BS 2775-1987 Specification for rubber stoppers and tubing for general laboratory use《普通实验室用橡皮塞和橡皮管规范》.pdf
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1、BRITISH STANDARD BS 2775:1987 Specification for Rubber stoppers and tubing for general laboratory use UDC 542.25 + 542.263.3:678BS2775:1987 This British Standard, having been prepared under the direction of the Rubber Standards Committee was published under the authority of the Board of BSI and come
2、s into effect on 31 December 1987 BSI 07-1999 First published October 1956 First revision January 1967 Second revision The following BSI references relate to the work on this standard: Committee reference RUM/35 Draft for comment 85/37794 DC ISBN 0 580 16138 2 Committees responsible for this British
3、 Standard The preparation of this British Standard was entrusted by the Rubber Standards Committee (RUM/-) to Technical Committee RUM/35, upon which the following bodies were represented: British Rubber Manufacturers Association British Structural Bearings Manufacturers Association Building Employer
4、s Confederation Concrete Society Department of the Environment (Building Research Establishment, Princes Risborough Laboratory) Department of Transport (Highways) Flexible Roofing Association Institute of Medical Laboratory Sciences Institution of Structural Engineers Malaysian Rubber Producers Rese
5、arch Association Ministry of Defence Royal Society of Chemistry Amendments issued since publication Amd. No. Date of issue CommentsBS2775:1987 BSI 07-1999 i Contents Page Committees responsible Inside front cover Foreword ii 1 Scope 1 2 Definitions 1 3 Physical requirements 1 4 Dimensions 1 5 Colour
6、 5 6 Marking of packaging 5 Appendix A Guide to the properties of each type of polymer 6 Figure 1 Dimensions for stoppers 2 Figure 2 Location of two holes in a stopper 2 Table 1 Physical property requirements 3 Table 2 Change in properties after accelerated ageing 3 Table 3 Dimensions of stoppers 4
7、Table 4 Dimensions of normal wall tubing 4 Table 5 Dimensions of heavy wall tubing 5 Publications referred to Inside back coverBS2775:1987 ii BSI 07-1999 Foreword This British Standard has been prepared under the direction of the Rubber Standards Committee and is a revision of BS2775:1967 which is w
8、ithdrawn. The materials specified in this British Standard are intended for general laboratory use and compounds in which specific properties have been enhanced for special applications are not included. Other British Standards pertaining to stoppers and/or tubing for particular applications are BS2
9、050, BS2463 and BS3212. The types of tubing specified in this British Standard are intended for use at relatively low gauge pressures, below1 bar 1) , or under vacuum. Use of the term “pressure tubing” for the heavy wall tubing specified in this British Standard is deprecated. Reinforced hoses compl
10、ying with BS5118, BS5119, BS5120, BS5121 or BS5122 are suitable for use under pressure. Attention is drawn to the fact that when elastomeric tubing is used in a vacuum system at pressures below 1 mm of mercury, the tubing tends to emit vapours which raise the pressures as if there were a leak in the
11、 system. A guide to some of the properties of the various types of polymer is included as Appendix A. For further information, such as suitability for contact with particular fluids and chemicals, the supplier or manufacturer should be consulted. The task of inserting glass tubing into rubber stoppe
12、rs has been the cause of a large number of accidents in the laboratory. Attention is therefore drawn to “Introduction to safety in the chemical laboratory” by N T Freeman and JWhitehead, published by Academic Press. A British Standard does not purport to include all the necessary provisions of a con
13、tract. Users of British Standards are responsible for their correct 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 and ii, pages1to 6, an inside back cov
14、er and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover. 1) 1 bar 10 5Pa = 10 5N/m 2BS2775:1987 BSI 07-1999 1 1 Scope This British Standard specifies requirements for ru
15、bber used for stoppers and tubing intended for general laboratory use, and the dimensions of the stoppers and tubing. It is applicable to stoppers and tubing made from natural rubber and synthetic isoprene rubber, styrene-butadiene rubbers, chloroprene rubbers, ethylene-propylene-diene rubbers (EPDM
16、), silicone rubbers and fluorocarbon rubbers. NOTEThe titles of the publications referred to in this standard are listed on the inside back cover. 2 Definitions For the purposes of this British Standard, the definitions given in BS3558 apply. 3 Physical requirements 3.1 General The rubber shall comp
17、ly with the appropriate requirements given in Table 1. 3.2 Appearance and finish When examined visually, all outer surfaces of the finished product shall be homogeneous and free from porosity and grit. NOTEIn the interests of safety, manufacturers should ensure that the interior of rubber stoppers a
18、nd tubing is free from grit and other extraneous matter, porosity, voids, inclusions and other similar defects. 3.3 Change in properties after accelerated ageing The test pieces shall be aged in an air oven in accordance with BS903-A19 for168 h for natural rubber and synthetic isoprene rubber and st
19、yrene-butadiene rubbers, and for70h for the other polymers, at the appropriate temperature as follows: a) natural rubber and synthetic isoprene rubber and styrene-butadiene rubbers at70 C; b) chloroprene rubbers and EPDM at100 C; c) silicone rubbers at200 C; d) fluorocarbon rubbers at250 C. After ag
20、eing, the rubber shall comply with the appropriate requirements given in Table 2. 3.4 Test pieces The test pieces shall be taken either from the product, or from a moulded test sheet prepared from the same material as the product and vulcanized for an appropriate time and at an appropriate temperatu
21、re to achieve the same state of cure. NOTE 1In most instances it is not possible to obtain the required test pieces from the actual product and so the test pieces are taken from a moulded test sheet. NOTE 2An example of a suitable test sheet is specified in BS1674 and is a sheet approximately250 mm
22、square with a section along one side35mm to50mm wide and6.30 0.15mm thick, while the thickness of the remainder of the sheet is2.00 0.15 mm. Part of the6.30mm section may be moulded in the form of cylindrical buttons conforming to the requirements for type 1 test pieces specified in BS903-A6, for us
23、e in the determination of compression set. No additional vulcanization should be applied to the thicker section (or buttons) of the sheet. 4 Dimensions 4.1 Stoppers 4.1.1 General. The sizes of a stopper shall be designated by the nominal bottom diameter (dimension A in Figure 1). The diameters and l
24、ength of stoppers shall be as given in Table 3. NOTEThe size of stopper selected for use should provide a seal at a point between30% and60% along its length from the bottom (see Figure 1). 4.1.2 Pre-bored stoppers. Holes in pre-bored stoppers shall be parallel with the axis of the stopper. For sizes
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- BS27751987SPECIFICATIONFORRUBBERSTOPPERSANDTUBINGFORGENERALLABORATORYUSE 普通 实验室 橡皮 橡皮管 规范 PDF

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