Section 8.0
Deck Mooring Fittings
8.1 INTRODUCTION
Many nat~ional, shipyard and vendor standards for mooring fittings cxlst. I n almost all cases these
standards lack complete information on the true strength of the fitl.ings. Even wbere back-up cal-
culations are provided, questions still arise. For complete evaluation of existing standards, extensive
stress analysis woul d be required for e·ach filling and component. This has not been I,Jndertaken here.
Instead, existing standards have been reviewed and recommendations made based upon successful
or uosuccessfuJ experience with t hem. In some cases even superficial <Ulalysis is sufficient to expose
deficiencies. Any fitting of undocumented or incomplete strength charac teristics should be verified
for compliance with the recommended strength criteria by detailed calculatjons and prototype testing.
Generally, reference is made to the widely-used International Standards (ISO). British St.andards
(BS) and Japanese Indu.mial St.andards (lIS). A complete' listing of ISO, BS and 1IS standards for
mooring fittings and equipment may be found in Section 4.One dlfficuHy in estabtishing tbe general acceptability of a panjcular fittll1g is the inconsistency in
load and design parameters between various standards. This can be parlially compensated for by the
continuing adopt.ion of ISO Standards as the basis of national or vendor standards (e.g. the BS
and Japanese standards for bollards now incorporate tbe appropriate ISO Standard requjrements).
Unfortunately, tbe ISO Standards do not yet cover all mooring fittings , nor do [hey always provid.e
the detail included in some national standards. Moreover, some ISO and national standards have not
been updated to keep pace with industry progress, adding further to the difficulty in knowing which
strength cr.iteria are relevant to a filling.Reproduction of the relevant ISO and natlonal standards, which would have assisted in understanding
the complexities of load and design criteria for mooring fitiings and improved the effectiveness of
this report, has been precluded. owing to copyright constraints. The individual standards institutions
should be contacted for detailed applications.Tbe following notes itemise some of the crilical elements in selecting and .in. tailing acceptable deck
mooring fittings.8.2 VERTICAL BOLLARDS
ISO 3913 and BS MA 12, ParIs 1 and 2, show standards for bollards with diaJucters from 100 mm
10 800mm. All hough the ISO Standard is recommended for the design of bollards, where detail is
insuffjcient, e.g. in construction and weld details. reference should be made to the British Standard
dealing with these point.s. The bitts should penetrate the baseplate rather than just be welded 10
the top of the baseplate, and strengthening rib plates should be fitted i.n the base. The JIS and other
national standards. which closely follow tbe ISO Standard, arc acceptable provided conSl.rucliOJl
details follow the above principle. The range of sizes covered by other standards may vary, such
as the JlS whicb also includes 355, 450 and 560mm sizes.The tabulated 'single rope maumum loading' quoted in the ISO Standard is the SWL when the rope
is belayed in a figure-of-eight fashion (the ISO sa fety factor is the same as that recommended in
Section 4, Table 4.3). According to the ISO Standard (and some national standards), rwo ropes of
this value may be applied in figure-oF-eight fashion near the base, or alternatively a single rope of
twice the load may be applied, as a loop, at heights up to 1.2 times the bollard nominal diameter.