| 摘要 |
Gas pipe extenders to compensate for movements in ground-laid gas supply pipes caused by mining operations have been found to leak owing to their construction or have been inadequately extendible or capable of insufficient lateral movement. Greater axial extendibility and lateral movement are obtained with the aid of a metal bellows (1) and a corrosion-protection jacket (2) wound from strips and penetrating into the corrugation interstices (3) of the metal bellows. For use in supply pipes likely to be shifted by building operations and especially mining or earth tremors. |
