NBN ISO 4779:2021

This document specifies the requirements for forged eye hooks with point and latch of grade 4 from
stainless steel and solution annealed for use preferably as a component in chain slings of welded
construction of grade 4 from stainless steel and solution annealed.
IMPORTANT — For other applications, e.g. steel wire rope slings or textile slings, it is important
that the hook design is checked to ensure its fitness for a safe use.
NOTE 1 The grade for the hook according to this document is taken from the grade of the sling chain according
to ISO 1835. Both (sling chains and hooks) have identical scopes and values for the working load limit, WLL,
according to Table 2 and values for the mechanical requirements according to Table 3. Thus, the direct correlation
of hooks to the sling chain is given by the WLL and especially the code system on the product body itself. The
grade of the hook does not define any values of the tensile strength of the hook material. For further information,
see Annex B.
The range of the nominal diameter, dn, of the associated sling chain according to ISO 1835 is from 4 mm
to 22 mm.
Hooks according to this document are for use in the temperature range –100 °C to +400 °C.
These hooks are solution annealed in the finished condition and can therefore be used without
restrictions with regard to the corrosion resistance of the steels according to 5.1.
NOTE 2 The term “eye hook with point and latch” is taken from ISO 1837:2003, Figure 5.