AS NZS 4766 pdf download

AS NZS 4766 pdf download.Rotationally moulded buried, partially buried and non-buried storage tanks for water and chemicals
1.1  Scope
This Standard specifies requirements for the design and manufacture of storage tanks that are rotationally moulded in one‑piece single or multi‑layer seamless construction. This Standard applies to tanks for non‑buried installation capable of containing water, liquids used in food and beverage manufacture, waste oil treatment, fat, oil and grease, diesel and liquid chemicals at atmospheric pressure. This Standard also applies to tanks for buried and partially‑buried installation capable of containing water, liquids used in food and beverage manufacture, waste oil treatment, fat, oil and grease at atmospheric pressure. Methods for demonstrating conformance to this Standard are specified in Appendix A.
1.4  Terms and definitions
For the purpose of this document, the following terms and definitions apply. 1.4.1 multi-layer construction consisting of more than one layer of material 1.4.2 polymer “compound” hot melt mixed blend of virgin polymer or polymers, additives and pigments 1.4.3 polymer “base resin” unpigmented virgin polymer in UV stabilized or non-UV stabilized form 1.4.4 qualified professional engineer engineer who has a relevant degree and is experienced in the design of structural products and applications utilizing polymer plastic materials and computerized finite element analysis (FEA) programs, and has Certified Practicing Engineer (CPEng) status with either the Institution of Engineers, Australia or Engineering NZ or an equivalent registration with a similarly recognized professional body Note 1 to entry: For partially buried and buried tanks, appropriate experience in the field of geotechnical engineering is necessary, or consultation with an appropriately qualified geotechnical engineer should be undertaken. 1.4.5 rated material service temperature temperature at which laboratory tests were undertaken in order to determine long and short term characteristics of the polymer material 1.4.6 reduction factor ϕ de‑rating value that takes into consideration reasonable material and process variation, that is applied to long term resin data to provide a design safety margin 1.4.7 service life period of time in years in which the tank remains in use as specified by the manufacturer 1.4.8 service temperature <ambient temperature> average ambient temperature that the tank is exposed to within a calendar year, for tanks where the stored liquid is at ambient temperature <stored liquid> maximum temperature of the stored liquid, for tanks where the stored liquid is above ambient temperature Note 1 to entry: Published meteorological data is used for derivation of the service temperature for tanks where the stored liquid is at ambient temperature. The Bureau of Meteorology provides average annual ambient temperature isothermic information. 1.4.9 shall indicates that a statement is mandatory 1.4.10 should indicates a recommendation 1.4.11 structural design life period of time in years that forms the basis of the structural design 1.5  New designs and innovations This Standard does not prevent the use of alternative methods of design or construction using rotationally moulded components not specifically referred to, provided that the requirements of Sections 2, 3, 4 and 5 are met.
2.7  UV resistance
2.7.1  Application The requirements of this Section shall apply to base resins where base resins are UV stabilized. Where UV stabilizers are added at the final compounding stage, this Section shall apply to natural (unpigmented) powders. All UV testing shall be performed on natural (non-pigmented) base resin material to establish a minimum performance level for the material being tested. 2.7.2  Exposure to sunlight for non-buried and partially buried tanks When tested in accordance with ASTM D2565, the polymer compound for tanks, fusion-bonded fittings and welding rods shall contain UV stabilizers such that the natural (non-pigmented) compound will retain 50 % tensile elongation after 8 000 h of exposure in a Xenon‑Arc weatherometer. C2.7.2 It is the intention of Committee PL-046 to propose a future amendment to this Standard. The proposed amendment would replace the text in Clause 2.7.2 with the following: “When tested in accordance with ASTM D2565, the polymer compound for tanks, fusion-bonded fittings and welding rods shall contain UV stabilizers such that the natural (non-pigmented) compound will retain 50 % tensile elongation after 12 000 h of exposure in a Xenon-Arc weatherometer.”