1、 ISO 2013 Agricultural irrigation equipment Filters for microirrigation Part 3: Automatic flushing strainer-type filters and disc filters Matriel agricole dirrigation Filtres pour micro-irrigation Partie 3: Filtres tamis et filtres disque auto-nettoyants INTERNATIONAL STANDARD ISO 9912-3 Second edit
2、ion 2013-10-01 Reference number ISO 9912-3:2013(E) ISO 9912-3:2013(E)ii ISO 2013 All rights reserved COPYRIGHT PROTECTED DOCUMENT ISO 2013 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 m
3、echanical, 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 ISOs member body in the country of the requester. ISO copyright office Case postale 56 CH-1211 Geneva 20 Tel. + 41 22 74
4、9 01 11 Fax + 41 22 749 09 47 E-mail copyrightiso.org Web www.iso.org Published in Switzerland ISO 9912-3:2013(E) ISO 2013 All rights reserved iii Contents Page Foreword iv 1 Scope . 1 2 Normative references 1 3 Terms and definitions . 1 4 Marking 2 5 General requirements . 2 6 Design and constructi
5、on requirements 2 6.1 Mandatory requirements . 2 6.2 Optional features . 4 7 Performance tests . 4 7.1 General . 4 7.2 Volume of flushing water and duration of flushing . 5 7.3 Operation of the flushing control mechanism . 5 7.4 Operation of the protective mechanism 6 8 Performance tests after long
6、term simulated use 7 8.1 Multiple flushing cycles procedure 7 8.2 Tests following the multiple flushing cycles 7 9 Information to be supplied by the filter manufacturer 8 ISO 9912-3:2013(E) Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standa
7、rds 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 organ
8、izations, 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
9、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. www.iso.org/directiv
10、es Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Intr
11、oduction and/or on the ISO list of patent declarations received. www.iso.org/patents Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement. The committee responsible for this document is ISO/TC 23, Tractors and machinery for agr
12、iculture and forestry, Subcommittee SC 18, Irrigation and drainage equipment and systems. This second edition cancels and replaces the first edition (ISO 9912-3:1992), which has been technically revised. ISO 9912 consists of the following parts, under the general title Agricultural irrigation equipm
13、ent Filters for microirrigation: Part 1: Terms, definitions and classification Part 2: Strainer-type filters and disc filters Part 3: Automatic flushing strainer-type filters and disc filters A fourth part on granulated media filters is planned.iv ISO 2013 All rights reserved INTERNATIONAL ST ANDARD
14、 ISO 9912-3:2013(E) Agricultural irrigation equipment Filters for microirrigation Part 3: Automatic flushing strainer-type filters and disc filters 1 Scope This part of ISO 9912 specifies general construction requirements and test methods for automatic flushing strainer-type filters and disc filters
15、 (hereinafter called “filters”) intended for operation in agricultural irrigation systems. It does not cover the aspects of filtration ability, efficiency and capacity (like quality of filtered water or time of operation before filter becomes entirely clogged). NOTE 1 The parameters of filtration ab
16、ility, efficiency and capacity, their definitions and their test methods are to be included in a separate ISO International Standard or Technical Report. The test methods will be described in that document, using water as defined by the client, to characterize the filter properties during operation
17、with this water, or with water defined by the tester or the client, for comparison between various filters under identical operating conditions. NOTE 2 ISO 9912-2 covers strainer-type filters and disc filters in general (see Clause 5). 2 Normative references The following documents, in whole or in p
18、art, 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 9912-1, Agricultural irrigation equipment Fi
19、lters for micro-irrigation Part 1: Terms, definitions and classification ISO 9912-2: 1) , Agricultural irrigation equipment Filters for microirrigation Part 2: Strainer-type filters and disc filters 3 Terms and definitions For the purposes of this part of ISO 9912, the following terms and definition
20、s apply, together with the relevant definitions in ISO 9912-1 and ISO 9912-2. 3.1 automatic flushing filter filter in which both the initiation and the termination of discrete flushing cycles are activated automatically 3.2 duration of automatic flushing cycle period of time during which water and c
21、logging material are flushed out 1) To be published. (Revision of ISO 9912-2:1992) ISO 2013 All rights reserved 1 ISO 9912-3:2013(E) 3.3 flushing control mechanism mechanism which initiates and terminates the flushing action of a filter 3.4 flushing valve valve through which flushing water is discha
22、rged from a filter 3.5 minimum working pressure lowest pressure immediately upstream from a filter that is recommended by the manufacturer to ensure proper operation 3.6 minimum filtering pressure lowest working pressure immediately upstream from a filter, declared by the manufacturer, which ensures
23、 the proper functioning of a filter while in the filtering mode 3.7 minimum flushing pressure lowest working pressure immediately upstream from a filter, declared by the manufacturer, which ensures proper flushing while in the flushing mode 3.8 prefiltration element part of a filter intended to prot
24、ect the filter element and cleaning mechanism by collecting especially large particles of the clogging material prior to their reaching the main filter element 3.9 protective mechanism mechanism that prevents repeated flushings of a filter caused either by mechanical failure in the flushing control
25、mechanism or by some other fault 3.10 volume of flushing water volume of water flushed from a filter during one flushing cycle 4 Marking Each filter shall bear all the markings specified in ISO 9912-2:, Clause 4. The filter markings shall also include a calibrated permanent scale which shows the ind
26、ividual setting positions, where these exist, for the various options of adjustment of the automatic flushing cycle. 5 General requirements All the requirements that are included in ISO 9912-2 apply to automatic flushing filters, in addition to the specific requirements and tests that are included i
27、n this part of ISO 9912. 6 Design and construction requirements 6.1 Mandatory requirements Models of typical automatic flushing filters are shown in Figure 1 and Figure 2.2 ISO 2013 All rights reserved ISO 9912-3:2013(E) Key 1 inlet 5 filter element 2 outlet 6 flushing valve 3 filter housing 7 flush
