1、BRITISH STANDARD BS 7804-1: 1995 ISO 9884-1: 1994 Tea sacks Part 1: Specification for a reference sack for palletized and containerized transport of teaBS7804-1:1995 This British Standard, having been prepared under the directionof the Consumer Products and Services Sector Board (W/-), was published
2、 underthe authority of the Standards Board and comes intoeffect on 15April1995 BSI 11-1999 The following BSI references relate to the work on this standard: Committee reference AW/8 Draft for comment 93/506928 DC ISBN 0 580 23951 9 Committees responsible for this British Standard The preparation of
3、this British Standard was entrusted to Technical Committee AW/8, Tea, upon which the following bodies were represented: Campden Food and Drink Research Association Ministry of Agriculture, Fisheries and Food Natural Resources Institute Tea Trade Technical Committee United Kingdom Tea Association Ame
4、ndments issued since publication Amd. No. Date CommentsBS7804-1:1995 BSI 11-1999 i Contents Page Committees responsible Inside front cover National foreword ii Introduction 1 1 Scope 1 2 Normative references 1 3 Definitions 1 4 Sampling 1 5 Requirements 2 Annex A (normative) Method of determination
5、of the grammage of constituents of barrier ply laminate 4 Annex B (informative) Results of interlaboratory test 5 Table 1 Sack dimensions 2 Table 2 Sack composition and ply grammage 3 Table 3 Strength requirements 3 Table B.1 Grammage of constituents of barrier ply laminate 5 List of references Insi
6、de back coverBS7804-1:1995 ii BSI 11-1999 National foreword This Part of BS7804has been prepared under the direction of the Consumer Products and Services Sector Board. It is identical with ISO 9884-1:1994 Tea sacks Specification Part 1: Reference sack for palletized and containerized transport of t
7、ea, published by the International Organization for Standardization (ISO). This Part of BS7804 implements an agreement, to which the United Kingdom was a party, reached in Subcommittee 8, Tea, of Technical CommitteeTC 34, Agricultural food products, of ISO. The United Kingdom provides the secretaria
8、t for this subcommittee. Cross-references International Standard Corresponding British Standard Normative ISO 536:1976 BS 3432:1980 Method for determination of grammage of paper and board (Identical) BS 3951 Freight containers Part 1 General ISO 668:1988 Section 1.1:1989 Specification for Series 1 f
9、reight containers: Classification, dimensions and ratings (Identical) ISO 830:1981 Section 1.4:1983 Glossary of terminology (Identical) ISO 1924-2:1985 BS 4415 Determination of the tensile properties of paper and board Part 2:1986 Constant rate of elongation method (Identical) ISO 1974:1990 BS 4468:
10、1990 Method for determination of the internal tearing resistance of paper (Identical) ISO 4797:1981 BS 6352:1983 Specification for flasks with ground glass joints (Identical) ISO 6590-1:1983 BS EN 26590 Packaging Sacks Vocabulary and types Part 1:1993 Paper sacks (Identical) ISO 6591-1:1984 BS EN 26
11、591 Packaging Sacks Description and method of measurement Part 1:1993 Empty paper sacks (Identical) ISO 7023:1983 BS EN 27023:1993 Packaging Sacks Method of sampling empty sacks for testing (Identical) Informative ISO 5725:1986 BS 5497 Precision of test methods Part 1:1987 Guide for the determinatio
12、n of repeatability and reproducibility for a standard test method by inter-laboratory tests (Identical)BS7804-1:1995 BSI 11-1999 iii The Technical Committee has reviewed the provisions of ISO 2758:1983, ISO3676:1983 and ISO 8351-1:1994, to which reference is made in the text, and has decided that th
13、ey are acceptable for use in conjunction with this standard. Related British Standards to ISO2758and ISO3676are BS3137:1972and BS6884:1987respectively. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their corr
14、ect application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i to iv, pages 1 to 6, an inside back cover and a back cover. This standard has been updated (see copyri
15、ght date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.iv blankBS7804-1:1995 BSI 11-1999 1 Introduction The plywood tea chest was for many years the preferred and standard shipping unit for tea. However, the growing scarcity and co
16、st of plywood in many producing countries has led in recent years to the use of alternatives based on more freely available and cheaper materials, such as paper and cardboard. Amongst the various alternative forms of bulk packing tested, multi-ply kraft paper sacks have found wide and growing accept
17、ance for the palletized and containerized transport of tea. One particular type of multi-ply paper sack with a polyethylene-bonded aluminium moisture and odour barrier has been developed following a number of transport and storage trials. It has been clearly shown to: withstand the handling and stre
