CASTING & FORGING

Question 1

WHAT IS THE DEFINITION OF CASTING?

Answer 1

CASTING IS A PROCESS OF POURING MOLTEN METAL INTO A PREPARED MOLD AND ALLOWING THE METAL TO SOLIDIFY.

Question 2

WHAT ARE 4 DIFFERENT CASTING METHODS?

Answer 2

1. PERMANENT MOLD CASTING
2. CENTRIFUGAL CASTING
3. INVESTMENT CASTING
4. PRECISION CASTING

Question 3

WHAT CAN A PATTERN BE MADE OF?

Answer 3

• WOOD
• METAL
• PLASTIC
• SAND
  -P.O.P.

Question 4

WHAT IS ANOTHER NAME FOR INVESTMENT CASTING?

Answer 4

LOST WAX CASTING

Question 5

WHAT ARE SOME DISCONTINUTIES THAT CAN BE FOUND IN CAST PARTS?

Answer 5

• HOT TEAR
• HOT CRACK
• LACK OF FUSION

Question 6

WHAT NDT METHOD CAN BE USED FOR HOT TEARS?

Answer 6

RADIOGRAPHY

Question 7

WHAT NDT METHOD CAN BE USED FOR A HOT CRACK?

Answer 7

ULTRASONIC

Question 8

WHAT NDT METHOD CAN BE USED FOR LACK OF FUSION?

Answer 8

LIQUID PENETRANT

Question 9

WHAT IS THE DEFINITION OF FORGING?

Answer 9

THE WORKING OF METAL INTO A USEFUL SHAPE BY HAMMERING OR PRESSING. IT IS ONE OF THE OLDEST METAL FORMING PROCESSES. MOST FORGING OPERATIONS ARE CARRIED OUT HOT, ALTHOUGH SOME METALS ARE COLD FORGED.

Question 10

WHAT MAKES FORGINGS STRONGER THAN CASTINGS?

Answer 10

THE GRAIN FLOW STRUCTURE

Question 11

THE SHAPING OF HOT METAL WITHIN THE CAVITIES OF 2 DIES THAT COME TOGETHER COMPLETELY IS AN EXAMPLE OF WHAT TYPE OF FORGING?

Answer 11

CLOSED DIE FORGING.

Question 12

WHAT IS THE DEFINITON OF ANISOTROPY?

Answer 12

THE STRUCTURAL PROPERTY OF NON-UNIFORMITY IN DIFFERENT DIRECTIONS.

Question 13

WHAT ARE 4 TYPES OF FORGING DEFECTS?

Answer 13

1. LAPS
2. SEAMS
3. HOT TEARS
4. BURSTS

Question 14

WHAT IS THE DEFINITION OF CASTINGS?

Answer 14

COMPONENTS THAT HAVE THEIR SHAPE DUE TO MELTING AND RESOLIDIFYING OF AN ALLOY INTO THE DESIRED SHAPE. PRODUCTS INCLUDE VALVES, AND BEARINGS.

Question 15

WHAT IS THE DEFINITION OF WROUGHT?

Answer 15

COMPONENTS THAT HAVE BEEN SHAPED BY MECHANICAL FORCE. PRODUCTS INCLUDE WIRE, METAL SHEETS, AND TUBE.

Question 16

WHAT IS THE DEFINITION OF POWDER METALLURGY?

Answer 16

COMPONENTS THAT ARE MADE WITH THE USE OF METALLIC POWDER THAT IS MIXED WITH A BINDER AND THEN WHILE UNDER PRESSURE AND HIGH TEMPERATURE ARE PRESSED INTO THE SHAPE THAT IS DESIGNED. PRODUCTS INCLUDE UNIQUE SELF LUBRICATING BEARINGS, AND FILTERS. THIS IS DONE BY IMPREGNANTING PARTS WITH LUBRICANT.

Question 17

WHAT ARE THE TOP AND BOTTOMS PARTS OF A MOLD CALLED?

Answer 17

TOP -> COPE
BOTTOM -> DRAG

Question 18

WHY ARE PATTERNS TYPICALLY MADE LARGER THAN THE PART ITSELF?

Answer 18

TO COMPENSATE FOR THE SHRINKAGE THAT OCCURS AS THE METAL SOLIDIFIES. THE INCREASE IN SIZE IS DEPENDANT ON THE TYPE OF METAL USED.

Question 19

WHAT ARE THE THREE DISTINCT REGIONS OR ZONES IN A MACROSTRUCTURE?

Answer 19

• CHILL ZONE
• COLUMNAR ZONE
• EQUIAXED ZONE

Question 20

WHAT IS CHILLING?

Answer 20

RAPID COOLING

Question 21

WHAT IS INOCULATING (ADDING INSOLUBLE IMPURITIES)?

Answer 21

OXIDES THAT ARE ADDED IN CASTING AND ACT AS NUCLEATION POINTS FOR THE STEEL ATOMS TO ATTACH TO. EX) ALUMINUM OXIDES, TITANIUM OXIDES, SILICON OXIDES.

Question 22

WHY IS GRAIN SIZE IMPORTANT?

Answer 22

BECAUSE IT AFFECTS THE MECHANICAL PROPERTIES OF A METAL OR ALLOY

Question 23

WHAT ARE CASTING DEFECTS?

Answer 23

CASTINGS THAT EXHIBIT A SIZE, SHAPE, ORIENTATION, OR LOCATION THAT MAKES THEM DETRIMENTAL TO THE USEFUL SERVICE LIFE OF THE CASTING.

Question 24

WHAT INSPECTION METHODS ARE USED FOR THE SURFACE OF A CASTING?

Answer 24

• LIQUID PENETRANT
• MAGNETIC PARTICLE

Question 25

WHAT INSPECTION METHODS ATE USED FOR BELOW THE SURFACE OF A CASTING?

Answer 25

- RADIOGRAPHY - ULTRASONIC

Question 26

WHAT INSPECTION METHOD IS USED FOR NON-FERROUS METALS?

Answer 26

LIQUID PENETRANT.

Question 27

WHERE DOES THE IMPROVEMENT OF MECHANICAL PROPERTIES WHEN FORGING COME FROM?

Answer 27

- GENERAL CONSOLIDATION OF METAL AND CLOSING OF GAS AND CONTRACTION CAVITIES BY MEANS OF MECHANICAL PRESSURE - REFINEMENT OF THE CRYSTAL STRUCTURE BY PRODUCING "FLOWLINES" - DESTRUCTION OF THE CONTINUITY OF THE INTERGRANULAR CONCENTRATIONS OF IMPURITIES AND INCLUSIONS.

Question 28

WHAT ARE 2 CATEGORIES OF FORGING?

Answer 28

- OPEN-DIE FORGING - CLOSED-DIE FORGING

Question 29

WHAT IS THE DEFINITION OF OPEN-DIE FORGING?

Answer 29

WHERE THE WORKING SURFAVE OF THE DIES IS FLAT OR OF UNIFORMCURVED CONTOUR AND SHAPING IS DONE BY MANIPULATION USING TOOLS OF SIMPLE SHAPE.

Question 30

WHAT IS THE DEFINITION OF CLOSED-DIE FORGING?

Answer 30

WHERE IMPRESSION DIES ARE USED (DIES WITH A SPECIFIC PRE-DETERMINED SHAPE) AND THE METAL IS SHAPED BY BEING FORCED INTO THE DIE IMPRESSIONS.

Question 31

WHAT IS HOT UPSET FORGING?

Answer 31

IN THIS PROCESS A BAR OF UNIFORM CROSS-SECTION IS GRIPPED BETWEEN GROOVED DIES AND PRESSURE IS APPLIED ON THE END IN THE DIRECTION OF THE AXIS OF THE BAR BY MEANS OF A HEADING TOOL. THE METAL FLOWS UNDER THE APPLIED PRESSURE AND FILLS THE CAVITY BETWEEN THE DIES.

Question 32

WHAT IS THE ROLLING OPERATION?

Answer 32

IT CONSISTS OF PASSING HOT METAL BETWEEN TWO ROLLS THAT THROUGH THE APPLICATION OF PRESSURE, REDUCE THE SIZE OF THE METAL SHAPE.

Question 33

WHAT HAPPENS IN THE EXTRUSION PROCESS?

Answer 33

THE HOT BILLET OF METAL IS PLACED IN A CHAMBER WHERE IT IS SUBJECT TO HIGH PRESSURE OF A HYDRAULICALLY OPERATED RAM. THIS PRESSURE FORCES THE METAL THROUGH A PRE-SHAPED OPENING IN A DIE.

Question 34

WHAT IS THE DRAWING PROCESS?

Answer 34

THE METAL IS PULLED THROUGH A DIE RATHER THAN BEING PUSHED THROUGH LIKE THE EXTRUSION PROCESS.