1、BRITISH STANDARD BS 7442-4.3: 1993 ISO 6123-3: 1985 Rubber or plastics covered rollers Part 4: Requirements Section 4.3 Specification for dimensional tolerances UDC 678.06:62-434:621.753.1BS7442-4.3:1993 This British Standard, having been prepared under the directionof the Plastics and Rubber Standa
2、rds Policy Committee, was published underthe authority of the Standards Board and comesintoeffect on 15September1993 BSI 07-1999 The following BSI references relate to the work on this standard: Committee reference PRM/73 Draft for comment 84/37164 DC ISBN 0 580 22504 6 Committees responsible for th
3、is British Standard The preparation of this British Standard was entrusted by the Plastics and Rubber Standards Policy Committee (PRM/-) to Technical Committee PRM/73, upon which the following bodies were represented: British Rubber Manufacturers Association Ltd. British Structural Bearings Manufact
4、urers Association Building Employers Confederation Department of Transport Institution of Medical Laboratory Sciences Institution of Structural Engineers Malaysian Rubber Producers Research Association Ministry of Defence Royal Society of Chemistry Amendments issued since publication Amd. No. Date C
5、ommentsBS7442-4.3:1993 BSI 07-1999 i Contents Page Committees responsible Inside front cover National foreword ii 0 Introduction 1 1 Scope and field of application 1 2 References 1 3 Definitions 1 4 Test methods 1 5 Classes of dimensional tolerances 1 6 Dimensional tolerances on roller diameter 2 7
6、Dimensional tolerances on cover length 2 8 Run-out tolerances 3 9 Cylindricity or crown tolerances 4 Figure 1 Run-out tolerances 4 Figure 2 Cylindricity tolerances 5 Figure 3 Crown tolerances 6 Table 1 2 Table 2 3 Table 3 3 Table 4 4 Table 5 5 Table 6 6 List of references Inside back coverBS7442-4.3
7、:1993 ii BSI 07-1999 National foreword This British Standard has been prepared under the direction of the Plastics and Rubber Standards Policy Committee. It is identical with ISO6123-3:1985 Rubber- or plastics-covered rollers Specifications Part 3: Dimensional tolerances, published by the Internatio
8、nal Organization for Standardization (ISO). The Technical Committee has reviewed the provisions of ISO1101:1983, to which normative reference is made in the text, and has decided that they are acceptable for use in conjunction with this standard. The actual tolerances on roller dimensions which are
9、acceptable, depend upon the particular end-use to which the roller will be put. In this regard attention is drawn to the statements in clause5. Additional information. Clause4 refers to a standard temperature of 23 C or27 C. In the UK the standard (laboratory) temperature is 23 2 C (see4.1). Some of
10、 the terms listed in3.4 are defined in Part 1 of BS7442. NOTEInTable 3, “class O” should be “class Q” (see clause5). 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
11、British Standard does not of itself confer immunity from legal obligations. Cross-references International standard Corresponding British Standard ISO 471:1983 BS 903 Physical testing of rubber Part A35:1985 Temperatures, humidities and times for conditioning and testing of test pieces (Identical) I
12、SO/TR 7621:1982 BS 7442 Rubber or plastics covered rollers Part 2:1991 Recommendations for technical information to be provided by the purchaser (Identical) Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, pages1 to 6, an inside back cover and a back cov
13、er. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on theinside front cover.ISO6123-3:1985(E) BSI 07-1999 1 0 Introduction Covered rollers are cylindrical cores, generally of metal, with a cover of rubber or
14、 plastics for a particular use. They are manufactured in a wide variety of sizes and hardness grades depending on the intended use. ISO6123 consists of the following parts: Part 1: Requirements for hardness; Part 2: Surface characteristics; Part 3: Dimensional tolerances. 1 Scope and field of applic
15、ation This part of ISO6123 specifies classes of dimensional tolerances for rubber- or plastics-covered rollers and tests methods for the measurement of dimensions. 2 References ISO 471, Rubber Standard temperatures, humidities and times for the conditioning and testing of test pieces. ISO 1101, Tech
16、nical drawings Geometrical tolerancing Tolerances of form, orientation, location and run-out Generalities, definitions, symbols, indications on drawings. ISO/TR 7621, Rubber or plastics covered rollers Enquiries and orders Recommendations for technical information to be supplied by the purchaser. 3
17、Definitions 3.1 crown (of a rubber- or plastics-covered roller) the difference between the diameter in the centre of the roller and the diameter at or near the edges of the roller the profiles and dimensions of crown are referred to and measured on the measured crown face (MCF) for definition of the
