1、International Standard 6448 0 0 4 a! lNTERNATlONAL ORGANlZATlON FOR STANOARDIZATlON.MEX.flYHAPOHAR OPl-AHbl3AUWR OCTAHAPTbi3AbiM*ORGANlSATiON INTERNATIONALE DE NORMALISATION Rubber seals - Joint rings -used for petroleum product supply pipes and fittings - Specification for material Caoutchouc - Gar
2、nitures dVtanchM& pour joints de canalisations de produits p&roliers - Spkifications des matkriaux First edition - 1985-04-15 UDC 621343.44 Ref. No. IS0 6448-1985 (E) Descriptors : pipe joints, rubber, rubber products, sealing rings, specifications, tests, quality assurance. Price based on 4 pages C
3、opyright International Organization for Standardization Provided by IHS under license with ISONot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Foreword IS0 (the International Organization for Standardization) is a worldwide federation of national standards bodies (I
4、S0 member bodies). The work of preparing International Standards is normally carried out through IS0 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 organizations, gov
5、ern- mental and non-governmental, in liaison with ISO, also take part in the work. Draft International Standards adopted by the technical committees are circulated to the member bodies for approval before their acceptance as International Standards by the IS0 Council. They are approved in accordance
6、 with IS0 procedures requiring at least 75 % approval by the member bodies voting. International Standard IS0 6448 was prepared by Technical Committee ISO/TC 45, Rubber and rubber products. 0 international Organization for Standardization, 1985 0 Printed in Switzerland Copyright International Organi
7、zation for Standardization Provided by IHS under license with ISONot for ResaleNo reproduction or networking permitted without license from IHS-,-,-INTERNATIONAL STANDARD IS0 6448-1985 (E) Rubber seals - Joint rings used for petroleum product supply pipes and fittings - Specification for material 1
8、Scope and field of application This International Standard specifies requirements for ma- terials used in vulcanized solid rubber sealing rings for petroleum product supply pipe and fittings. It does not apply to petroleum products having an aromatic content higher than 30 % (VI VI nor to liquids po
9、lluted by traces of petroleum products (e.g. pipes for waste water). Some general requirements for the finished joint rings are also given. If there are other requirements for the performance of the finished joint rings, particularly functional tests for the actual sealing system and related pipelin
10、e materials, they shall be specified additionally in national standards. This International Standard is applicable to joint rings for all pipeline materials including iron, steel, copper, plastics. In the case of composite sealing rings, depending on their design and after agreement between the manu
11、facturer and the user, the materials used for any rubber parts not coming into contact with petroleum products shall not have to comply with the requirements of 5.7 and 5.8 of this International Standard. Joint rings made from cellular rubber materials or with enclosed voids as part of their design
12、and joint rings with requirements of resistance to flame to thermal stress are not included in this International Stand 2 References IS0 37, Rubber, vulcanized - Determination of tensile stress- strain properties. IS0 48, Vulcanized rubbers - Determination of hardness (hardness between 30 and 85 IRH
13、D). IS0 188, Rubber, vulcanized - Accelerated ageing or heat- resistance tests. IS0 471, Rubber - Standard temperatures, humidities and times for the conditioning and testing of test pieces. IS0 812, Rubber, vulcanized - Determination of brittleness temperature. 1) IS0 815, Rubber, vulcanized - Dete
14、rmination of compression set at normal and at high temperatures.21 IS0 1817, Rubber, vulcanized - Determination of the effect of liquids. IS0 2230, Vulcanized rubber - Guide to storage. IS0 3302, Rubber - Dimensional tolerances of solid moulded and extruded products. IS0 3384, Rubber, vulcanized - D
15、etermination of stress re- laxation in compression at normal and at elevated tem- pera tures. IS0 4551, Rubber - Preparation of test pieces. 3 Classification Five classes of material are specified (see tables 1 and 2). These correspond to preferred nominal hardnesses of 50, 60, 70, 80 and 88 IRHD. I
16、f required, an intermediate nominal hardness dif- ferent from those indicated in the table may be used. 4 Materials 4.1 The materials shall be free of any substance which may have a deleterious effect on the fluid to be conveyed, or on the life of the sealing ring, or on the pipe and fittings. 4.2 T
17、he requirements for materials of preferred nominal hard- ness 80 or 88 IRHD shall apply only when the material is directly participating in the sealing function. 1) At present at the stage of draft. (Revision of ISO/R 812-1968.) 2) At present at the stage of draft. (Revision of IS0 815-1972.) 1 Copy
