Document ID: chunk:federal_register_of_legislation:F2023L01530:body:0:p28
Version: federal_register_of_legislation:F2023L01530
Segment Type: other
Provision Reference: 
Character Range: 80071–82805

flaw generation: Two longitudinal saw cuts are made on the bottom outer surface of the unpressurized horizontal storage container along the cylindrical zone close to but not in the shoulder area. The first cut is at least 1.25 mm deep and 25 mm long toward the valve end of the container. The second cut is at least 0.75 mm deep and 200 mm long toward the end of the container opposite the valve;
              (b) Pendulum impacts: The upper section of the horizontal storage container is divided into five distinct (not overlapping) areas 100 mm in diameter each (see Figure 2). After 12 hours preconditioning at
               -40 °C in an environmental chamber, the centre of each of the five areas sustains the impact of a pendulum having a pyramid with equilateral faces and square base, the summit and edges being rounded to a radius of 3 mm. The centre of impact of the pendulum coincides with the centre of gravity of the pyramid. The energy of the pendulum at the moment of impact with each of the five marked areas on the container is 30 J. The container is secured in place during pendulum impacts and not under pressure.

         Figure 2
         Side view of container

         3.4. Chemical exposure and ambient-temperature pressure cycling test
         Each of the 5 areas of the unpressurized container preconditioned by pendulum impact (Annex 3, paragraph 3.3.) is exposed to one of five solutions:
              (a) 19 per cent (by volume) sulphuric acid in water (battery acid);
              (b) 25 per cent (by weight) sodium hydroxide in water;
              (c) 5 per cent (by volume) methanol in gasoline (fluids in fuelling stations);
              (d) 28 per cent (by weight) ammonium nitrate in water (urea solution); and
              (e) 50 per cent (by volume) methyl alcohol in water (windshield washer fluid).
         The test container is oriented with the fluid exposure areas on top. A pad of glass wool approximately 0.5 mm thick and 100 mm in diameter is placed on each of the five preconditioned areas. A sufficient amount of the test fluid is applied to the glass wool sufficient to ensure that the pad is wetted across its surface and through its thickness for the duration of the test.
         The exposure of the container with the glass wool is maintained for 48 hours with the container held at 125 per cent NWP (+2/-0 MPa) (applied hydraulically) and 20 (±5) °C before the container is subjected to further testing.
         Pressure cycling is performed to the specified target pressures according to paragraph 2.2. of this Annex at 20 (±5) °C for the specified numbers of cycles. The glass wool pads are removed and the container surface is rinsed with water the final 10 cycles