18、 profile tolerance of the MCF seeISO1101. sub-clause 14.5 NOTE 1Normally the crown is positive. If the covered roller is larger in diameter at the ends than in the centre it is called an inverse crown. NOTE 2Unless otherwise specified, a crown is symmetrical above the centre-line of the roller which
19、 is the centre-line of the MCF. NOTE 3Two types of crown are usual: a) taper crown where there is a linear change in diameter with distance along the roller face from around the centre-line; b) crown where the variation in diameter is non-linear, for example cosine crown. NOTE 4Normally the MCF star
20、ts 50mm in from the ends of the roller cover or from the ends of any edge relief such as taper, chamfer or dub. NOTE 5Conventionally the MCF is divided into ten equally spaced parts from end to centre, i.e. total 20 parts. The crown shape is described by ten readings from and to centre, i.e. total 2
21、1 diametral readings. 3.2 cylindricity tolerance see ISO1101, sub-clause 14.4 3.3 run-out tolerance see ISO1101, sub-clause 14.13.1 3.4 Other terms For cover face length, cover thickness, cover outside diameter (finished diameter), core outside diameter, taper, chamfer, and dub, see ISO/TR7621, Figu
22、re 1. 4 Test methods 4.1 Test temperature Measurement shall be carried out at a standard temperature (23 2 Cor27 2 C) in accordance with ISO471, when and where possible. The covered roller shall be brought to the test temperature prior to measuring to ensure temperature equilibrium. As dimensions ca
23、n be affected by temperature, the same test temperature shall be used throughout any one test or series of tests intended to be comparable. If this condition cannot be met, it is necessary to consider the influence of temperature on the used compound in order to compare the results correctly. The me
24、asuring temperature shall be recorded. 4.2 Test instruments The dimensions of the rubber- or plastics-covered rollers, the deviation from cylindricity and the run-out shall be measured by suitable instruments. Calipers and dial-gauges shall be used with plungers or rolls which shall exert a pressure
25、 of225kPa for rubber or plastics of hardness equal to or greater than 35 IRHD or of 102kPa for hardness less than 35 IRHD. NOTEThe following instruments can be taken as suitable: a) tape measures (with or without vernier), sliding calipers or micrometer calipers for diameters and lengths; b) sliding
26、 calipers, micrometer calipers or roll calipers with dial indicator gauge for crown and cylindricity; c) dial indicator gauges for run-out. 5 Classes of dimensional tolerances This part of ISO6123 specifies six classes of tolerances as follows: XXP Very high precision XP High precision P Precision H
27、 High qualityISO6123-3:1985(E) 2 BSI 07-1999 The class specified depends on the type of roller and the requirements of the application. Within a single roller a different class may apply to each of the dimensions in clauses6 to9. It should be noted (see clauses6, 8 and9) that the closest tolerances
28、are not applicable to all hardnesses of the cover. In general, soft covers need greater tolerances than harder ones. Class N tolerances are to be used when the roller specification does not indicate a required tolerance class. NOTENominal dimensions inTable 1 toTable 6 are based on the R 5 series of
29、 preferred numbers. 6 Dimensional tolerances on roller diameter 6.1 General The permissible tolerance depends on the length and rigidity of the roller and the hardness of the cover. The class shall be taken fromTable 1 or Table 2. When the thickness of the cover is specified the tolerance shall be b
30、ased on the diameter of the finished roller being the core diameter plus two times the cover thickness. A change of tolerances in either direction is permissible, so that, for example, the permissible tolerance of 0,4 may also be stated asor or etc. 6.2 Roller length to diameter ratio up to 15 Diame
31、ter tolerances for rollers of sufficient rigidity and with a length of cover of up to 15 times the core diameter are specified inTable 1. 6.3 Roller length to diameter ratio between 15 and 25 Diameter tolerances for rollers of sufficient rigidity and with a length of cover above 15 and up to25times
32、the core diameter are specified inTable 2. 6.4 Other rollers Diameter tolerances for rollers of insufficient rigidity or with a length of cover above 25 times the core diameter shall be agreed between the interested parties. 7 Dimensional tolerances on cover length The permissible cover length toler
33、ance shall be taken from the classes inTable 3. Class XP (high precision) applies to a roller with uncovered ends where the cover face terminates plane with the core end. The tolerance is based not on the nominal but on the real length of the core. A change of tolerances in either direction is permi
