ISO 5031:1977

Overview

ISO 5031:1977 - "Continuous mechanical handling equipment for loose bulk materials - Couplings and hose components used in pneumatic handling - Safety code" is a safety code that complements the general rules of ISO/T 1819. It defines special safety requirements for couplings and flexible hose components used in the pneumatic handling and transport of loose bulk materials. The requirements apply regardless of the intended use of the equipment and are aimed at ensuring safe design, installation, operation and maintenance.

Key topics and requirements

• Pressure resistance and leak-tightness: Flexible hose assemblies with their couplings must withstand at least 1.5 times the maximum working pressure of the transport system and be leak-tight.
• Anti-disengagement design: Couplings that attach flexible hoses to rigid pipework must not permit a sudden or violent disengagement if loosening begins.
• Static electricity control:
  • Flexible elements must be constructed to permit passage of static electricity to adjacent elements where the transported product or hose material can generate charge.
  • Grounding (earthing) is required when accumulation of electrostatic charge is possible. Short flexible elements may be shunted exceptionally.
• Accessible installation:
  • Connections between flexible and fixed pipework must be at accessible locations and should not require ladders or temporary scaffolding.
  • Work height for making connections should generally not exceed 1.50 m.
  • Where multiple flexible connections exist for different products that must not mix, use different types or diameters to prevent wrong hookups.
• Operation and maintenance:
  • Only authorized operating personnel may connect or disconnect flexible elements.
  • Disconnection during operation is prohibited.
  • Periodic inspections must verify hose condition, seal quality, and correct coupling tightening.
  • Unused flexible hoses must be stored in a designated place to avoid accidental damage.

Applications and who uses this standard

ISO 5031 is intended for:

• Manufacturers and designers of pneumatic conveying systems and continuous mechanical handling equipment for loose bulk materials
• Plant engineers, safety managers and maintenance teams in bulk-handling industries (cement, grain, minerals, powders)
• Installers, commissioning personnel and inspectors responsible for pipework, flexible hoses and couplings
• Procurement and QA teams specifying safe couplings and hose assemblies

Adopting ISO 5031 helps reduce leak risks, prevent hazardous disconnections, minimize electrostatic ignition risks and improve safe access for installation and maintenance.

Related standards

• ISO/T 1819 - General safety code for continuous mechanical handling equipment (complementary rules)
• ISO 5028 - Safety code for pneumatic conveying installations for loose bulk materials

Keywords: ISO 5031, pneumatic handling, couplings, hose components, safety code, flexible hoses, loose bulk materials, static electricity, pressure resistance, installation, inspection.