| 摘要 |
A pipe joint is described for driving pipes laid underground by the driving technique and having an inner pipe made of cast iron to which the force of pressure is applied during driving, wherein each driving pipe is constructed from the inner cast iron pipe formed without a socket and a coaxially disposed outer casing having a greater diameter than the cast iron pipe and forming a lost casing for an intermediate layer of cement mortar-like material between the inner and outer pipes. The pipe joint has at least one seal ring positioned on an end portion of the inner cast iron pipe protruding beyond the intermediate layer within a recess defined by a protruding end portion of the other driving pipe, the seal ring being overlapped by the protruding end portion of the other driving pipe.
|
