Division 3.6 Burst pressure ratios
The minimum burst pressure ratios, i.e. the minimum actual burst pressure of the container divided by its nominal working pressure, shall not be less than the values given in Table IV.3.6.
Table IV.3.6.
Minimum Burst Pressure Ratios
| Explanatory note: | |||||
For container designs using hybrid reinforcement, i.e. two or more different structural fibre types, consideration shall be given to the load share between the different fibres based on the different elastic moduli of the fibres. The calculated stress ratios for each individual structural fibre type shall conform to the specified values. Verification of the stress ratios may also be performed using strain gauges. The minimum burst pressure ratio shall be chosen such that the calculated stress in the structural fibres at the minimum burst pressure ratio times nominal working pressure divided by the calculated stress in the structural fibre at nominal working pressure meets the stress ratio requirements for the fibres used. | |||||
| Container type | |||||
|---|---|---|---|---|---|
| Construction | Type 1 | Type 2 | Type 3 | Type 4 | |
| All metal | 2,25 | ||||
| Over-wrap | Glass | 2,4 | 3,4 | 3,5 | |
| Aramid | 2,25 | 2,9 | 3,0 | ||
| Carbon | 2,25 | 2,25 | 2,25 | ||
| Hybrid | f1 | ||||
Annotations
Footnotes
- f1
For container designs using hybrid reinforcement, i.e. two or more different structural fibre types, consideration shall be given to the load share between the different fibres based on the different elastic moduli of the fibres. The calculated stress ratios for each individual structural fibre type shall conform to the specified values. Verification of the stress ratios may also be performed using strain gauges. The minimum burst pressure ratio shall be chosen such that the calculated stress in the structural fibres at the minimum burst pressure ratio times nominal working pressure divided by the calculated stress in the structural fibre at nominal working pressure meets the stress ratio requirements for the fibres used.