API-653 -DIMENSIONS
Definitions -Length of shell-to-bottom weld that if
repaired is considered a major repair or alteration
>0" --- ref. (653 : 3.18.g )
Linings -Typically anchor profile of steel surface
required for the installation of a tank bottom lining
1.5 -4.0 mils --- ref. (652:7.5)
Welds -Maximum undercut of a vertical weld & nozzle
weld
1/64" --- ref. (650: B.5.2.b )
Welds -Maximum undercut of a horizontal weld
1/32" --- ref. (650: 8.5.2.b )
Welds -Maximum diameter of a surface porosity
cluster
3/32" --- ref. (650: 8.5.2.c )
Weld Qualification -Max allowed discontinuity in a
Bend Test
1/8" --- ref. (IX: QW-163 )
Nameplates -Minimum size of nameplate letters
5/32" --- ref. (650: 10.1.1 653: 13.1.1 )
Bottoms -Minimum external projection of bottom plate
on an existing tank (from toe of shell-to-bottom FW)
3/8" --- ref. (653: 4.4.5.7 )
Reconstruction -Max amount of peaking allowed in
vert welds
1/2" --- ref. (653: 10.5.4 )
, Shell Calcs -When calculating t minfor shell L TA,
minimum distance away from a weld where "E" is
always 1.0
> 1" or 2t --- ref. (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)
1" --- ref. (653: 9 .3.2.3 )
NDE -When performing a PT examination, minimum
distance to clean beyond the area to be examined
1" --- ref. (V: T-642.b )
NDE -When performing a MT examination, minimum
distance to clean beyond the area to be examined
1" --- ref. (V: T-741.1.b )
Reconstruction -Maximum amount of banding allowed
in a horizontal welds
1" --- ref. (653: 10.5.5 )
Bottoms -Minimum overlap required for Single-welded
lap joints
1" --- ref. (650: 5.1.3.5 )
Bottoms -Minimum external projection of bottom plate
on a new tank
2" --- ref. (650: 5.4.2 )
Vacuum Box -Minimum overlap of previously test
surfaces when using a vacuum box
2" --- ref. (650: 8.6.5 )
Bottom Patch -Minimum overlap of bottom lap-patch
used to cover corroded area (edge of corrosion to
edge of patch)
2" --- ref. (653: Fig. 9.13 )
Bottom Patch -Minimum distance bottom lap-patch
fillet weld to the nearest existing bottom weld
Definitions -Length of shell-to-bottom weld that if
repaired is considered a major repair or alteration
>0" --- ref. (653 : 3.18.g )
Linings -Typically anchor profile of steel surface
required for the installation of a tank bottom lining
1.5 -4.0 mils --- ref. (652:7.5)
Welds -Maximum undercut of a vertical weld & nozzle
weld
1/64" --- ref. (650: B.5.2.b )
Welds -Maximum undercut of a horizontal weld
1/32" --- ref. (650: 8.5.2.b )
Welds -Maximum diameter of a surface porosity
cluster
3/32" --- ref. (650: 8.5.2.c )
Weld Qualification -Max allowed discontinuity in a
Bend Test
1/8" --- ref. (IX: QW-163 )
Nameplates -Minimum size of nameplate letters
5/32" --- ref. (650: 10.1.1 653: 13.1.1 )
Bottoms -Minimum external projection of bottom plate
on an existing tank (from toe of shell-to-bottom FW)
3/8" --- ref. (653: 4.4.5.7 )
Reconstruction -Max amount of peaking allowed in
vert welds
1/2" --- ref. (653: 10.5.4 )
, Shell Calcs -When calculating t minfor shell L TA,
minimum distance away from a weld where "E" is
always 1.0
> 1" or 2t --- ref. (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)
1" --- ref. (653: 9 .3.2.3 )
NDE -When performing a PT examination, minimum
distance to clean beyond the area to be examined
1" --- ref. (V: T-642.b )
NDE -When performing a MT examination, minimum
distance to clean beyond the area to be examined
1" --- ref. (V: T-741.1.b )
Reconstruction -Maximum amount of banding allowed
in a horizontal welds
1" --- ref. (653: 10.5.5 )
Bottoms -Minimum overlap required for Single-welded
lap joints
1" --- ref. (650: 5.1.3.5 )
Bottoms -Minimum external projection of bottom plate
on a new tank
2" --- ref. (650: 5.4.2 )
Vacuum Box -Minimum overlap of previously test
surfaces when using a vacuum box
2" --- ref. (650: 8.6.5 )
Bottom Patch -Minimum overlap of bottom lap-patch
used to cover corroded area (edge of corrosion to
edge of patch)
2" --- ref. (653: Fig. 9.13 )
Bottom Patch -Minimum distance bottom lap-patch
fillet weld to the nearest existing bottom weld
