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1、BRITISH STANDARD BS EN 25264-3:1994 ISO 5264-3: 1979 Pulps Laboratory beating Part 3: Jokro mill method The European Standard EN 25264-3:1994 has the status of a British Standard UDC 676.1:542.67 Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 03 09:26:47 GMT+00:00 2006, Uncontrolled Copy, (c) B
2、SI BS EN 25264-3:1994 This British Standard, having been prepared under the direction of the Paper and Printing Standards Policy Committee, was published under the authority of the Standards Board and comes into effect on 15 October 1994 BSI 01-2000 The following BSI references relate to the work on
3、 this standard: Committee reference PAM/11 Special announcement in BSI News September 1993 ISBN 0 580 23139 9 Cooperating organizations The European Committee for Standardization (CEN), under whose supervision this European Standard was prepared, comprises the national standards organizations of the
4、 following countries: AustriaOesterreichisches Normungsinstitut BelgiumInstitut belge de normalisation DenmarkDansk Standard FinlandSuomen Standardisoimisliito, r.y. FranceAssociation franaise de normalisation GermanyDeutsches Institut fr Normung e.V. GreeceHellenic Organization for Standardization
5、IcelandTechnological Institute of Iceland IrelandNational Standards Authority of Ireland ItalyEnte Nazionale Italiano di Unificazione LuxembourgInspection du Travail et des Mines NetherlandsNederlands Normalisatie-instituut NorwayNorges Standardiseringsforbund PortugalInstituto Portugus da Qualidade
6、 SpainAsociacin Espaola de Normalizacin y Certificacin SwedenStandardiseringskommissionen i Sverige SwitzerlandAssociation suisse de normalisation United KingdomBritish Standards Institution Amendments issued since publication Amd. No.DateComments Licensed Copy: sheffieldun sheffieldun, na, Fri Nov
7、03 09:26:47 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS EN 25264-3:1994 BSI 01-2000i Contents Page Cooperating organizationsInside front cover National forewordii Foreword2 0Introduction3 1Scope3 2Field of application3 3References3 4Principle3 5Apparatus and auxiliary materials3 6Preparation of sa
8、mple3 7Procedure4 8Test report5 Annex The Jokro mill6 Annex ZA (normative) Normative references to international publications with their relevant European publications8 National annex NA (informative) Committees responsibleInside back cover National annex NB (informative) Cross-referencesInside back
9、 cover Figure The Jokro mill7 Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 03 09:26:47 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS EN 25264-3:1994 ii BSI 01-2000 National foreword This British Standard has been prepared under the direction of the Paper and Printing Standards Policy Committe
10、e and is the English language version of EN 25264-3:1994 Pulps Laboratory beating Part 3: Jokro mill method, published by the European Committee for Standardization (CEN). It is identical with ISO 5264-3:1979 published by the International Organization for standardization (ISO). EN 25264-3 was produ
11、ced as a result of international discussion in which the UK took an active part. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself
12、confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, the EN title page, pages 2 to 8, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated.
