Waterworks Technology Development Organization Co., Ltd.

Akihito Totsugi

Kikuo Saito

Hideki Yoneyama

Atsushi Sakai

Yasushi Shimonaka

To enable efficient and easy attachment of a shutoff operation cover at a proper attaching position relative to two joining flange portions and also to restrict deformation in a leading end portion of a gate plate valve. A shutoff operation cover B is attached to two pipe portionsjointed and fastened together with a fastener. The shutoff operation cover B is capable of surrounding outer peripheries of the two joining flange portionsA,A under a sealed condition, and there is provided a gate plate valvein the form of a thin plate, the valve being insertable and withdrawable for shutting off conduits of the two pipe portions. As the gate plate valveis inserted to a conduit shutting position through a gap S formed between the two joining flange portionsA,A in association with a loosening operation of the fastener, the conduit is shut off between the two joining flange portionsA,A. When the shutoff operation cover B is attached to the two pipe portions, a leading endof the gate plate valvelocated at a conduit opening position is advanced into an annular gapformed on the outer peripheral sides of opposing faces of the two joining flange portionsA,A.

Method of shutting off conduit and pipe conduit shutoff apparatus

A spacer-less type pipe joint comprises a press ring which has a protruding portion at its outer periphery and is fitted to an outer periphery of one end side of jointed pipe, a joint main body which has a protruding portion opposing the protruding portion of the press ring at a side opposing the press ring and a receiving opening portion which is extended toward the press ring at the inner peripheral side of the protruding portion of the joint main body and which is fitted to the outer periphery of the jointed pipe with a peripheral clearance being formed there between, a securing tool which can move the press ring in a direction of the joint main body, and a packing ring which is provided between the joint main body and the jointed pipe and fitted into the receiving opening portion by its elastic deformation due to direct press of the press ring moved by operation of the securing tool.

Spacer-less type pipe joint and packing ring used for the same

A flexible pipe joint apparatus for use in a fluid (e.g., water) transport pipe system for maximally absorbing an external force such as a compression or tensile force applied to a pipe of the fluid transport system due to an earthquake, differential settlement, thermal expansion or contraction of the pipe per se, thus preventing resultant damage at a weak portion of the pipe. The apparatus includes a receiving tubular member and an inserting tubular member insertable into and connectable with the receiving tubular member along a tube axial direction. A stopper portion is formed in an outer peripheral face of the inserting tubular member, the stopper portion projecting radially outward from the outer peripheral face. A retaining portion is formed in an inner peripheral face of the receiving tubular member, the retaining portion coming into contact with the stopper portion of the inserting tubular member so as to prevent slidable displacement between the two tubular members at least on a withdrawal side in a predetermined relative slidable range of the tubular members. The stopper portion includes a plurality of projections formed at a plurality of positions along a periphery of the inserting tubular member. The retaining portion of the receiving tubular member includes a plurality of detaching recesses, each said recess allowing passage of each of the projections axially relative to the detaching recess only when the receiving tubular member and the inserting tubular member are located in a predetermined phase relationship with each other.

Flexible fluid-transport pipe joint apparatus

A pipe connecting apparatus for connecting a first pipe with a second pipe inserted into the first pipe member is disclosed. The apparatus includes an elastic seal to be disposed within a gap formed between an inner peripheral face of the first pipe and an outer peripheral face of the second pipe, the elastic seal being compressed in an axial direction along the axis of the first pipe for sealing the gap, a press ring fitted on the second pipe, the press ring being movable on the outer peripheral face of the second pipe in the axial direction, and a retainer member fitted on the second pipe, the retainer member having a locked condition in which the retainer member is pressed against the second pipe and a released condition in which the retainer member is radially expanded to be released from the locked condition, the retainer member being switched over from the released condition to the locked condition in association with a movement thereof relative to the press ring. A sequentially operative mechanism is operative to press the elastic seal alone in the axial direction while the retainer member is at the released condition in a first state where the compressive force is low, the sequentially operative mechanism being operative to allow the retainer member to be switched over to the locked condition in a second state where the compressive force is high.

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Sanda, Japan

Akihito Totsugi