34、ssible, so that, for example, the permissible tolerance of 0,8 may also be stated asor or etc. Table 1 Q Quality N Non-critical + 0,2 0,6 + 0,8 0 0 0,8 + 0,4 1,2 + 1,6 0 0 1,6 Hardness Class IRHD Shore A Pusey and Jones 120 H Q N 50 to 70 120 to 70 P H Q N 70 to 40 to 63 m 0,05 0,07 0,15 0,20 0,3 0,
35、6 63 to 100 0,06 0,09 0,15 0,25 0,4 0,7 100 to 160 0,07 0,11 0,20 0,30 0,5 0,9 160 to 250 0,08 0,14 0,25 0,40 0,6 1,1 250 to 400 0,11 0,18 0,30 0,50 0,8 1,4 400 to 630 0,14 0,23 0,40 0,65 1,1 1,8 630 a 0,50 0,75 1,25 2,0 3,0 a XXP tolerances for diameters above nominal dimension 630 shall be agreed
36、between the interested parties.ISO6123-3:1985(E) BSI 07-1999 3 Table 2 Table 3 8 Run-out tolerances The permissible tolerances depend on the hardness of the cover and the diameter of the roller. When the thickness of the cover is specified the tolerances shall be based on the diameter of the finishe
37、d roller being the core diameter plus twice the cover thickness. Run-out tolerances (seeFigure 1) for rollers of sufficient rigidity are specified inTable 4. Tolerances for rollers of insufficient rigidity shall be agreed between the interested parties. NOTEFor run-out tolerance testing, the roller
38、circumferential speed should not exceed 30m/min. Hardness Class IRHD Shore A Pusey and Jones 120 H Q N 50 to 70 120 to 70 P H Q N 70 to 40 to 63 0,07 0,15 0,20 0,3 0,6 1,0 63 to 100 0,09 0,15 0,25 0,4 0,7 1,2 100 to 160 0,11 0,20 0,30 0,5 0,9 1,5 160 to 250 0,14 0,25 0,40 0,6 1,1 1,8 250 to 400 0,18
39、 0,30 0,50 0,8 1,4 2,3 400 to 630 0,23 0,40 0,65 1,1 1,8 3 630 0,50 0,75 1,25 2,0 3,0 5 Values in millimetres Nominal cover face length Class XP O N Length tolerance 250 0,2 0,5 1,0 250 to 400 0,2 0,8 1,5 400 to 630 0,2 1,0 2,0 630 to 1000 0,2 1,0 2,5 1000 to 1600 0,2 1,5 3,0 1600 to 2500 0,2 1,8 3,
40、5 2500 0,2 0,08% 0,15%ISO6123-3:1985(E) 4 BSI 07-1999 Table 4 9 Cylindricity or crown tolerances 9.1 Cylindricity tolerances The permissible tolerances depend on the hardness of the cover and the diameter of the roller When the thickness of the cover is specified, the tolerances shall be based on th
41、e diameter of the finished roller being the core diameter plus twice the cover thickness. Cylindricity tolerances (seeFigure 2) for rollers of sufficient rigidity are specified inTable 5. Tolerances for rollers of insufficient rigidity shall be agreed between the interested parties. Figure 1 Run-out
42、 tolerances Hardness Class IRHD Shore A Pusey and Jones 120 H Q N 50 to 70 120 to 70 P H Q N 70 to 40 to 63 0,02 0,03 0,06 0,10 0,18 63 to 100 0,03 0,04 0,08 0,13 0,20 100 to 160 0,03 0,05 0,10 0,17 0,25 160 to k250 0,03 0,06 0,12 0,20 0,30 250 to 400 0,04 0,07 0,14 0,23 0,35 400 to 630 0,04 0,08 0,
43、18 0,30 0,45 630 0,05 0,10 0,25 0,35 0,55ISO6123-3:1985(E) BSI 07-1999 5 Table 5 9.2 Crown tolerances The permissible crown tolerance (seeFigure 3) shall be taken from classes inTable 6. Figure 2 Cylindricity tolerances Hardness Class IRHD Shore A Pusey and Jones 120 H Q 50 to 70 120 to 70 P H Q 70
44、to 40 to 63 0,02 0,03 0,06 0,10 0,19 63 to 100 0,03 0,04 0,08 0,13 0,20 100 to 160 0,03 0,05 0,10 0,17 0,25 160 to 250 0,03 0,06 0,12 0,20 0,30 250 to 400 0,04 0,07 0,14 0,23 0,35 400 to 630 0,04 0,08 0,18 0,30 0,45 630 0,05 0,10 0,25 0,35 0,55ISO6123-3:1985(E) 6 BSI 07-1999 Table 6 Figure 3 Crown t
45、olerances Values in millimetres Nominal crown Class XP P Crown profile tolerance, s 0,10 0,04 0,06 0,10 to 0,16 0,05 0,08 0,16 to 0,25 0,06 0,10 0,25 to 0,40 0,08 0,12 0,40 to 0,63 0,10 0,16 0,63 to 1,00 0,12 0,20 1,00 to 1,60 0,16 0,30 1,60 to 2,50 0,25 0,40 2,50 to 4,00 0,40 0,60 400 10% a a P tol
46、erances for crowns above nominal dimension 4,00 shall be agreed between the interested parties and expressed as a percentage.BS7442-4.3:1993 BSI 07-1999 List of references See national foreword.BS 7442-4.3: 1993 ISO 6123-3: 1985 BSI 389 Chiswick High Road London W4 4AL BSIBritishStandardsInstitution
47、 BSI is the independent national body responsible for preparing BritishStandards. It presents the UK view on standards in Europe and at the international level. It is incorporated by Royal Charter. Revisions BritishStandards are updated by amendment or revision. Users of BritishStandards should make
48、 sure that they possess the latest amendments or editions. It is the constant aim of BSI to improve the quality of our products and services. We would be grateful if anyone finding an inaccuracy or ambiguity while using this BritishStandard would inform the Secretary of the technical committee responsible, the identity of which can be found on the inside front cover. Tel:02089969000. Fax:02089967400. BSI offers members an individual updating service called PLUS which ensures that su