28、ing control mechanism 4 filter housing cover 8 prefilter Figure 1 Typical structure of an automatic flushing strainer-type filter Key 1 inlet 2 outlet 3 filter housing 4 disc elements Figure 2 Typical structure of an automatic flushing disc filter The construction of an automatic self-cleaning filte
29、r shall comply with the following requirements. a) The flushing control system shall be a part of the filter assembly and shall be supplied by the manufacturer together with the filter, or shall be a part produced by the filter manufacturer and supplied according to special demand of the customer. A
30、lternatively, the flushing control system may be manufactured by a third party, provided that it is approved by the filter manufacturer and is included in the information supplied by the manufacturer (see Clause 9). ISO 2013 All rights reserved 3 ISO 9912-3:2013(E) b) The construction of the filter
31、shall allow manual actuation of automatic flushing in the event of failure of the automatic flushing control mechanism. c) The flushing control mechanism shall allow manual flushing at any time, irrespective of the conditions that apply to automatic flushing. d) The construction of the filter housin
32、g shall permit dismantling for maintenance (or for cleaning, if the filter is also designed for manual cleaning). e) The coordination of the flushing operation and the opening of the flushing valve shall prevent water flowing out of the flushing valve unless the filter is being cleaned. During flush
33、ing, it shall be open for at least one full flushing operation. f) The initiation and termination of flushing may be activated by pressure differential, by duration of filtration, by volume of water filtered, by another physical quantity or by a combination of these. g) When a prefiltration element
34、exists, the maximum pressure drop across it shall be less than the safe maximum pressure drop of the filter assembly. 6.2 Optional features In addition, the following construction features are recommended. a) The filter may be fitted with a device that enables adjustment of the preset value of the f
35、lushing control mechanism for initiation of the flushing cycle, for controlling the duration and termination of the flushing cycle. b) The filter may be equipped with a protective mechanism that prevents repeated flushings (see 3.9). c) All hydraulically operated accessories of the filter should be
36、operated using filtered water, with the exception of the inlet pressure signal which may come from non-filtered water. d) The design of a prefiltration element, its filtering area, the size of water passages and their shape should be appropriate for the water quality for which the filter is intended
37、. NOTE 1 The prefiltration element is an optional component. e) The prefiltration element should be an integral part of the filter while being tested according to Clauses 7 and 8. (This element is not intended to be tested separately.) NOTE 2 The prefiltration element is not automatically flushed. 7
38、 Performance tests 7.1 General The tests and the requirements given in Clauses 7 and 8 apply to f ilters whose desig n or manner of operat ion are in accordance with the concept inferred by the test process described in the applicable clause. The concepts of flushing cycle and flushing duration may
39、not apply to all filters within the scope of this part of ISO 9912 (for example: automatic continuous-flushing filters). In such cases, the test procedure shall be adapted to the specific filter design and the declaration in the manufacturers literature. However, it is important to ensure that the v
40、olume of flushing water shall not exceed that declared by the manufacturer by more than 7 %. A filter that does not contain an integral control system shall be tested together with a control system indicated in the manufacturers literature, as a combined system. In this case, the results of the test
41、 will apply only to the combination of the tested filter and the specific control system.4 ISO 2013 All rights reserved ISO 9912-3:2013(E) 7.2 Volume of flushing water and duration of flushing 7.2.1 Test at specific operating pressures Connect the filter as described in the manufacturers instruction
42、s to a test assembly, simulating field installation. Ensure that the test assembly is capable of supplying at least twice the maximum flushing volume at the nominal pressure, as declared by the manufacturer. Attach a collection vessel to the flushing opening of the filter for collecting the flush wa
43、ter. Set the pressure at the filter inlet to the minimum flushing pressure and initiate a flushing cycle manually. Measure the volume of the collected flushing water and the time from the moment the flush valve begins to open to the time it closes. Repeat the test at the nominal pressure. The follow
44、ing requirements shall be met: a) the volume of water measured in each of the tests shall not exceed the volume of flushing water declared by the manufacturer by more than 7 %; b) the duration of flushing measured shall not deviate from the flushing duration declared by the manufacturer by more than
45、 15 %. 7.2.2 Test at the minimum flow rate Connect the filter as described in 7.2.1. Ensure that the test assembly is capable of supplying at least the maximum flow rate recommended at a pressure differential equal to the safe maximum pressure drop. Attach a collection vessel to the flushing outlet
46、of the filter for collecting the flush water. Operate the filter at a flow rate equal to the minimum recommended flow rate, with the pressure at the filter set to the critical pressure drop before failure. Manually activate the flushing mechanism twice. At each activation measure the volume of flush
47、 water and the time from the moment the flush valve begins to open to the time it closes. The following requirements shall be met: a) the flushing mechanism shall operate satisfactorily (the flushing process is completed); b) the volume of water measured in each of the tests shall not exceed the vol
48、ume of flushing water declared by the manufacturer by more than 7 %; c) the duration of flushing measured shall not deviate from the flushing duration declared by the manufacturer by more than 15 %. 7.3 Operation of the flushing control mechanism 7.3.1 Mechanism activated by pressure differential se
49、nsor Disconnect the “low” pressure connection of the pressure differential sensor and connect it to an external pressure source. Leave the “high” pressure connection as connected for regular filter operation. Apply a pressure equal to the minimum filtering pressure at the filter inlet and at the external pressure source. Gradually reduce the pressure at the external pressure source until the flushing operation is performed. Repeat the test once with a filter inlet pressure at midrange between the minimum filtering