13、 This will be indicated in the amendment table on the inside front cover. Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 03 09:26:47 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EUROPEAN STANDARD NORME EUROPNNE EUROPISCHE NORM EN 25264-3 June 1994 UDC 676.1:542.67 Descriptors: Paper pulps, test s
14、pecimen conditioning, refining, laboratory equipment English version Pulps Laboratory beating Part 3: Jokro mill method (IEC 5264-3:1979) Ptes Raffinage de laboratoire Partie 3: Mthode au moulin Jokro (ISO 5264-3:1979) Zellstoff Labormahlung Teil 3: Jokro-Mlhe-Verfahren (ISO 5264-3:1979) This Europe
15、an Standard was approved by CEN on 1994-06-27. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerni
16、ng such national standards may be obtained on application to the Central Secretariat or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own lan
17、guage and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and
18、 United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels 1994 Copyright reserved to CEN members Ref. No. EN 25264-3:1994 E Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 03
19、09:26:47 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 25264-3:1994 BSI 01-2000 2 Foreword This European Standard has been taken over by CEN/TC 172, Pulp, paper and board, from the work of ISO/TC 6, Paper, board and pulps, of the International Organization for Standardization (ISO). This document wa
20、s submitted to the Unique Acceptance Procedure (UAP) and was approved without any modification. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by December 1994, and conflicting national standards sh
21、all be withdrawn at the latest by December 1994. In accordance with the CEN/CENELEC Internal Regulations, the following countries are bound to implement this European Standard: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Port
22、ugal, Spain, Sweden, Switzerland and United Kingdom. Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 03 09:26:47 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 25264-3:1994 BSI 01-20003 0 Introduction It has been agreed that the ultimate aim of standardization of laboratory beating should be to d
23、evelop one test method which is internationally acceptable and which, if possible, allows the energy consumption during beating to be measured. For practical reasons it has not proved possible to achieve this at present. Therefore, as an interim measure, in view of the widespread use of the followin
24、g methods Valley beater, PFI mill, Jokro mill, it has been decided to provide agreed guidance on the use of these equipments in order to achieve consistency of results with each instrument. While all three methods will show a similar trend in respect of the pulp tested, the actual results cannot be
25、correlated between different types of beater1). The position will be kept under review, and the methods will be replaced by a single method as soon as practicable. 1 Scope This International Standard specifies a method, using a Jokro mill, for the laboratory beating of pulp. The description is limit
26、ed to the disintegrating and beating of the stock, the withdrawal and distribution of samples, and the beating equipment. The beating is a preliminary step in testing the physical properties of pulp. Part I specifies a method of laboratory beating using a Valley beater and Part II a method using a P
27、FI mill. 2 Field of application In principle, this method is applicable to all kinds of pulp. NOTEIn practice, the method may not give satisfactory results with certain extremely long-fibred pulps, such as cotton linter. 3 References ISO 638, Pulps Determination of dry matter content. ISO 4119, Pulp
28、s Determination of stock concentration (Rapid method). ISO 5263, Pulps Laboratory wet disintegration2). 4 Principle A measured amount of pulp of specified stock concentration is beaten between the inner wall of a cylindrical beating box which-revolves with a planetary rotation around a central shaft
29、, and a grooved roll loosely placed in the box. 5 Apparatus and auxiliary materials Ordinary laboratory equipment and 5.1 Jokro mill, as described in the Annex. 5.2 Standard distintegrator, as described in ISO 5263. 5.3 Balance, capable of weighing the sample to an accuracy of 0,2 g. 5.4 Distilled w
30、ater, or water of similar quality. NOTEDistilled water, or water of similar quality, is particularly. recommended with a view to obviating any difficulties that might arise from the use of different qualities of water by the interested parties. 6 Preparation of sample If the pulp is wet or air-dry,
31、weigh out a sample for dry matter determination in accordance with ISO 638. If the pulp is in slush form, determine the dry matter content in accordance with ISO 4119. Take an amount of the pulp corresponding to 16 0,5 g of oven-dry pulp (do not cut the pulp, and avoid the use of cut edges). If the
32、sample is in the form of machine-dried sheets or flash-dried slabs, soak the pulp thoroughly in 0,5 litre of water (see 5.4) at room temperature for not less than 4 h. Tear the soaked pulp into pieces approximately 25 mm 25 mm in size. It is essential that the pulp be thoroughly softened by soaking,
