3) 5.6.2

cycleholeaonholeaonturnsfulltoequalisturnsofnumberThe

NturnsofNumber

3412234122

34122

22

1762

1740

40

u

(3)

TOTAL QUESTION 5: [30] QUESTION 6: JOINING METHODS 6.1 Welding symbols 1. Arc welded

2. Convex 3. Flame 4. 2mm root gap

(4)

6.2 Welding joints. 6.2.1 T-Fillet joint (1) 6.2.2 Edge joint (1) 6.2.3 Single bevel joint (1)


9

6.3 Left-handed cylinder Acetylene (1) 6.4 The uses of soldering equipments 6.4.1 Used for soldering electronic components (1) 6.4.2 Used for soldering copper plumbing pipes. (1) 6.5 Four factors which influence welding joint. x Type of material

x Number of welds x Type of welding rod x Size of weld x Presence of oxygen/hydrogen x Preparation Any 4x1=4

(4) 6.6 Fusion welded joint. A Slag

B Gas envelope C Coating D Weld metal E Molten pool F Parent metal

(6)


QUESTION 7 FORCES 7.1. Basic concepts of systems of forces: 7.1.1 Equilibrium- When two forces or more forces act on a body and the

body remains at rest.

(2) 7.1.2 Resultant- If a system of forces acts on a body and a single force

can be found that has the same effect as the system

(2) 7.1.3 Bow`s notation-Is a method which can be used to simplify problem

solving where three or more forces are applied to a body in a system of forces.

(2)


10

7.2. A mass of 1350 kg is supported by two ropes which are inclined at 30° and 45°

respectively to the horizontal.

7.2.1 Draw the space diagram

(2)

7.2.2 Draw the vector/ force diagram (scale 1mm = 100N

(3)

7.2.3 Determine the tension in both the ropes (5) 7.3. The figure shows a beam supported by RL and RR.

3 m 1m 4m 2m

7.3.1 Calculate the magnitudes of supports RL and RR. (6)

RL RR

8N 12N 6N

1350x10 N

30°


11

7.3.1 ��

��

NRL

RL

mNmNmNRL

NRR

RR

mNmNmNRR

1410567212

786122610

1210

484824864123810

?

¨©§ �� ?

u�u�u u?

?

�� ?

u�u�u u

(6) 7.4. A round tube with the outside diameter 32mm and inside diameter of 28mm. is

subjected to a tensile load of 12 kN

7.4.1 Area of the round bar 7.4.1

��

� �

2

22

22

5.18842832

4

m

dDA

�

�

S

S

(4)

7.4.2 Stress 7.4.2

2

3

/66.635.1881012

mN

AFStress

u

(4)

TOTAL [25]

nasionale senior sertifikaat graad 11 - best...

Documents