ISO 18471:2015

Agricultural irrigation equipment - Filters - Verification of filtration grade

ISO 18471:2015 a test method for the verification of filtration grade of filters intended for operation in agricultural irrigation systems. It is intended to be used for verifying the filter manufacturer's declaration about the filtration grade of a specific filter. This test method uses a Clogging Capacity Meter (CCM) device to compare the filtration grade of the filter under test against the filtration grade of a test filtration screen. NOTE This test method may also be used by a filter manufacturer to determine the filtration grade.

Matériel agricole d'irrigation — Filtres — Vérification du grade de filtration

General Information

• Status: Published
• Publication Date: 18-Oct-2015
• ICS: 65.060.35 - Irrigation and drainage equipment
• Technical Committee: ISO/TC 23/SC 18 - Irrigation and drainage equipment and systems
• Drafting Committee: ISO/TC 23/SC 18 - Irrigation and drainage equipment and systems
• Current Stage: 9093 - International Standard confirmed
• Start Date: 18-Mar-2021
• Completion Date: 13-Dec-2025

Overview

ISO 18471:2015 specifies a laboratory test method for verification of filtration grade of filters used in agricultural irrigation systems. The standard defines how to use a Clogging Capacity Meter (CCM) to compare a filter under test against a calibrated test filtration screen and to confirm a filter manufacturer’s declared filtration grade (expressed in micrometres, μm). The method can also be used by manufacturers to determine filtration grade.

Key topics and technical requirements

• Test principle: Two CCM units (upstream and downstream of the test filter) run simultaneously. Each CCM uses a defined test screen and the time to reach a specified pressure loss is recorded.
• CCM components: Sampler (screen housing, replaceable filtering screen, flow regulator) and control unit (pressure gauges, differential pressure gauge, count-up timer with 0.01 min resolution).
• Operating parameters:
  • CCM flow rate: 10 l/min (flow regulator accuracy ±2 %).
  • Target pressure loss for timing: 0.5 bar across each CCM test screen.
  • Pressure measurement accuracy: ±1 %; flow accuracy: ±2 %.
• Pass criterion: Calculate the ratio t_down / t_up (time for downstream CCM divided by time for upstream CCM). An average ratio ≥ 5 (from ten repetitions) indicates the declared filtration grade is correct.
• Test screens: CCM test screens are 316 stainless steel, plain-woven square mesh. The standard provides a table of typical aperture widths (range approximately 60 μm to 300 μm) and corresponding mesh/wire specifications.
• Procedure highlights:
  • Adjust system inlet pressure (initially 4.0 bar, then 3.0–4.0 bar for testing) and set the filter flow to the midpoint of the manufacturer’s declared range.
  • Record initial clean-filter pressure loss, replace filter medium with new identical medium before testing, and monitor during test.
  • Abort conditions: filter pressure loss increases by 0.5 bar over the clean state; special discontinuation guidance if results are extremely fast or slow.

Applications and users

ISO 18471:2015 is intended for:

• Filter manufacturers verifying or determining declared filtration grades.
• Independent test laboratories performing conformity verification and quality control.
• Irrigation equipment specifiers and purchasers who need validated filtration performance data for system design.
• Certification bodies and agricultural OEMs requiring standardized, repeatable verification of filter performance.

Practical benefits include consistent, repeatable verification of particle retention characteristics to protect emitters, nozzles and downstream irrigation components.

Related standards

• ISO 9644 - Pressure losses in irrigation valves (test method) (normative reference for pressure taps)
• ISO 9045 - Industrial screens and screening - Vocabulary
• ISO 80000-1 - Quantities and units (units used in standard)

Keywords: ISO 18471:2015, filtration grade, Clogging Capacity Meter, CCM, agricultural irrigation filters, verification of filtration grade, test method, filtration screens, pressure loss, flow rate.

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 18471
First edition
2015-10-15
Agricultural irrigation equipment —
Filters — Verification of filtration grade
Matériel agricole d’irrigation — Filtres — Vérification du grade de
filtration
Reference number
©
ISO 2015
© ISO 2015, Published in Switzerland
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form
or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior
written permission. Permission can be requested from either ISO at the address below or ISO’s member body in the country of
the requester.
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ii © ISO 2015 – All rights reserved

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Summary of the test method . 2
5 CCM structure and operation . 2
5.1 Construction . 2
5.1.1 Sampler (1) . 2
5.1.2 Control unit (2) . 2
5.2 Mode of operation . 2
6 CCM test screen characteristics . 3
7 ccuracy of measurements. 4
8 Test system layout . 4
9 Test procedure . 5
Bibliography . 7
Foreword
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different types of ISO documents should be noted. This document was drafted in accordance with the
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Attention is drawn to the possibility that some of the elements of this document may be the subject of
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Barriers to Trade (TBT) see the following URL: Foreword - Supplementary information.
The committee responsible for this document is ISO/TC 23, Tractors and machinery for agriculture and
forestry, Subcommittee SC 18, Irrigation and drainage equipment and systems.
iv © ISO 2015 – All rights reserved

INTERNATIONAL STANDARD ISO 18471:2015(E)
Agricultural irrigation equipment — Filters — Verification
of filtration grade
1 Scope
This International Standard specifies a test method for the verification of filtration grade of filters
intended for operation in agricultural irrigation systems. It is intended to be used for verifying the filter
manufacturer’s declaration about the filtration grade of a specific filter.
This test method uses a Clogging Capacity Meter (CCM) device to compare the filtration grade of the
filter under test against the filtration grade of a test filtration screen.
NOTE This test method may also be used by a filter manufacturer to determine the filtration grade.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
ISO 9644, Agricultural irrigation equipment — Pressure losses in irrigation valves — Test method
3 Terms and definitions
For the purpose of this document, the following terms and def
...