18、sses involved in palletization, containerization, shipping and unpacking; adequately protect tea from the deleterious effect of moisture uptake and exposure to taint; load efficiently on to standard four-way entry pallets and into standard freight containers. This part of ISO9884specifies the materi
19、als, construction and dimensions of this sack, which is intended to act as a performance reference sack against which sacks of different materials and construction may be tested. Minimum requirements and performance tests for sacks intended for palletized and containerized transport of tea are speci
20、fied in ISO 9884-2 1) . It is anticipated that stronger, puncture-resistant materials (for example, cross-laminated high-density polyethylene) will permit the development and future specification of a reference sack capable of withstanding the stresses involved in handling and transport prior to pal
21、letization and containerization. 1 Scope This part of ISO9884specifies the materials, construction and dimensions of a reference sack (valve-pasted, flat, hexagonal-ended sack of stepped-end construction, formed from a stepped-end tube) suitable for the palletized and containerized transport of tea:
22、 on a four-way entry,1120mm 1120mm, flat, flush-ended pallet to fit the unit load size of1140mm 1140mm specified in ISO 3676; in freight containers of the dimensions specified in ISO 668, either closed and non-vented, or closed and corner-post vented (see ISO 830:1981, 4.1.1.1). 2 Normative referenc
23、es The following standards contain provisions which, through reference in this text, constitute provisions of this part of ISO9884. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this part of ISO9884are encoura
24、ged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and ISO maintain registers of currently valid International Standards. ISO 536:1976, Paper and board Determination of grammage. ISO 668:1988, Series 1 freight containers Classific
25、ation, dimensions and ratings. ISO 830:1981, Freight containers Terminology. ISO 1924-2:1985, Paper and board Determination of tensile properties Part 2: Constant rate of elongation method. ISO 1974:1990, Paper Determination of tearing resistance (Elmendorf method). ISO 2758:1983, Paper Determinatio
26、n of bursting strength. ISO 3676:1983, Packaging Unit load sizes Dimensions. ISO 4797:1981, Laboratory glassware Flasks with conical ground joints. ISO 6590-1:1983, Packaging Sacks Vocabulary and types Part 1: Paper sacks. ISO 6591-1:1984, Packaging Sacks Description and method of measurement Part 1
27、: Empty paper sacks. ISO 7023:1983, Packaging Sacks Method of sampling empty sacks for testing. ISO 8351-1:1994, Packaging Method of specification for sacks Part 1: Paper sacks. 3 Definitions For the purposes of this part of ISO 9884, the definitions given in ISO6590-1apply. 4 Sampling Samples shall
28、 have been taken in accordance with ISO 7023. 1) To be published.BS7804-1:1995 2 BSI 11-1999 5 Requirements 5.1 General requirements for materials The sack shall be made from either normal kraft paper for sacks (see ISO 6590-1:1983, 5.1 and 5.2.1) or extensible kraft paper for sacks (see ISO 6590-1:
29、1983, 5.2.2) together with barrier-coated paper (see ISO 6590-1:1983, 5.6.1) consisting of aluminium foil bonded to kraft paper for sacks with polyethylene. Normal kraft paper and extensible kraft paper shall not be used together in the same sack. All materials used in the construction of the sack (
30、paper, adhesive, barrier ply) shall be free from taint. No materials or substances containing chlorophenols or their derivatives shall be used. 5.2 Dimensions 5.2.1 Empty sack (lay-flat) dimensions The empty sack dimensions shall be as given inTable 1, defined and measured according to4.2.3 and clau
31、se 5 of ISO 6591-1:1984, and with the tolerances specified in ISO 8351-1. 5.2.2 Filled sack dimensions The filled sack dimensions shall not exceed those given in Table 1. Table 1 Sack dimensions 5.3 Construction The sack shall consist of: four plies of normal kraft paper for sacks or three plies of
32、extensible kraft paper for sacks as specified in Table 2; an inner aluminium-coated barrier ply with the aluminium facing the inside of the sack, as specified in Table 2; an external valve sleeve (see ISO 6590-1:1983, 4.4.2.3) made of the same material as the inner barrier ply; a tuck-in valve sleev
33、e pocket. 5.4 Ply grammage and strength 5.4.1 Ply grammage 5.4.1.1 Paper plies The grammage of paper plies (plies1to4for normal kraft paper sacks, plies1to3for extensible kraft paper sacks) shall comply with the minimum requirements given in Table 2 when determined in accordance with the method give
