ISO 5117:2023

Overview

ISO 5117:2023 - Automatic steam traps - Production and performance characteristic tests - defines test requirements and methods for automatic steam traps used to remove or recover condensate in steam systems. The standard covers both production (shell) tests and performance characteristic tests to verify steam trap integrity, functionality and operating characteristics for applications such as refineries, power generation and other steam heat-transfer systems.

Key topics and technical requirements

• Test classification
  • Production tests: Shell integrity checks performed on each unit to confirm pressure-retaining capability.
  • Performance characteristic tests: Type or sample testing to evaluate operational behavior and capacities.
• Shell testing (production)
  • Hydraulic shell test at 1.5 × maximum allowable pressure (at 20 °C).
  • For DN ≤ 50, pressure range up to PN 40 or Class 300, a gas test may be used at 6 bar (0.6 MPa) gauge with appropriate safety measures.
  • Minimum test durations specified by nominal size (e.g., DN ≤ 50: 15 s; 65–200: 60 s; ≥250: 180 s).
  • Visible leakage through pressure-retaining walls is unacceptable.
• Performance characteristic tests
  • Operational check: Verify correct open/close cycling under steam and condensate.
  • Minimum and maximum operating pressure (including PMO): Determine pressure limits for correct operation.
  • Maximum operating back pressure (PMOB): Measure allowable outlet pressure that still permits correct functioning.
  • Air venting capability: Verify ability to discharge air at minimum and maximum pressures.
  • Operating temperature (TO) and subcooling: Determine temperatures at which device passes specified capacity.
  • Condensate capacity (QH/QC): Flow testing across the operating pressure range.
  • Live steam loss: Quantify steam leakage through the trap.
  • Annex A & B provide normative test methods for discharge capacity and steam loss determination.

Practical applications and users

ISO 5117:2023 is used to:

• Ensure product conformity, safety and durability of steam traps during manufacture (quality control) and as type testing.
• Compare different trap designs and brands for selection, lifecycle cost and energy-efficiency decisions.
• Reduce live steam loss and improve plant energy utilization in steam systems. Key users:
• Valve and steam trap manufacturers and test laboratories.
• Plant engineers, reliability and maintenance teams in power plants, refineries, chemical plants and steam-using industries.
• Procurement and specifications teams requiring objective test-based acceptance criteria.

Related standards and notes

• Normative reference: ISO 6553 (Automatic steam traps - Marking).
• See ISO 6704 for labyrinth/orifice steam traps (different test applicability).
• ISO 5117:2023 consolidates and updates earlier standards (ISO 6948, ISO 7841, ISO 7842).

Keywords: ISO 5117:2023, automatic steam traps, steam trap testing, production tests, performance tests, condensate capacity, live steam loss, shell testing, operating pressure, air venting capability, energy efficiency, power generation.