Kubota Corporation

Kohei Ikeda

Shozo Kishi

Takaaki Kagawa

Takashi Yokomizo

Yoshinori Itani

Yuito Komaru

Shogo Kaneko

Masataka Shimomura

Daichi Higasa

Keita Oda

Ryunosuke Tanaka

Kazuya Ito

Kazuma Harada

A watertightness testing device () for performing a watertightness test of a joined section between joined pipes (and), the watertightness testing device () including a testing device body () and a moving operation rod () for moving the testing device body () in the pipes in a pipe axial direction (B) from outside an end section of the pipes, wherein the moving operation rod () is provided in the testing device body () and extends along the pipe axial direction (B), main supporting members (and) for supporting the moving operation rod () are provided on the moving operation rod () outside the pipe (), and the main supporting members (and) have a rotatable main rolling member () in a lower end section, the main supporting members (and) are switchable between a supporting posture (K) in which the main supporting members (and) support the moving operation rod () outside of the pipes and a folded posture in which the main supporting members (and) are folded inside the pipes, and the main supporting members (and) are urged from the folded posture toward the supporting posture (K).

Watertightness testing device and watertightness testing method

A watertightness testing method for testing watertightness of a joined section () where one end section of a second pipe () is joined to a first pipe (), the watertightness testing method including: inserting a testing device body () into the first pipe (); attaching an assembling device () to another end section of the second pipe (); attaching a pulling device () to the assembling device () and connecting the pulling device () to a strap-shaped member () having been wound in advance around an outer circumference of the first pipe (); operating the pulling device () and pulling the strap-shaped member () in a separating direction of the second pipe () to have a reaction force generated in the second pipe () cause the second pipe () to be pulled in a joining direction (G), the one end section of the second pipe () to be inserted into the first pipe (), and the second pipe () to be joined to the first pipe (); and operating a moving operation rod () provided in the testing device body () from outside of the other end section of the second pipe () in a state where the second pipe () is being pulled in the joining direction (G) to move the testing device body () to the joined section ().

Watertightness testing method and assembling device

A pipe joint in which a seal body and a spacer are mounted from the insides of pipes, wherein: a spigot of one pipe is inserted into a socket of the other pipe; and an annular accommodation space is formed between the inner circumference of the socket and the outer circumference of the spigot. Inside the accommodation space are accommodated: a seal body for sealing the gap between the socket and the spigot; a push ring that presses the seal body to keep the seal body in a compressed state; and a spacer that maintains the interval between the push ring and the deep end of the socket in the pipe axial direction.

Pipe joint, push ring for pipe joint, method for joining pipes

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.

Pipe joint

Growing community of inventors

Hyogo, Japan

Kohei Ikeda