34、n in ISO 536. 5.4.1.2 Barrier ply The grammage of constituents of barrier (inner) ply (ply5for normal kraft paper sacks, ply4for extensible kraft paper sacks) shall comply with the minimum requirements given in Table 2 when determined in accordance with the method given inAnnex A. 5.4.2 Strength The
35、 mean values obtained by testing the number of sacks specified in ISO7023shall satisfy the requirements given in Table 3 when tested by the methods indicated. Dimensions in millimetres Dimension Empty sack Filled sack Sack length 1120 10 1 120 max. Sack width 720 5 560 max. Width of bottom 180 5 Val
36、ve sleeve width 180 5 Sack depth 205 max.BS7804-1:1995 BSI 11-1999 3 Table 2 Sack composition and ply grammage Table 3 Strength requirements Normal kraft paper sack Extensible kraft paper sack Sack composition Minimum grammage, g/m 2on dry basis Sack composition Minimum grammage, g/m 2on dry basis P
37、ly 1 (outer): wet strength kraft paper 70 Ply 1 (outer): wet strength extensible kraft paper 80 Ply 2: normal kraft paper 70 Ply 2: extensible kraft paper 80 Ply 3: normal kraft paper 70 Ply 3: extensible kraft paper 80 Ply 4: normal kraft paper 70 Ply 4 (inner): Ply 5 (inner): extensible kraft pape
38、r 60 normal kraft paper 60 polyethylene 20 polyethylene 20 aluminium 18,7 aluminium 18,7 Total 378,7 Total 338,7 Test method Normal kraft paper a Extensible kraft paper min. min. max. Tensile index (Nm/g) ISO 1924-2 MD 55 CD 30 45 35 Stretch (%) ISO 1924-2 MD 1,8 CD 4,0 8,0 5,0 9,0 8,0 Tensile energ
39、y absorption index (J/g) ISO 1924-2 MD 0,7 CD 0,9 2,2 1,3 Burst index (kN/g) ISO 2758 Wet 1,1 Dry 3,7 1,2 4,0 Tear index (mNm 2 /g) ISO 1974 MD/CD 10,0 12,0 a MD = machine direction; CD = cross directionBS7804-1:1995 4 BSI 11-1999 Annex A (normative) Method of determination of the grammage of consti
40、tuents of barrier ply laminate A.1 Principle Separation of a known area of dried barrier ply laminate into its three components by dissolution of the polyethylene in hot toluene. Drying and weighing of the separated paper and aluminium and determination of the polyethylene by difference. A.2 Reagent
41、 A.2.1 Toluene, analytical reagent grade. A.3 Apparatus Usual laboratory apparatus and, in particular, the following. A.3.1 Steam bath A.3.2 Round-bottomed flask, of capacity500ml, and with ground glass joint size 29/32 or 34/35, complying with ISO 4797, with condenser and any required adaptor. A.3.
42、3 Aluminium or silica dishes, of nominal capacity100ml. A.3.4 Oven, capable of operating at103 C 2 C. A.3.5 Desiccator, containing silica gel. A.4 Test sample A.4.1 Remove and smooth until flat the innerbarrier ply from each sack sampled. Cutfromeachasquare test sample measuring10cm 10cm (0,01 m 2 )
43、. A.4.2 Heat the test sample in the oven (A.3.4) set at103 C for1h. Remove from the oven, cool in the desiccator (A.3.5) for1h and weigh to the nearest0,005g. A.5 Procedure A.5.1 Heat two of the dishes (A.3.3) in the oven(A.3.4) set at103 C for1h. Remove from the oven and cool in the desiccator (A.3
44、.5) until ready for use. A.5.2 Cut the test sample (A.4.2) into four pieces, and place them in the flask (A.3.2). Using a measuring cylinder, transfer150ml of the toluene(A.2) to the flask. Place the flask on the steam bath(A.3.1), fit the condenser and leave for3h. A.5.3 Remove the flask and conden
45、ser from the steam bath and allow them to cool to room temperature. Take off the condenser, then remove the separated paper and aluminium foil from the flask with tongs. Hold each above the surface of the toluene in the flask, and rinse with fresh toluene into the flask. Then place the paper and the
46、 aluminium into the separate dried dishes, each previously weighed to the nearest0,005g. Dry the dishes and their contents in the oven set at103 C for1h. Allow them to cool in the desiccator, then weigh them to the nearest0,005g. A.5.4 Discard the toluene solution containing the polyethylene. A.6 Ex
47、pression of results Report the individual results obtained for each sack sampled, together with the arithmetic mean. A.6.1 Grammage of paper The grammage of the paper, expressed in grams per square metre, is given by 100(D P D 1 ) where A.6.2 Grammage of aluminium The grammage of the aluminium, expr
48、essed in grams per square metre, is given by 100(D a D 2 ) where A.6.3 Grammage of polyethylene The grammage of the polyethylene, expressed in grams per square metre, is given by 100M s (G p+ G a ) where NOTE 1The thickness of the polyethylene layer in samples taken from sack wall laminate can vary
49、by up to 20% of the mean, depending upon the equipment used in its manufacture. D p is the mass, in grams, of the dish and dried paper(A.5.3); D 1 is the mass, in grams, of the empty dish(A.5.3). D a is the mass, in grams, of the dish and dried aluminium (A.5.3); D 2 is the mass, in grams, of the empty dish(A.5.3). M s is the mass, in grams, of the dried sample(A.4.2); G p is the grammage of the paper (A.6.1); G a is the grammage of the aluminium(A.6.2).BS
