Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

api 653 chapter 8 > API 653 Chap 9 > Flashcards

API 653 Chap 9 Flashcards

1
Q

All repair work must be authorized by?

A

AI OR Engineer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Alteration must be approved by?

A

Engineer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Can AI approved alteration?

A

No, only limited or routine repair (anything work that WILL NOT require hydro)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is Annex F of API653? and can it be used alone?

A

NDE requirement summary, and no, must use other section 1-12

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What should replacement shell plate be accordance with?

A

as-built standard

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What should the thickness be of the replacement shell?

A

shall not be less than the greatest nominal thickness of any plate in the same course adjoining the
replacement plate except where the adjoining plate is a thickened insert plate.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the min dimension of replacement shell plate?

A

Greater ( 12 or 12t)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the min spacing requirements for t

A 
R=6"
B=6"
H=3"
V=6"
A=12"
C= Great (3" or 5t)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Prior to welding the new vertical joints, what needs to be done? (3)

A

(1) .the existing horizontal welds shall be cut for a minimum distance of 12 in. beyond the new vertical joints.
(2) The cut shall extend past or stop short of existing bottom plate welds by at least 3 in. or 5t.
(3) Weld the shell- to-bottom weld last

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the min spacing requirements for t > 0.5”

A 
Greater 
R=6" or 6t
B=10" or 8t
H=10" or 8t
V=10" or 8t
A=12" or 12t
C= (3" or 5t)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What should shell replacement plates be welded with?

A

butt joints with complete penetration / complete fusion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the acceptable lapped patch shell repairs (3)?

A
  1. butt welded
  2. lap welded
  3. riveted tank shells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Could lapped patch repair be considered as permanent repairs?

A

Yes, subject to an ongoing inspection and maintenance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

When can lapped patch shell repairs not be used?

A

When t > 1/2” and not to replace door sheets or shell plates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the requirements of the repair plate for closure of holes? (5)

A
  1. t < 1/2”
  2. 3/16 &laquo_space;tpatch&laquo_space;1/2” or thickness of shell plate adjacent to the repairs
  3. min R = 2” min
  4. overlap of 1” & 8t max
  5. D» 2”
  6. E=.7
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

When can lapped patch repairs be used ? (2)

A
  1. removal of existing shell openings

2. removal of severely corroded areas

17
Q

What is the max vertical/horizontal dimension of a repair plate? and min?

A

48” x 72” , 4”

18
Q

When can lapped patch repair not be used on? (4)

A
  1. lap welded shell seams
  2. riveted shell seams
  3. lapped patch repair plates.
  4. distorted areas
19
Q

What are the requirements of the repair plate for severely corroded area (5)

A
  1. t < 1/2”
  2. 1/8&raquo_space; tpatch&laquo_space;1/3 ts
  3. overlap of 1” & 8t max
  4. E=.35
  5. no less than 3/16” and no more than 1/2”
20
Q

With lapped welded joints repair plate when is the E used for?

A

To determine the hydrostatic pressure load.

21
Q

What are repair methods? (4)

A
  1. grind with smooth contour
  2. localized depositions
  3. replacement plates
  4. lap welded patch plates
22
Q

when is it not necessary to remove existing weld reinforcement?

A

when existing tank with satisfactory service history

23
Q

New Penetrations larger than NPS 4 shall be installed with the use of an insert plate or thickened insert plate, in what scenario? (2)

A

(1) shell plate thickness is greater than 1/2 in.

(2) the shell plate material does not meet the current design metal temperature criteria.

24
Q

The existing reinforcing plate may be removed and a new reinforcing plate added except that reinforcement plate replacement is not permitted on
existing stress relieved assemblies. What is not known?

A

If it is not known whether the assembly was thermally stressed relieved, then the alteration shall meet the
requirements of API 650, Section 5.7.4.

25
Q

When the upper half of the existing reinforcing

plate meets all requirements of API 650, what can happen?

A

it can be left in place with approval of the purchaser.

26
Q

what min thickness should be under the the new a telltale hole,

A

1/2 tmin .

27
Q

The new reinforcing plate shall be in accordance with Figure 9.3. What about if to maintain weld spacing?

A

If required to maintain weld spacing, a tombstone shaped reinforcing plate may be used

28
Q

A new bottom may be installed through what?

A

an existing tombstone reinforcing plate,

29
Q

What is min dimension for a repair for a tank bottom?

A

is 12 inches

30
Q

When can the min dimension for a repair plate be less than 12 inches? (5)

A
  1. When the diameter > 6”
  2. does not overlap a seam
  3. does not overlap a bottom seam
  4. not placed fully or partially over an existing patch
  5. extender beyond the corroded area by 2”
31
Q

repairs within the critical zone requirements?

A
  1. max plate thickness = 1/4” and must meet toughness
    req.
  2. when the repair plate is within 6” of the shell, must be tombstone shaped.
  3. perimeter welds should minimum 2 pass
  4. cannot be butt welded to existing patch
    5.
32
Q

Are you allow to weld overlays in the critical zone?

A

No, except for scattered pits, pinholes, cracks, shel lto bottom weld, welded on patches

33
Q

When is welded on patch plates not permitted in the critical zone?

A

when operating temp exceed 200F for CS and 100F for SS.

34
Q

What is min thickness of new roof plates?

A

3/16”

35
Q

How to minimize evaporation loss in floating roof primary seals?

A

no more than 1/4” of roof seal system should be out an in service tank at one time.

36
Q

Hot tap with unknown toughness limitations? (4)

A
  1. max 4 NPS
  2. shell plate temperature shall be at or above min shell design temp for the entire hot tapping operation
  3. All nozzles shall be reinforced
  4. shell stress is less than 7KSI
37
Q

Hot tap requirements? (3)

A
  1. welding with low hydrogen electrodes
  2. min height of tank liquid above hot tap location is 3 feet
  3. reinforcement plate to be pneumatically tested
38
Q

Where is hot tap not allowed? (2)

A
  1. not permitted on roof with gas/vapor
  2. not on severely pitting shell
  3. where it will cause SCC or caustic cracking
39
Q

What is min spacing for hot tap?

A

square root of RT
R=radius of tank shell
T=shell plate thickness

api 653 chapter 8 (36 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions