BS ISO 12230:2012 pdf download
BS ISO 12230:2012 pdf download.Polybutene-1 (PB-1) pipes Effect of time and temperature on the expected strength.
BS ISO 12230 specifies minimum values for the expected strength as a function of time and
temperature in the form of reference lines and tabulated data, for use in calculations on pipes made of
— polybutene-1 homopolymer (PB-H), and
— polybutene-1 random copolyrner (P8-R).
For the sake of simplicity the designation polybutene and the abbi’eviabon PB are used throughout
2 Not-mative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies For undated references the latest edition of the referenced document (including any amendments) appbes
ISO 1167-i, Themioplastics pipes, fittings and assemblies for the conveyance of fluids — Determination of the resistance to Internal pressure – Part 1: General method
ISO 1167-2. Thermoplastics pipes, fillings and assemblies for the conveyance of fluids — Determination of the resistance to internal pressure – Part 2: Preparation of pipe test pieces
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
reference line
minimum long-term hydrostatic strength to be expected Irom a particular polymer
NOTE I Reference lines are not to be oonsãdered as charadaflsbc ala speciltc Wade ci material from a specific suppler.
NOTE 2 The lines are dezcnbod by a mathematical eQuation which pemi4s interpolation and extrapolation in an unambiguous way at various temperatwes.
NOTE 3 The reference Iies for polybutene (PB) have bean agreed upon by a group of experts after considering experimental data, and have been accepted by the relevant technicai commiltees in ISO.
3.2
polybutene-1 homopolymer
PB-H
compomd prepared by polymnenzation of no less than 95 % butane-i by weight
3.3
polybutene- 1 random copolymer
PB-R
coaound prepared by polymenzabon of no less than 85% butane-i and no less than 95% of total olefins by weight
With a life of one year at 110 C, these values are therefore the number of years the pipes would be expected to last at each of the temperatures g.ven.
For temperatures up to and including 50 C, an extrapolation factor k of 100 Is acceptable
5.3 GraphIcal representation
Figures 1 and 2 contain the reference lines for PB-H and PB-R. respectively, corresponding to the vakies of the parameters given in this clause, which shall be used for demonstrating conformance to this specification In accordance with Annex A.
The broken lines represent the extrapolation of the reference lines, applicable when longer failure times are obtained at 110 C, extrapolation being permitted up to the limits even by the extrapolation factors in Table 1.
5.4 Tabulated values
The calculated hoop strength values to be used for various temperatures and times are given in Table 2 for PB-H and Table 3 for PB-R and do not include design factors.
The times at 80 C, 90 C and 95 C not in brackets in the time column in Table 2 for PB-H and Table 3 for PB-R are based on a lifetime of one year at 110 C. Proof of a leriger iIetirne at 110 C allows a corresponding extension of the times at lower temperatures. Such values are given in brackets in Tables 2 and 3.
In accordance with ISO 9080 failure points at 20 °C up to 1,000 h may be neglected.
If there are dfcultis obtaining filures in some of the time intervals any running data point above the reference line can be accepted as showing conformance to the reference line.
For tests lasting longer than 8 760 h without failure, the actual test time can be considered as the failure time, provided it is on or above the reference line.
Testing shall be carried out in accordance with ISO 1167-1 and ISO 1167-2.
Conformance to the reference lines shall be demonstrated by potting the individual experimental results on the graph. At least 97.5 % of them shall lie on or above the reference lines.
