Fabrication and Installation - Offshore Structures: Design, Construction and Maintenance - page 310

In addition, the tolerances for the straightness of tubular members and
beams when assembled into the structure are:

Between the ends of the node stubs, braces should be straight to within
0.12% of the length

●

Between the ends of the node chords, braces should be straight to within
0.10% of the length.

●

The tolerances for the location of cans with different wall thicknesses within
tubular members are as shown in Figure 5.8 and as detailed below:

For joint cans, within 25 mm (1 inch) of the construction drawings.

●

For other changes of wall thickness, within 50 mm (2 inches) of the con-
struction drawings.

●

Figure 5.9 illustrates the tolerances for the mismatch at circumferential
welds and longitudinal seams in tubular members.

● For double-sided welds, the smaller of 10% of the thicker tubular or 6 mm
( 4 inch)
● For single-sided welds, the smaller of 10% of the thicker tubular or 3 mm
( 8 inch)
Where these tolerances are exceeded, the transitions should be made by weld
profiling to a maximum slope of 1:4.

4

1

T m

t

t

Single-sided welds

4

1 D m

t

t

4

Double-sided welds

FIGURE 5.9 Joint mismatch tolerances.