Overview
ISO 6454:1984 defines the principal dimensions, types and construction requirements for strum boxes (crépines d’aspiration) fitted to the ends of bilge suction pipes on seagoing and inland navigation vessels. The standard’s purpose is to prevent obstruction of bilge suction piping by solid matter while promoting maintainability and safe installation. It explicitly excludes use of these strum boxes for bilge suction piping in machinery spaces and shaft tunnels.
Key Topics
- Scope: Applies to deep-sea ships and inland navigation ships. Users must also observe applicable legal and class regulations for each ship type.
- Types: Four types are specified by shape and perforation pattern:
- R2: Cylindrical with perforated cylindrical side and non-perforated top.
- R3: Cylindrical with perforated side and perforated top.
- S2: Square with perforated sides and non-perforated top.
- S3: Square with perforated sides and perforated top.
- Designation: Example format is shown in the standard, e.g. Crépine ISO 6454 R3-300 (type R3, nominal diameter DN 300).
- Dimensional basis: Dimensions are given relative to nominal pipe diameter (DN); installation clearances (gap between pipe and strum box top) must not exceed 3 mm and certain dimensions (such as plate height h) are adjusted at installation.
- Perforated plate requirements:
- Each hole area is approximately 79 mm² as a reference.
- The ratio of total hole passage area to pipe cross-section (De²) must be > 2 for R2/S2 and > 3 for R3/S3.
- The open area fraction of the perforated plate must be ≥ 0.30.
- Materials & finish:
- Minimum carbon steel thickness is 3 mm.
- After fabrication, strum boxes must be hot-dip galvanized or protected by an equivalent corrosion-resistant coating agreed with the purchaser. For hot-dip galvanizing, zinc deposition must be ≥ 600 g/m² per face.
- Manufacture & maintainability: Strum boxes should be designed for easy dismantling for inspection and cleaning.
Applications
- Installed at the terminal of bilge suction pipes to prevent ingress of solids and debris.
- Improve bilge system reliability, reduce clogging risk and simplify routine maintenance and cleaning.
- Not suitable for bilge suctions inside machinery spaces or shaft tunnels; alternative arrangements and regulations apply there.
Related Standards
- ISO 1461: Hot-dip galvanized coatings on finished iron and steel products (specification).
- ISO 4200: Steel tubes - general tables for dimensions and linear masses.
- Developed by ISO/TC 8 (Shipbuilding and marine structures).
For specification or procurement, refer directly to the ISO 6454:1984 text for exact dimensions, tables and figures and ensure compatibility with class and statutory requirements.