33、 to ensure that the preliminary disintegration results in a minimal beating effect. Wet pulps may be disintegrated without soaking. 1) Should one of the three methods listed become the future standard method, the method chosen should be the one which works in the most economical way and yields the h
34、ighest reproducibility of results obtained in different laboratories. At present, some countries are of the opinion that the PFI mill described in ISO 5264/II meets these requirements best of all. 2) At present at the stage of draft. Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 03 09:26:47 GM
35、T+00:00 2006, Uncontrolled Copy, (c) BSI EN 25264-3:1994 4 BSI 01-2000 7 Procedure 7.1 Disintegration Transfer the wet-pulp sample, and the water used for disintegration, to the disintegrator (5.2). Add water at 20 5 C to give a total volume of 1 100 25 ml; the pulp concentration will then be about
36、1,5 % (m/m). Set the revolution counter to zero. Switch the motor on and allow the disintegrator to run for a few seconds. Switch the motor off and, before the propeller stops, switch on again. For pulps having an initial dry matter content of 20 % (m/m) or more allow the propeller to make 30 000 re
37、volutions. For pulps having an initial dry matter content of less than 20 % (m/m), allow the propeller to make 10 000 revolutions. When the propeller has stopped, check that the pulp has been completely disintegrated. NOTE 1Where necessary for climatic reasons, a temperature of 25 5 C may be used, p
38、rovided that this is noted in the test report. NOTE 2Ensure that the pulp is completely disintegrated. Pulps that are difficult to disintegrate, such as unbleached sulphate pulp, may require a longer time than that specified above. NOTE 3A sample disintegrated as described above may not be regarded
39、as a sample of unbeaten pulp disintegrated in accordance with ISO 5263. 7.2 Thickening After disintegration, drain the pulp suspension on a Buchner funnel to a concentration of approximately 20 % (m/m). To avoid loss of any fibres, refilter the filtrate through the fibre mat, if necessary several ti
40、mes. Dilute the thickened pulp with water to a total mass of 265 5 g, corresponding to a 6 % (m/m) stock concentration. 7.3 Beating Beating conditions: Rotational frequency of the vertical shaft of the Jokro mill: 2,50 0,05 s1 Bring the beating elements of the Jokro mill (5.1) and the pulp suspensio
41、n to a temperature of 20 5 C. Transfer the pulp suspension, prepared in accordance with 7.2, to the cylindrical beating box, and distribute the pulp as evenly as possible around the grooved roll previously placed in the unit with the running base downwards. Place the lid on the box, and ensure that
42、the rubber ring fits tightly. In each set, the box, lid and grooved roll shall all bear the same number. Place the unit in a holder of the turntable, and fix it with a clamp. Distribute the boxes symmetrically on the holders, to avoid one-sided loading of the mill. Thus, if beating is effected with
43、only one unit, or with five units, a further unit shall be mounted, containing the same amount of fibre water mixture as a weight balance. When the beating boxes are placed in the Jokro mill, and the mill has been closed, set the mill into operation, and adjust the rotational frequency of the contro
44、l shaft to exactly 2,50 0,05 s1 as the beating pressure is dependent upon this. The time of beating required for the desired beating point depends upon the beating resistance of the pulp, and may vary according to the type of pulp. The following is an example of a schedule for sample removal: The be
45、ating time (duration between starting and stopping the motor) shall be kept to within 5 s. When the beating time has been obtained for a certain unit, switch off the motor, and remove the box concerned. At the same time, read off from the counter, the value for the number of central shaft revolution
46、s and note it. After a standstill, which should if possible not exceed approximately 1 min, continue the beating, but ensure that the units which remain in the mill are arranged symmetrically; this is achievable by inserting an additional unit, made up with the usual fibre/water mixture. Transfer th
47、e stock to a measuring cylinder with a volume of at least 1 000 ml. Rinse the beating box and add the rinsings to the cylinder. Dilute the stock with water to 1 100 25 ml, and clear the pulp suspension by disintegrating it in the standard disintegrator (5.2) using 10 000 revolutions of the propeller
48、. NOTE 1When the mill is started, knocking may be heard; this should disappear after a few rotations, depending upon the evenness of the original distribution of the pulp. NOTE 2After beating, clean the beating boxes thoroughly with water and, if necessary, with a pitch solvent. NOTE 3If the drainab
49、ility is measured, this should be done with a minimum of delay. Sulphite pulps and other pulps that are easily beaten:10, 30, 40, 70 min Sulphate pulps and other pulps that beat more slowly:15, 30, 60, 90, 120 min Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 03 09:26:47 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 25264-3:1994 BSI 01-20005 8 Test report The test report shall indicate the following particulars: a) reference to this International Standard; b) all the indications necessary for com