Overview
ISO 10522:2021 - Agricultural irrigation equipment - Direct-acting pressure-regulating valves - defines construction, performance requirements and test methods for direct-acting pressure-regulating valves intended for irrigation systems. It covers valves for water (≤ 60 °C) that may contain common fertilizers and chemicals, and applies to nominal sizes up to and including DN 100 (4 in). The standard updates the 1993 edition, extending size range, harmonizing test temperatures and refining test and marking requirements.
Key topics and technical requirements
- Scope and definitions: clear terminology for pressure regulators (single-range, multi-range, adjustable, integral, regulated pressure, reference velocity, etc.).
- Classification: by regulation assembly (single-/multi-range, adjustable), construction (ordinary vs integral), zero-flow behavior, and accuracy levels (Class A ±10%, Class B ±20%).
- Construction & marking: body, adjustment assembly, connections, adjustable stop and required durable markings (manufacturer/trademark, nominal size, nominal pressure, flow direction arrow).
- Mechanical and functional tests: detailed test methods including regulation curve, regulation uniformity, tightness, regulated pressure at zero flow, pressure loss, and response to inlet pressure changes.
- Strength & durability: resistance to internal hydrostatic pressure (metal and plastics bodies), on/off cycle testing and changing-condition cycles to assess longevity.
- Performance parameters: declared pre-set pressure (referenced using a reference velocity), minimum flow rate, initial regulation pressure, and allowable deviations.
- Test conditions: testing water temperature range and face-to-face tolerances for plastics bodies have been updated in this edition.
Applications
ISO 10522:2021 is used to:
- Specify and select pressure regulators for irrigation systems (farms, nurseries, greenhouses, sprinkler and drip systems).
- Guide manufacturers in design, marking and production to meet consistent safety and performance criteria.
- Define test procedures for laboratories and QA teams verifying conformity, accuracy and durability.
- Support procurement and technical specifications for irrigation equipment suppliers and system integrators.
- Inform maintenance and replacement decisions by installers and irrigation contractors.
Who uses this standard
- Valve manufacturers and product designers
- Test laboratories and certification bodies
- Irrigation system designers, contractors and equipment purchasers
- Agricultural engineers and facility managers
Related standards
Normative references include:
Keywords: ISO 10522:2021, pressure-regulating valves, direct-acting pressure regulator, irrigation systems, DN 100, agricultural irrigation, valve testing, accuracy levels.
