BS ISO 5894:2018 pdf download.Ships and marine technology — Manholes with bolted covers
1 Scope
This document specifies requirements for watertight and oiltight manholes of the current types with bolted covers, for general shipboard use other than for pressure vessels.
It specifies the dimensions for the holes in the plating and the number, size and position of the fasteners.
It is applicable to manholes of raised coaming, surface mounted or recessed cover types.
The details of the manholes are at the discretion of the manufacturer.
2 Normative references
The following documents are referenced in this text in such a way that some or all of their content constitutes requirements of this document. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 262, ISO general purpose metric screw threads — Selected sizes for screws, bolts and nuts
3 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http://www.electropedia.org/
— ISO Online browsing platform: available at http://www.iso.org/obp
4 Typical forms, nominal sizes and dimensions
All dimensions are given in millimetres. Manholes shall be classified as type AO, AE, BO, BE, CO or DO according to nominal sizes (see Figures 1 to 4 and Table 1 to 6). The dimensions of the manholes and the spacing of the fasteners shall be in accordance with Figures 1 to 11 and Tables 1 to 7. The nominal size l 1 × b 1 shall correspond to the length and breadth of the clear opening, as given in Tables 1 to 6. The thread of fasteners (nuts and bolts) shall be in accordance with ISO 262. The thickness of the cover plate, ring and coaming shall be chosen by the user in accordance with the values specified in Table 1 to Table 6 Classification society rules and regulatory conventions can require higher values. Figures 1 to 4 show manhole with raised coaming, surface mounted and recessed cover. In order to ensure interchangeability of covers and gaskets, the dimensions of these components and the fastener coordinates shall be as given in this document.
7 Material
The cover plate, ring and/or coaming, bolts and nuts shall be of marine approved material. The minimal yield strength shall be 235 N/mm 2 . Bolts and nuts shall be of a metal with appropriate mechanical properties, meeting the requirements of relevant standards. Bolts and nuts of equivalent corrosion-resistant metal are permitted. The gasket material shall be suitable for service in contact with oil, sea water and fresh water. The gasket material shall be free from asbestos.
8 Quality of manufacture
The steel plate and sections shall be flat and free from pitting, reasonably clean and sufficiently smooth for a satisfactory joint to be made without recourse to machining the surface. The gasket material shall have a thickness appropriate to the intended service. The dimensional accuracy of the manhole cover, and of the gasket and of the drilling and spacing of the holes for fasteners shall be such as to ensure interchangeability of these components (see also Table 7). The access openings shall be free from rough edges or surfaces likely to cause injury to the hands.