ISO 4064-4:2024

Overview

ISO 4064-4:2024 - "Water meters for cold potable water and hot water - Part 4: Non‑metrological requirements not covered in ISO 4064‑1" defines the non‑metrological technical requirements for water meters used on fully charged, closed conduits. It covers meters that record integrated volume (mechanical, electrical/electronic, and hybrid designs), as well as optional electronic ancillary devices. The standard specifies mechanical interfaces, pressure and temperature capability, dimensional requirements, and pressure‑loss considerations to ensure safe, compatible and installable water‑meter equipment.

Key technical topics and requirements

• Scope of application
  • Cold potable water meters (maximum admissible temperature, MAT = 30 °C).
  • Hot water meters (MAT up to 180 °C depending on class).
  • Maximum admissible pressure (MAP) ≥ 1 MPa (10 bar); reduced MAP of 0.6 MPa for pipe nominal diameters DN ≥ 500 mm.
• Mechanical connections and dimensions
  • Threaded connections conforming to ISO 228‑1 (dimensions and tolerances).
  • Flanged connections in accordance with ISO 7005‑2/3 for appropriate pressures.
  • Defined overall meter sizes and envelope dimensions; fixed or adjustable overall lengths for combination meters.
• Concentric, cartridge and exchangeable metrological modules
  • Cylindrical envelope dimensions and manifold interface designs for concentric and cartridge meters.
  • Standardized dimensions for exchangeable metrological modules (horizontal/vertical/combination flow patterns) to support interchangeability.
  • Informative annexes provide manifold layouts, cartridge connection solutions and examples of adaptors/converters.
• Pressure‑loss and installation considerations
  • Pressure‑loss requirements and minimum clearances behind flanges to permit installation/removal.
• Ancillary devices
  • Electronic ancillary devices are covered; normally optional but may be required by national/international regulation.

Practical applications - who uses this standard

• Meter manufacturers - design and dimension meters, exchangeable modules, cartridge/concentric forms and manifold interfaces to ensure compatibility and regulatory compliance.
• Utilities and water companies - specify procurement requirements for meters that meet MAP/MAT and installation constraints.
• Engineering consultants and system designers - integrate meters into pipework, account for pressure‑loss and flange/thread interfaces.
• Installers and maintenance teams - follow dimensional and clearance guidance for safe installation and replacement of modules.
• Test houses and conformity assessors - evaluate non‑metrological characteristics and installation suitability in conjunction with ISO 4064‑1 metrological tests.
• Regulators and procurement bodies - reference the standard for technical tender specifications and safety limits.

Related standards (normative references)

• ISO 4064‑1 | OIML R 49‑1 - Metrological and technical requirements (metrology).
• ISO 228‑1 - Pipe threads where pressure‑tight joints are not made on the threads.
• ISO 7005‑2 / ISO 7005‑3 - Metallic flanges (cast iron, copper alloy/composite).

Keywords: ISO 4064‑4:2024, water meters, cold potable water, hot water, non‑metrological requirements, meter dimensions, MAP, MAT, threaded connection, flanged connection, concentric meters, cartridge meters, exchangeable modules.