API 653 Data Sheets-Dimensions

Linings- Typically anchor profile of steel surface required for the installation of a tank bottom lining   652:  7.5

Welds- Maximum undercut of a vertical weld & nozzle weld   650:  8.5.2.b

Welds- Maximum undercut of a horizontal weld

Welds- Maximum diameter of a surface porosity cluster   650:  8.5.2.c

Weld Qualification- Max allowed discontinuity in a bend test  IX:  QW-163

Nameplates- Minimum size of name plate letters   650:  10.1.1 &  653:  13.1.1.1

Bottoms- Minimum external projection of bottom plate on an existing tank (from toe of shell-to-bottom FW)  653:  4.4.5.7

Reconstruction- Max amount of peaking allowed in vertical welds  653:  10.5.4

Shell Calcs- When calculating t_min for shell LTA, minimum distance away from a weld where "E" is always 1.0   653:  4.3.3.1 (definitions)

Shell Patch- Minimum overlap of shell lap-patch used to cover a hole (edge of hole to edge of patch)   653:  9.3.2.3

NDE- When performing a PT examination, minimum distance to clean beyond the area to be examined     V: T-642.b

NDE- When performing a MT examination, minimum distance to clean beyond the area to be examined   V:  T-741.1.b

Reconstruction- Maximum amount of banding allowed in a horizontal weld   653:  10.5.5

Bottoms- Minimum overlap required for single-welded lap joints   650:  5.1.3.5

Bottoms- Minimum external projection of bottom plate on a new tank   650:  5.4.2

Vacuum Box- Minimum overlap of previously test surfaces when using a vacuum box

Bottom Patch- Minimum overlap of bottom lap-patch fillet weld to the nearest existing bottom weld   653:  Fig. 9.13

Bottom Patch- Minimum distance bottom lap-patch fillet weld to the nearest existing bottom weld   653:  Fig. 9.13

Shell Patch- Minimum radius of a shell lap-patch   653:  9.3.1.4

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

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

Shell Pitting- Maximum allowed vertical length of pits on a tank shell   653:  4.3.2.2.b

Bottom Pitting- Maximum allowed length of pits in the critical zone that can be repaired by weld-buildup   653:  9.10.1.6.a

Bottoms- Radial length of critical zone measured from shell   653:  3.10

Bottoms- Suggested sand pad thickness

Welds- Minimum distance between clusters of surface porosity  650:  8.5.2.c

Shell Patch- Minimum dimension of a shell lap-patch    653:  9.3.1.7

Shell Patch- Minimum radius of a shell flush-patch   653:  Fig. 9.1 "R" dimension

Shell Calcs- When calculating t_min for shell LTA, minimum distance away from the rivet where "E" is always 1.0  653:  4.3.4.1

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

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

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

RT- Minimum diagnostic length of a RT for vertical or horizontal welds  

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

Weld Qualify-Minimum weld length when qualifying a welding operator with RT/UT of a test coupon  IX:  QW-302.2

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

Corrosion- Area to dig when checking for soil-to-air corrosion   575:  8.2.10

NDE- Distance of eye-to-part to count as visual exam   577:  9.3.1.e

Vacuum Box- Typical size of a vacuum box

Shell Patch- Minimum dimension of a shell flush-patch    653:  9.2.2.1

Bottoms- Minimum dimension that a 3-lap joint can be from: other 3-laps, the shell, or annular plate joints  650:  5.1.5.4.2

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

Foundations- Suggested height above grade for new tank bottoms  650:  B.3.1

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

Shell Patch- Dimension of a shell flush-patch that is considered either a major repair or alteration  653:  3.20.c

Definition- Dimension of a shell vertical weld if repaired or replaced is considered a major repair of major alteration  653:  3.20.e

Bottom Patch- Maximum width of bottom patch in the critical zone

Bottoms- Minimum radial width of annular plate (distance between shell and nearest bottom fillet weld)  650:  5.1.5.4.3 & 5.5.2

NDE- Maximum distance of eye-to-part to count as visual exam  575:  9.2.1

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

Weld Qualify- minimum weld length when qualifying a welding operator with RT/UT of first production weld  IX:  QW-305.1

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

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

Shell Patch- Maximum size of shell lap-patch (vertical & horizontal dimensions)

Settlement- Maximum distance between tank settlement survey points across the inside of the tank  653:  Fig. B.2

Roofs- Maximum shunt spacing on floating roof

CP- Typical tank size for Galvanic CP systems

Settlement- Maximum distance between tank settlement survey points around the outside diameter of the tank  653:  Fig. B.1/12.5.2

NDE- Maximum distance between RT's in horizontal welds when welding to existing shell plates  653:  12.2.1.2.b & c

Shell Calcs- Tank diameter when Variable Point Design method should always be used to calc shell minimum thickness  653:  4.3.3.4

Shell- Minimum offset between vertical welds in adjacent courses  650:  5.1.5.2.b

Bottoms- Minimum size of bottom welds