ISO 4778:2019 pdf download

ISO 4778:2019 pdf download.Round steel short link chains for lifting purposes — Chain slings of welded construction — Grade 8
1 Scope
This document specifies the requirements, methods of rating and testing of single, double, three and four leg welded chain slings of grade 8 using components such as sling chains according to ISO 3076 together with links according to ISO 16798, hooks according to ISO 7597 and forged components according to ISO 8539. NOTE 1 For special lifting purposes not covered by this document, additionally intermediate links can be used, for example to connect components to each other having different working load limit. The range of nominal diameter, d n , covered by this document is from 4 mm to 45 mm. Chain slings according to this document are for use in the temperature range –40 °C to +400 °C according to ISO 3056. NOTE 2 Concerning the use and maintenance of chain slings of grade 8, see ISO 3056. Chain slings according to this document comply with the general conditions of acceptance of ISO 1834 and are used for symmetrically distributed loads only. NOTE 3 For rating of chain slings with asymmetrically distributed loads, see ISO 3056. This document does not apply to mechanically joined chain slings. NOTE 4 For mechanically joined chain slings, see ISO 7593.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 3076, Round steel short link chains for general lifting purposes — Medium tolerance sling chains for
chain slings — Grade 8
ISO 7597, Forged steel lifting hooks with latch, grade 8
ISO 8539, Forged steel lifting components for use with Grade 8 chain
ISO 16798, Links of Grade 8 for use with slings
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
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4.4.1 General
Chain slings according to this document shall comply with the mechanical requirements given in Table 2, 3 and 4 for the appropriate test sections. If the whole chain sling is heat treated, it shall be tested as an assembly by subjecting each test section to a value for the manufacturing proof force (MPF) at least equal to the value specified in Tables 2, 3 and 4, calculated on the bases given in Annex A. Subsequently, the chain sling shall be examined by a competent person. The manufacturer shall also verify that all components remain in accordance with the appropriate requirements of the component standards. If only the inserted links are heat treated, they shall be considered as a test section, as well as any parts of the chain sling affected by this heat treatment. These sections shall then be subjected to a value for the manufacturing proof force (MPF) at least equal to the value specified in Tables 2, 3 and 4, calculated on the bases given in Annex A. Subsequently, the inserted links and any parts of the chain slings affected by heat treatment shall be examined by a competent person. The manufacturer shall also verify that all components remain in accordance with the appropriate requirements of the component standards.