ISO 10522:2021

INTERNATIONAL ISO
STANDARD 10522
Second edition
2021-08
Agricultural irrigation equipment —
Direct-acting pressure-regulating
valves
Matériel agricole d'irrigation — Vannes de régulation de la pression à
action directe
Reference number
©
ISO 2021
© ISO 2021
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ii © ISO 2021 – All rights reserved

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Pressure regulator classification . 3
4.1 According to construction of regulation assembly . 3
4.2 According to construction of pressure regulator . 3
4.3 According to regulated pressure at zero flow . 3
4.4 According to accuracy level [see 7.5.2.4 b)] . 3
5 Marking . 4
6 Technical characteristics . 4
6.1 General . 4
6.2 Pressure regulator body . 4
6.3 Adjustment assembly . 5
6.4 Connections . 5
6.5 Adjustable stop . 5
7 Mechanical and functional tests . 5
7.1 Overview . 5
7.2 General . 6
7.3 Regulation uniformity (in non-adjustable pressure regulators) . 6
7.4 Tightness of pressure regulator with adjustable stop . 7
7.5 Regulation curve . 7
7.5.1 Installation . 7
7.5.2 Test results and requirements . 8
7.5.3 Single-range pressure regulators (class 4.1.1) . 9
7.5.4 Multi-range pressure regulators (class 4.1.2) . 9
7.5.5 Single-range adjustable pressure regulators (class 4.1.3) . 9
7.5.6 Multi-range adjustable pressure regulators (class 4.1.4) . 9
7.6 Regulated pressure as function of pressure regulator adjustment in pressure
regulators of classes 4.1.3 and 4.1.4 . 9
7.7 Regulated pressure at zero flow (in pressure regulators of class 4.3.2) . 9
7.8 Regulated pressure as function of inlet pressure at constant flow rate .10
7.8.1 General.10
7.8.2 Plotting pressure curves .10
7.9 Regulation curve of integral pressure regulators (class 4.2.2) .10
7.10 Pressure loss .11
7.11 Resistance of pressure regulator body to internal hydrostatic pressure .11
7.11.1 General.11
7.11.2 Metal-body pressure regulators .11
7.11.3 Plastics-body pressure regulators .11
8 Durability .12
8.1 On/off cycles .12
8.2 Changing condition cycles .12
8.2.1 General.12
8.2.2 For ordinary pressure regulators .12
8.2.3 For integral pressure regulators .12
8.2.4 Requirement for ordinary and integral pressure regulators .13
9 Information to be supplied by the manufacturer .13
9.1 General information .13
9.2 Operational data .13
Annex A (informative) Figures .14
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
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iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 23, Tractors and machinery for agriculture
and forestry, Subcommittee SC 18, Irrigation and drainage equipment and systems.
This second edition cancels and replaces the first edition (ISO 10522:1993), which has been technically
revised.
The main changes compared to the previous edition are as follows.
— The range of pressure regulators sizes has been extended up to DN 100 (4").
— The water temperature of the irrigation system has been harmonized to 60 °C.
— The normative references have been updated.
— The terms and definitions have been updated.
— The testing water temperature range has been updated to 4 °C to 35 °C.
— The face-to-face distance of the flanged bodies of the pressure regulators has been updated to
±4 mm for plastics-body regulators.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
iv © ISO 2021 – All rights reserved

INTERNATIONAL STANDARD ISO 10522:2021(E)
Agricultural irrigation equipment — Direct-acting
pressure-regulating valves
1 Scope
This document specifies construction and performance requirements and test methods for direct-
acting pressure-regulating valves (hereinafter "pressure regulators") intended for operation in
irrigation systems, with water at temperatures not exceeding 60 °C, which can contain fertilizers and
chemicals of types and in concentrations commonly used in agricultural irrigation.
This document applies to pressure regulators in nominal sizes up to and including 100 mm (4 in).
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 7-1, Pipe threads where pressure-tight joints are made on the threads — Part 1: Dimensions, tolerances
and designation
ISO 7005-1, Pipe flanges — Part 1: Steel flanges for industrial and general service piping systems
ISO 7005-2, Metallic flanges — Part 2: Cast iron flanges
ISO 9644, Agricultural irrigation equipment — Pressure losses in irrigation valves — Test method
1)
ISO 24649:—, Agricultural irrigation equipment — Manually and hydraulically operated plastics valves
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:
...