Abstract: A buried piping replacement period prediction apparatus includes a buried piping attribute data acquisition unit and an exceedance-probability-of-corrosion-depth prediction unit. The buried piping attribute data acquisition unit acquires attribute data of buried piping. The attribute data of the buried piping includes a first environmental factor of the buried piping, a first burial period of time of the buried piping, and a nominal pipe wall thickness or an allowable corrosion depth of the buried piping. The exceedance-probability-of-corrosion-depth prediction unit calculates an exceedance probability of corrosion depth of the buried piping in a certain period from an exceedance-probability-of-corrosion-depth prediction model for the first environmental factor, the first burial period of time, and the nominal pipe wall thickness or the allowable corrosion depth.

Abstract: Disclosed is a pipe made of an iron-base material, having a corrosion prevention layer formed on the surface thereof. The corrosion prevention layer includes a Zn—Sn sprayed coating including Sn in a content of more than 1% by mass and less than 50% by mass and the balance composed of Zn. Alternatively, the corrosion prevention layer includes a Zn—Sn—Mg sprayed coating including Sn in a content of more than 1% by mass and less than 50% by mass, Mg in a content of more than 0.01% by mass and less than 5% by mass and the balance composed of Zn. Preferably, the sprayed coating of the corrosion prevention layer includes at least any one of Ti, Co, Ni and P, and the content of each of these elements is more than 0.001% by mass and less than 3% by mass.

Abstract: Disclosed is a pipe made of an iron-base material, having a corrosion prevention layer formed on the surface thereof. The corrosion prevention layer includes a Zn—Sn sprayed coating including Sn in a content of more than 1% by mass and less than 50% by mass and the balance composed of Zn. Alternatively, the corrosion prevention layer includes a Zn—Sn—Mg sprayed coating including Sn in a content of more than 1% by mass and less than 50% by mass, Mg in a content of more than 0.01% by mass and less than 5% by mass and the balance composed of Zn. Preferably, the sprayed coating of the corrosion prevention layer includes at least any one of Ti, Co, Ni and P, and the content of each of these elements is more than 0.001% by mass and less than 3% by mass.

Abstract: Disclosed is a pipe made of an iron-base material, having a corrosion prevention layer formed on the surface thereof. The corrosion prevention layer includes a Zn—Sn sprayed coating including Sn in a content of more than 1% by mass and less than 50% by mass and the balance composed of Zn. Alternatively, the corrosion prevention layer includes a Zn—Sn—Mg sprayed coating including Sn in a content of more than 1% by mass and less than 50% by mass, Mg in a content of more than 0.01% by mass and less than 5% by mass and the balance composed of Zn. Preferably, the sprayed coating of the corrosion prevention layer includes at least any one of Ti, Co, Ni and P, and the content of each of these elements is more than 0.001% by mass and less than 3% by mass.

Abstract: Disclosed is a pipe made of an iron-base material, having a corrosion prevention layer formed on the surface thereof. The corrosion prevention layer includes a Zn—Sn sprayed coating including Sn in a content of more than 1% by mass and less than 50% by mass and the balance composed of Zn. Alternatively, the corrosion prevention layer includes a Zn—Sn—Mg sprayed coating including Sn in a content of more than 1% by mass and less than 50% by mass, Mg in a content of more than 0.01% by mass and less than 5% by mass and the balance composed of Zn. Preferably, the sprayed coating of the corrosion prevention layer includes at least any one of Ti, Co, Ni and P, and the content of each of these elements is more than 0.001% by mass and less than 3% by mass.

Abstract: An annular sealing material seals a pipe joint between a socket and a spigot. The sealing material includes a bulb part which is composed of a first bulb, a second bulb located closer to the inner side of the socket than the first bulb, and a narrow part present between the first and second bulbs. The first bulb is pressed against the inner circumferential surface of the socket. The second bulb is pressed against the outer peripheral surface of the spigot. The second bulb is inclined towards the pipe center from the first bulb in a natural state before it is provided between the socket and the spigot. The inner diameter of the second bulb is smaller than the outer diameter of the spigot in the natural state. The second bulb is extensible in the pipe diameter direction due to elastic deformation of the narrow part.

Abstract: Disclosed is a pipe made of an iron-base material, having a corrosion prevention layer formed on the surface thereof. The corrosion prevention layer includes a Zn—Sn sprayed coating including Sn in a content of more than 1% by mass and less than 50% by mass and the balance composed of Zn. Alternatively, the corrosion prevention layer includes a Zn—Sn—Mg sprayed coating including Sn in a content of more than 1% by mass and less than 50% by mass, Mg in a content of more than 0.01% by mass and less than 5% by mass and the balance composed of Zn. Preferably, the sprayed coating of the corrosion prevention layer includes at least any one of Ti, Co, Ni and P, and the content of each of these elements is more than 0.001% by mass and less than 3% by mass.