18、right International Organization for Standardization Provided by IHS under license with ISONot for ResaleNo reproduction or networking permitted without license from IHS-,-,-IS0 6448-1985 (El 5 General test requirements for material 5.1 Test pieces Unless otherwise specified, the tests shall be carr
19、ied out at standard laboratory temperature in accordance with IS0 471. Test pieces shall be cut from the finished product in accor- dance with IS0 4661 and the other corresponding International Standards. If satisfactory test pieces cannot be prepared in accordance with the appropriate test method,
20、they shall be taken from test slabs or sheets of suitable dimensions made from the same batch of the rubber mix used to make the rings, and vulcanized under conditions which are comparable to those used in production. 5.2 Hardness When determined by the “micro-test” method specified in IS0 48, the h
21、ardness shall comply with the requirements given in table 1. If the dimensions of the ring allow, the “normal test”method specified in IS0 48 may be used, provided the “micro-test” method is used for reference purposes. For the same ring, or along the greatest length of an extruded profile cut to ma
22、ke a ring, hardness values shall not vary more than 4 IRHD from the low to the high readings noted. Each value shall be within the specified tolerances. NOTE - For the purpose of this International Standard, which requires hardness measurements up to 91 IRHD, the micro-test method described in IS0 4
23、9 is considered satisfactory. 5.3 Tensile strength and elongation at break The tensile strength and elongation at break shall be deter- mined by the method described in IS0 37, using type 2 dumb- bell shaped test pieces. Other types of test pieces may be used if an agreement is reached upon the rela
24、tionship between the values obtained with type 2 dumb-bell shaped test pieces and those obtained on the proposed test pieces. The elongation at break shall comply with the requirements given in table 1. The tensile strength shall comply with the requirements given in table 1 and shall be used for qu
25、ality control purposes. 5.4 Compression set When determined by the method described in IS0 815 using the small test piece, the compression set shall comply with the requirements given in table 1. When possible, test pieces for compression set shall be cut in the direction of compression of the ring
26、in service. 5.5 Accelerated ageing in air When the test pieces required by 5.2 for the determination of hardness and by 5.3 for the determination of tensile strength and elongation at break are aged in air at 70 OC for 7 days by the oven method specified in IS0 188, the changes in hard- ness, tensil
27、e strength and elongation at break shall comply with the requirements given in table 1. 5.6 Stress relaxation in compression When determined by method A specified in IS0 3384 using the small test piece and after applying mechanical and thermal con- ditioning, the stress relaxation in compression aft
28、er 7 days at standard laboratory temperature shall comply with the re- quirements given in table 1. The test piece shall be cut as far as possible in the direction of compression of the ring. 5.7 Liquid B immersion 5.7.1 Volume change When determined by the method specified in IS0 1817, the volume c
29、hange after an immersion of 7 days at standard laboratory temperature in liquid B shall comply with the re- quirements given in table 1. For approval tests only, the volume change when immersed in liquid B shall not exceed the specified maximum value given in table 1 at any time throughout the durat
30、ion of the 7 days im- mersion. 5.7.2 Hardness change When the test pieces described in 5.2 are tested in accordance with IS0 1817, the hardness change after an immersion of 7 days at standard laboratory temperature in liquid B shall com- ply with the requirements given in table 1. 5.6 Oil No. 3 imme
31、rsion 5.8.1 Volume change When determined by the method specified in IS0 1817, the volume change after an immersion of 7 days at 70 X in Oil No. 3 shall comply with the requirements given in table I. 5.8.2 Hardness change When the test pieces described in 5.2 are tested in accordance with IS0 1817,
32、the hardness change after an immersion of 7 days at 70 OC in Oil No. 3 shall comply with the requirements given in table 1. 6 Optional test requirements for material Each of the following tests is optional and shall be carried out only if expressly specified by the purchaser. Copyright International
33、 Organization for Standardization Provided by IHS under license with ISONot for ResaleNo reproduction or networking permitted without license from IHS-,-,-IS0 8448-1985 (E) Table 1 - General requirements Property Unit 50 Requirements 60 70 80 aa Preferred nominal hardness IRHD 50 60 70 80 aa Range o
