API 653 Chap 12 - Examination / Testing

Question 1

What is Annex G

Answer 1

guidance on MFL

Question 2

What kind of NDE to perform on cavities resulting from gouging or grinding operation to when remove attachment welds of existing reinforcing paltes?

Answer 2

MT or LP

Question 3

Type of NDE for completed welds?

Answer 3

MT or LP

Question 4

What additional exam for unknown toughness having a t > 1/2”?

Answer 4

Fluorescent MT and/or UT

Question 5

NDE for completed welds of stress relieved?

Answer 5

MT or LP after stress relieve BEFore hydro

Question 6

NDE for complete repair butt / fillet welds?

Answer 6

Butt Weld - full length by RT or UT

Question 7

NDE - Removal of attachments?(exclude shell to bottom welds)

Answer 7

Visual

Question 8

NDE - new permanent attachments? (exclude shell to bottom welds)

Answer 8

MT or LP

Question 9

NDE - new welds attaching existing shell plate to new or existing? and if t>1”?

Answer 9

RT, root/final pass full length by MT or LP

Question 10

NDE for NEW shell to bottom joint welds? (3)

Answer 10

1. Full length by using a right angle vacuum box and a solution film
2. applying light diesel oil
3. tested by pressurizing the volume with 15 PSIG (air) and applying a solution film to inside and outside welds.

Question 11

NDE for existing weld shell to bottom joint ?

Answer 11

visual + MT or LP, for full length under a Weld on patch plate. An additional 6” of each side of the weld shall be examined.

Question 12

NDE - critical zone welding , bottom repair welding

Answer 12

root/final pass full length by MT or LP

Question 13

NDE for shell plate repairs, by weld deposit, lap welded patches?

Answer 13

visual + MT or LP

Question 14

NDE for floating roof ? (2)

Answer 14

1. VT from top and bottom

2. air leak, vacuum box, penetrating oil, tracer gas, (annex f)

Question 15

How many RT is need for vertical joints?

1. for new replacement shell to new shell plates
2. new replacement to existing
3. repair joints in existing?

Answer 15

1. 0
2. 1 additional
3. 1 additional

Question 16

How many RT is need for horizontal joints?

1. for new replacement shell to new shell plates
2. new replacement to existing
3. repair joints in existing?

Answer 16

1. 0
2. 1 for each 50 ft additonal
3. 1 for each 50 ft addtional

Question 17

How many RT is need for vertical/horizontal joints?

1. for new replacement shell to new shell plates
2. new replacement to existing
3. repair joints in existing?

Answer 17

1. 0
2. each intersection
3. all repair section

Question 18

What does RT additional mean?

Answer 18

In addition required by API 650 for new construction

Question 19

What does API650 new construction states for RT for vertical? for «3/8”

Answer 19

1. butt weld joints &laquo_space;3/8”, one spot first 10 feet of completed vertical joint, thereafter 100ft , 25% at intersection + spot RT

Question 20

What does API650 new construction states for RT for horizontal?

Answer 20

butt weld joints &laquo_space;3/8”, one spot first 10 feet of completed vertical joint, thereafter 200ft.

Question 21

What does API650 new construction states for RT for vertical? for&raquo_space;3/8” but &laquo_space;1”

Answer 21

following «3/8” + spot RT at the bottom course + spot RT at intersections + «3/8” requirements

Question 22

What does API650 new construction states for RT for vertical? for&raquo_space; 1”

Answer 22

full length RT + everything in&raquo_space;3/8 but «1”

Question 23

RT record of all repair welds shall be marked with?

Answer 23

“R”

Question 24

RT requirement for circular replacement plates?

Answer 24

1 RT regardless of thickness, t >1” weld full length RT

Question 25

shell plate and door sheet welds RT requirement?

Answer 25

all junction need to be RT, 100% if defects are found

Question 26

square and rectangle RT requirement?

Answer 26

at least 1 RT in vertical joint, horizontal, corner

Question 27

min diagnostic length of RT?

Answer 27

6"

Question 28

full hydro test held for how many hours?

Answer 28

24 hours

Question 29

When should hydro be performed?

Answer 29

1. any reconstructed tank 2. major repairs/alteration 3. severity of service increase

Question 30

When do you not need a hydro ? (5)

Answer 30

If engineer + owner signs off , AND 1. new material meet section 4 API650 requirement 2. no impact test needed 3. not exceed 7000 PSI 4. full penetration butt weld 5. RT root/final pass weld

Question 31

shell to bottom weld repair requirements (2)

Answer 31

1. weld can be removed and replace as long as it meet 650 5.1.5.7 2. weld on one side of shell can be completely removed not exceeding 12".

Question 32

tank settlement survery?(5)

Answer 32

1. should be uniformly distributed, around circumference 2. N=D/10, 3. rounded to the EVEN number 4. min is 8 points, 5. max spacing is 32feet