BS 65:1991 pdf free download.Specification for Vitrified clay pipes, fittings and ducts, also flexible mechanical joints for use solely with surface water pipes and fittings.
1. Scope
BS 65 specifies requirements for vitrified clay pipes and fittings with or without sockets, and compatible accessories, for the construction of drainage and sewerage systems, operated as gravity pipelines, or for use as ducts.
Normal and extra chemically resistant pipes and fittings are covered by the standard, when supplied without flexible mechanical joints, for example to meet repair situations or for use with special jointing compounds.
Surface water pipes and fittings are also
covered by the standard, together with ducts. The standard applies to both glazed and unglazed products.
The standard also specifies performance requirements for flexible mechanical joints used with surface watr clay pipes and fittings.
NOTE. The pipes and fittãnGs specified may be sutabIe for use with joints other than flexible mechanical points but suct oents e outs de the sa..pe of this slandct.
The requir•ments specified coier certain dimensions and tolerances, physical and performance characteristics, marking and sampling, and testing and inspection procedures to venfy compliance and to facilitate quality control.
2. References
The titles of the standards pubLications referred to in this standard are listed on the inside back cover.
3. Definitions
For the purposes of this British Standard the following
definitions apply.
3.1 Types of pipes and fittings
3.1.1 Normal. SuitabJe for drainage and sewerage systems, other than where extra chemical resistance is required.
3.1.2 Surface water. Suitable only for the conveyance of surface waler.
3.13 Extra chemically resistant. Suitable for drains and sewers where extra chemical resistance is required.
3.1.4 Ducts. Suitable for the enclosure and protection of underground cables or other services.
3.2 Other definitions
3.2.1 curvature. The angle subtended by the length of a curved fitting at the centre of a circle of nominal radius through the centre-line of the titling.
3.2.2 joint assembly. The adjacent ends of two pipes and the means of joining them.
3.2.3 pipe section. A short leiigth of pipe barrel equal to or greater than 300 mm,
8.3 Chemical resistance. When subjected to the chemical resistance test described in appendix E. the ms loss of any test piece shall not exceed 0.25 %.
NOTE. Normal. surface water and duct fittings should be resistant to attack by che.mcels likely to be found in waste water1 surface water or ground weter,
8.4 Test for extra chemical resistance. When subjected to the test described in appendix F. extra chemically resistant fittings shall comply with the requirements specified in 6.6.1 and 6.6.2.
8.5 Crushing strength. Where bends, junctions, taper pipes or bell mouths are fired in a plant alongside pipes. using the same materials and firing process, the crushing strength of these fittings is deemed to be that of the pipes when tested to 6.2. If pipes are not normally fired alongside these fittings, straight fittings or short lengths of pipes made for test purposes, using the same materials arid firing process as for these fittings, shall be typetested for compliance with the requirements of 6.2.
NOTE. This claus, also applies to fittinqs of stiengths hiqher than those specihed in table 3(a) and 3(b).
Section four. Flexible mechanical joints
9. Performan requirements
9.1 General. This section specifies the performance require. menu for flexible mechanical joints suitable for surface water clay pipes and their fittings.
Surtace water pipe joint assemblies shall satisfy the test requirements of 9,2 to 9.4 at a pressure of 30 kPa. A component shall not be tested in more than one assembly. If it is not practicable to apply precisely the deflection. pressure, load or separation specified, a joint assembly shall be deemed to satisfy the test requirements provided that the levels applied M grmtr than thns spcifiecI
NOTE. Detterent ointinq systems and smiler systems by different manufacturers, while individually complying with the requirements of this standard, may not necessarily be ‘nt•rchangeabl..
9.2 Deflection. One pipe in a joint assembly shall be deflected by the method described in G.2 by the amount specified in table 7 for its relevant nominal size and when so deflected shall withstand the constant internal pressure specified in 91 for 5 mm without visible leakage. Deflection is defined as the distance from the extended longitudinal axis of one pipe to the lonqitudinal axis of the other pipe at its tree end.
9.3 Straight draw. The pipes within a joint assembly shall be separated by 10 mm using the method described in G.3 and when separated shall withstand the constant internal pressure specificd in 9.1 for 5 mm without visible leakage.
13. Marking
13.1 A company trade mark or the name of the manufac• Luret, dnd a means of identifying the date of manufacture shall preferably be impressed before firing, or, if this is not possible, shall be indelibly marked after firing on each pipe and fitting. The marking shall include identification of factory location if the manufacturer has more than one works.
Where, in the production of fabricated units using fired components, the original marking cannot be retained, a marking shall be applied by the same methods as those used to comply with 13.2 to 13.5. showing a company trade mark or the name of the manufacturer and a means of identifying the date of fabrication.
13.2 All pipes and linings shall be clearly and indelibly marked before despatch with the number of this British Standard, i.e. BS 65.
In addition, surface water pipes and tittings shall be marked ‘surface watcr’ or ‘SW’. and extra chemically resistant pipes and fittinqs shall be marked ‘ECR’. Ducts and duct fittings shall be marked ‘Duct’.
13.3 In addition to the above marking, pipes and pipe sections claimed to comply with the requirements of clause 6 for ‘Extra strength’ or ‘Super strength’ classes shall be marked with the words ‘Extra strength’ or ‘Super strength’ as appropriate.
Pipes claimed by the manufacturer to exceed the requirements for super strength pipes or pipe sections shall be marked with the claimed crushing strength and bending moment resistance, e.g.’.. . kN/m .. . kNm’.
13.4 Pipes a,id fittings suitable for use with flexible mechan,.’l joints complying with the requirements specified in section four shall also be marked with the letter ‘J’.
13.5 Flexible mechanical joints supplied as separ ate coñiponents (e.g. ‘sleeves’ but not an integral spigot and socket system) shall be clearly and durably marked with the followng
(a) the trademark or name of the manufacturer; (b) the identification of the factory location if the manufacturer has more thn one works;
(c) the number of BS 65, i.e. ‘BS 65’;  the letters ‘J’ and ‘SW’ for use with surface water pipes;
(e) if the joints are not supplied by the manufacturer of the pipes and fittings with which they are intended to be used, or if the manufacturer stipplies incompatible wstems (see the note to 9.1). the joints shall be clearly and durably marked to identify the pipes or fittings with which they are compatible.