1. Gas storage well is also called as the pressure vessel, so the special casing for the gas storage well shall be seamless steel pipe; |
| 2. Gas storage well works continuously under the variable pressure load, so antifatigue indicator shall be designed for the special casing: ≥25000 times. |
| 3. To ensure the anti-fatigue indicators of the casing, reduce the frangibility of materials, improve the toughness of materials and retard the occurrence of fatigue crack of special casing, therefore, requirements have been raised on the shock work indicators and yield strength ratio indicators of the casing, with the yield strength ratio for the materials designed as ≤0.90; |
| 4. Intensity index design for the special casing of gas storage well take into full account the requirements on thecasing joint intensity by the gas storage well depth (generally ≤500 m). The casing is designed as 80 steel grade and the yield strength of casing shall comply with δg≥80KSI; |
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5. For the special casing for the gas storage well, there shall be indicators for the resistance against the tensile stress (for oil well casing, the compressive stress on the casing in the circumferential direction by the strata) on the well wall in the circumferential direction by the high-pressure gas in the well, with the designed internal pressure resistance indicator bigger than 40Mpa. |
Main parameters of the gas storage well
Well tube diameter: ⊙177.8～⊙244.5（mm）（TP80QJ, special casing for gas storage well）
Nominal capacity: 1～10（m2）
Well depth:100～500（m）
Nominal working pressure: 25（MPa）
Storage media: Natural gas and other non-corrosive gas in conformity with GB 18047. |