34、f nominal hardness IRHD 46 to 55 56 to 65 66 to 75 76 to 64 a5 t0 91 Permissible tolerance on specified nominal hardness* IRHD +5 +5 f5 f4 +3 Tensile strength, min. MPa 9 10 10 10 10 Elongation at break, min. % 400 300 200 150x* 100” Compression set after 70 h at standard laboratory temperature, max
35、. % 10 10 10 15* 15* after 22 h at 70 X, max. % 20 20 20 20* 20* Ageing - change from unaged values after 7 days in air at 70 OC hardness, max. IRHD f6 f6 rt6 +6 f6 tensile strength loss, max. % - 15 - 15 - 15 - 15 - 15 elongation at break, max. % -25to +10 -25to +10 -25to +10 -3oto +10 -40to +10 St
36、ress relaxation in compression, max. after 7 days at standard laboratory temperature* % 15 15 15 15* 15* Liquid B immersion, after 7 days at standard labora- tory temperature volume change, max. % +30 + 30 + 30 + 30 + 30 hardness change, max. IRHD - 16 - 15 - 15 - 14 - 12 Oil No. 3 immersion after 7
37、 days at 70 “C volume change, max. % -1 to +10 - 1 to + 10 - 1 to + 10 - 1 to + 10 - 1 to + 10 hardness change, max. IRHD -6 -6 -6 -6 -6 l In specific cases and after an agreement between manufacturer and user, the tolerance on hardness may be fixed at + 3 IRHD. l * Requirements for material of nomi
38、nal hardness 80 or 88 IRHD shall be applied only when this material participates directly in the sealing function, l * It is recognized that values lower than the ones shown can be obtained. The intention is to reduce the limits once experience has been gathered. Table 2 - Optional requirements Prop
39、erty Stress relaxation in compression, max.* after 90 days at standard laboratory temperature Low temperature brittleness - temperature of test: - 15 OC, - 25 OC or - 40 YZ depending on the condi- tions of service or transportation of the joint rings Unit % 50 22 Requirements 60 70 a0 a6 22 22 22* z
40、* No test pieces shall break l It is recognized that values lower than the ones shown can be obtained. The intention is to reduce the limits once experience has been gathered. l * The requirement only applies when this material participates directly in the sealing function. 3 Copyright International
41、 Organization for Standardization Provided by IHS under license with ISONot for ResaleNo reproduction or networking permitted without license from IHS-,-,-IS0 fX48-198% (El 6.1 Stress relaxation in compression When determined by method A specified in IS0 3394, and after applying mechanical and therm
42、al conditioning, the stress relaxation in compression after 90 days at standard laboratory temperature shall comply with the requirements given in table 2. The test piece shall be cut as far as possible in the direction of compression of the ring. When this test is required, it shall be only a type
43、approval test. 6.2 Low temperature brittleness When tested by the method specified in IS0 812, using type A test pieces, at - 15 VI, -25 OC or -40 OC, the results shall comply with the requirements given in table 2. The test temperature shall be specified by the user as a function of the service con
44、ditions of the joint seal, the conditions of transportation or the temperature of installation. 7 Quality control of material 7.1 Having regard to the hazards associated with the transportation of flammable and explosive fluids, attention is particularly drawn to the need for stringent quality contr
45、ol pro- cedure. 7.2 It is the responsibility of the manufacturer to carry out control tests to confirm that the material for the rings complies with the appropriate requirements of this International Stan- dard. Records of these control tests shall be available to the pur- chaser from the manufactur
46、er of the rings upon request. 8 General requirwrwnts for finished joint rings 6.1 Workmanship 8.1.1 Workmanship shall be in accordance with good com- mercial practice. 8.1.2 The rings shall be free from porosity and shall not have surface defects or irregularities which could affect their func- tion
47、. Flash (sprue) shall be kept to a reasonable minimum. 6.2 Dimensions and tolerances Dimensions and tolerances shall be the subject of agreement between the interested parties. Tolerances shall be chosen fom the appropriate classes in IS0 3302. 8.3 Storage and handling of rings At all stages between
48、 manufacture and use, the rings shall be stored in accordance with the recommendations of IS0 2230. The attention of users is drawn to the need to avoid cracking during storage and handling. If it is considered that risks of cracking exist, additional tests, appropriate to the situation involved, sh
49、all be specified. 8.4 Marking Marking shall allow the identification of the manufacturer and also the use of the ring as a function of the conveyed fluid. 6.5 Quality assurance 8.51 Having regard to the hazards associated with the transportation of flammable and explosive fluids, attention is particularly drawn to the need for stringent quality assurance procedure. 8.5.2 Procedures for quality assurance shall be agreed be- tween the interested parties to validate complianc
