Dimensions

Question 1

Linings - Typical anchor profile of steel required for install of a tank bottom lining.

Answer 1

1.5-4.0 mils

Question 2

Welds - Max undercut of a vert weld & nozzle weld

Answer 2

1/64”

Question 3

Welds - Max undercut of a horizontal weld

Answer 3

1/32”

Question 4

Max diameter of a surface porosity cluster

Answer 4

3/32”

Question 5

Weld Qual - Max allowed discontinuity in a bend test

Answer 5

1/8”

Question 6

Nameplates - Min. size of nameplate letters

Answer 6

5/32”

Question 7

Bottoms - Min external projection of bottom plate on an existing tank. (from toe of shell to bottom FW)

Answer 7

3/8”

Question 8

Reconstruction - Max amount of peaking allowed in vert welds

Answer 8

1/2”

Question 9

Shell Calcs - When calculating tmin for shell LTA, min distance away from a weld where “E” is always 1.0

Answer 9

> 1” or 2t

Question 10

Shell Patch - Minimum overlap of shell lap-patch used to cover a hole (edge of hole to edge of patch)

Answer 10

1”

Question 11

NDE - When performing a MT or PT exam, min distance to clean beyond inspection area.

Answer 11

1”

Question 12

Reconstruction - Max amount of banding allowed in horizontal welds

Answer 12

1”

Question 13

Bottoms - Min overlap required for single-welded lap joints

Answer 13

1”

Question 14

Bottoms - Min external projection of bottom plate on a new tank

Answer 14

2”

Question 15

Vac Box - Min overlap of previously tested areas

Answer 15

2”

Question 16

Bottom Patch - Min overlap of bottom lap-patch used to cover corroded area (edge of corrosion to edge of patch)

Answer 16

2”

Question 17

Bottom Patch - Min distance bottom lap-patch fillet weld to the nearest existing bottom weld

Answer 17

2”

Question 18

Shell Patch - Min radius of a shell lap-patch

Answer 18

2”

Question 19

Reconstruction - If reusing bottom plates, min distance to cut from existing bottom welds (if plates are not deseamed)

Answer 19

2”

Question 20

Reconstruction - If reusing roof plates, min distance to cut from existing roof welds (if plates are not deseamed)

Answer 20

2”

Question 21

Shell Pitting - Max allowed vert length of pits on shell

Answer 21

2” in 8” line

Question 22

Bottom Pitting - Max allowed length of pits in crit zone that can be repaired by weld buildup

Answer 22

2” in 8” arc

Question 23

Bottoms - Radial length of crit zone measured from shell

Answer 23

3”

Question 24

Bottoms - Suggested sand pad thickness

Answer 24

3-4”

Question 25

Welds - Min distance between clusters of surface porosity

Answer 25

4"

Question 26

Shell Patch - Min dimension of a shell lap-patch

Answer 26

4"

Question 27

Shell Patch - Min radius of a shell flush-patch

Answer 27

6"

Question 28

Shell Calcs - When calculating tmin for shell LTA, min distance away from a rivet where "E" is always 1.0

Answer 28

6"

Question 29

Bottom Patch - Min size of a bottom lap-patch that does NOT cross a bottom seam

Answer 29

6"

Question 30

Bottom Patch - Min distance between a bottom lap-patch and the shell for patches that do NOT extend to the shell

Answer 30

6"

Question 31

Reconstruction - If reusing shell plates, min distance to cut from existing shell welds (if plates are not deseamed)

Answer 31

6"

Question 32

RT - Min length of a RT for a vert or hori. weld

Answer 32

6"

Question 33

Weld Qual - Min weld length when qualifying a welder with RT/UT using a coupon or 1st production weld

Answer 33

6"

Question 34

Weld Qual - Min weld length when qualifying a welding operator with RT/UT of a test coupon

Answer 34

6"

Question 35

Shell Patch - Min distance to overlap a shell weld when using a lap-patch

Answer 35

6"

Question 36

Corrosion - Area to dig when checking for soil to air corrosion

Answer 36

6-12"

Question 37

NDE - Distance of eye to part to count as a visual exam

Answer 37

6-24"

Question 38

Vac Box - Typical size of a vac box

Answer 38

6x30"

Question 39

Shell Patch - Min dimension of a shell flush-patch

Answer 39

12"

Question 40

Bottoms - Min dimension that a 3-lap joint can be from other 3-laps, the shell or annular plate joints

Answer 40

12"

Question 41

Bottom Patch - Min dimension of bottom lap-patch that crosses a bottom seam

Answer 41

12"

Question 42

Foundations - Suggested height above grade for new tank bottoms

Answer 42

12"

Question 43

Shell Patch - When adding a shell flush-patch that extends to a horizontal shell weld, min distance to cut the horizontal weld past the new vertical welds

Answer 43

12"

Question 44

Shell Patch - Dimension of a shell flush-patch that is considered either a major repair or alteration

Answer 44

>12"

Question 45

Definition - Dimension of a shell vert weld if repaired or replaced is considered a major repair or alteration

Answer 45

>12"

Question 46

Bottom Patch - Max width of bottom patch in the crit zone

Answer 46

24"

Question 47

Bottoms - Min radial width of annular plate (distance between shell and nearest bottom fillet weld)

Answer 47

24"

Question 48

NDE - Max distance of eye to part to count as visual exam

Answer 48

24"

Question 49

Hot Tap - Min height of liquid above new nozzle during the hot tap operation

Answer 49

36"

Question 50

Weld Qual - Min weld length when qualifying a welding operator with RT/UT of first production weld

Answer 50

36"

Question 51

NDE - Length of sweep board used when checking for banding or peaking

Answer 51

36"

Question 52

Welds - Max distance between welder ID stamps on a tank weld

Answer 52

36"

Question 53

Shell Patch - Max size of a shell lap-patch (vert & hori)

Answer 53

48" x 72"

Question 54

Settlement - Max distance between tank settlement survey points across the inside of the tank

Answer 54

10'

Question 55

Roofs - Max shunt spacing on floating roof

Answer 55

10'

Question 56

CP - Typical tank size for Galvanic CP systems

Answer 56

<20'

Question 57

Shell Calcs - Tank diameter when Variable Point Design method should always be used to calc shell min thickness

Answer 57

>200'

Question 58

Shell - Min offset between vert welds in adjacent courses

Answer 58

5t

Question 59

Bottoms - Min size of bottom welds

Answer 59

Full Fillet