Underwater Welding

Question 1

TWO TECHNIQUES:

Answer 1

1) SELF CONSUMING

2) MANIPULATIVE

Question 2

HAZARDS:

Answer 2

1) SHOCK
2) FALLING MATERIAL
3) EXPLOSIVE GASES.

Question 3

POWER SUPPLY:

Answer 3

1) DC WELDING GENERATOR
2) 400 AMP OR LARGER
3) 300 APMS MINIMUM
4) 200 MINIMUM IN EMERGANCY

Question 4

DC STRAIGHT POLARITY:

Answer 4

(ELECTRO NEGATIVE)

1) USUAL METHOD USED IN U/W CONSTRUCTION
2) RESULTS IN A LONGER LIFE OF THE ELECTRODE HOLDER

Question 5

DC REVERSE POLARITY

Answer 5

(ELECTRO POSITIVE)

1) USED WHEN MANUFACTURER RECOMMENDS, PARTICULARLY FOR STAINLESS STEEL
2) CONTROL OF WELD BEAD AND SHAPE
3) IMPROVED RUNNING CHARACTERISTICS

Question 6

POWER CABLES:

Answer 6

1) CABLE SELECTION IS BASED ON THE TOTAL LENGTH OF THE CIRCUIT
2) 2/0 CABLE IS USED WHEN CABLE LENGTH IS 400 FT OR LESS FROM THE POWER SOURCE
3) 3/0 CABLE IS USED WHEN CABLE LENGTHS IN EXCESS OF 400 FEET FROM THE POWER SOURCE
4) SIZE 1/0 LAST TEN FEET TO ELECTRODE HOLDER FOR DIVER MANEUVERABILITY

Question 7

SAFETY SWITCHES:

Answer 7

1) A POSITIVE ACTING, INFUSIBLE CURRENT INTERRUPT SWITCH THAT ALLOWS THE SWITCH OPERATOR TO BE PROTECTED FROM ALL CHANCE OF SHOCK AND ARC FLASH.
2) RATED AT 400 APMS.
3) POSITIONED SO IF HANDLE DROPS, IT DOES NOT CLOSE CIRCUT
4) DC 600A RATED CIRCUIT BREAKER IS THE BEST CHOICE.

Question 8

WELDING ENVIRONMENTS:

Answer 8

1) COFFERDAMS
2) MINI-HABITATS
3) WET WELDING

Question 9

WELD STENGTH;

Answer 9

1) SAFETY FACTOR

2) WELD LENGTH - USE 1,000 LBS PER LINEAR INCH.

Question 10

NON DESTRUCTIVE TESTING:

Answer 10

1) ENSURES WELDS ARE FREE OF DETRIMENTAL CONDITIONS
2) CRACKS
3) INCOMPLETE FUSION

Question 11

NDT METHODS:

Answer 11

1) UNDERWATER VISUAL TESTING
2) UNDERWATER MAGNETIC PARTICLE TESTING
3) UNDERWATER ULTRASONIC GAUGING

Question 12

FOR QUALITY ASSURANCE:

Answer 12

UNDERWATER VISUAL TESTING AND UNDERWATER MAGNETIC PARTICLE TESTING.