Abstract: A railway track and derailment prevention device has main bodies installed on left and right sides of a bogie main body of a vehicle, and thick plates are vertically slidable in wide grooves provided in the main bodies. During a right turn of the vehicle, a centrifugal force causes a left flange to ride on a left rail, the left main body moves obliquely upward toward the rail, a front surface of the thick plate collides with a side surface of a rail head, an L-shaped hook of the thick plate collides with an eave of the rail head, and the main body further floats, thereby cutting a positioning pin between the main body and the thick plate. The main body is guided by the thick plate, sprung up almost vertically, and then, dropped, and the wheel is returned onto the rail, and the derailment is prevented.

Abstract: The present invention relates to blocking a flow of crude oil or natural gas from a steel pipe for extracting the oil or the like that has been installed in the sea when the steel pipe is broken. When a steel pipe 4 for petroleum well in the deep sea is broken, a carrying pipe 6 is inserted from a hole 5 that is a broken point in the steel pipe 4 to a predetermined depth and is fixed. The carrying pipe 6 is an elongated pipe made of nonmagnetic material such as synthetic resin. The carrying pipe 6 has a diameter that is approximately one-half the diameter of the steel pipe 4. A circular mesh plate 8 is hung at a tip portion of the carrying pipe 6.

Abstract: The present invention relates to blocking a flow of crude oil or natural gas from a steel pipe for extracting the oil or the like that has been installed in the sea when the steel pipe is broken. When damage occurs to a steel pipe 4 for petroleum or natural gas well that has been installed in the sea, in order to send magnetic particles 21 or the like into the seafloor through an carrying pipe 6 that has been installed and suspended inside the steel pipe 4, the outflow of petroleum or the like coming from a lower portion of the carrying pipe 6 is blocked by a gate valve 20 provided at a lower portion of a feeding equipment 12 for feeding magnetic particles or the like attached to an upper opening 7 of the carrying pipe 6.

Abstract: A method of producing plastic pipe having air channels axially extending through the wall thereof, with at least one of the respective ends of the air channels being closed by an annular slotted channel-closure filled with a caulking material in its annular slot. The channel-closure is force-fitted on the pipe end, so that the caulking material is pressed into the air channels.

Abstract: For the purpose of making a joint socket comprising at least two portions, namely a portion for receiving a plastic pipe end and another portion into which a rubber ring is fitted, a device for heating and softening a plastic pipe end and enlarging the radius of the softened pipe end to twice its size which includes, an inwardly slanted portion between a first outwardly slanted portion and a second outwardly slanted portion whose radius becomes smaller as it comes nearer to the front end thereof. As the result, the frictional resistance between an improved core and the radius enlarged softened pipe is reduced to a value which enables the device to be operated such that wall-thickened sockets can be made without loss of wall thickness subsequent to the radius enlarging process.

Abstract: For the purpose of making a joint socket comprising at least two portions, namely a portion for receiving a plastic pipe end and another portion into which a rubber ring is fitted, a method of heating and softening a plastic pipe end and enlarging the radius of the softened pipe end to twice its size which includes, an inwardly slanted portion between a first outwardly slanted portion and a second outwardly slanted portion whose radius becomes smaller as it comes nearer to the front end thereof. As the result, the frictional resistance between an improved core and the radius enlarged softened pipe is reduced to a value which enables the method to be carried out such that wall-thickened sockets can be made without loss of wall thickness subsequent to the radius enlarging process.

Abstract: A pipe joint in which an inner pipe is telescoped in an outer pipe includes a first and second expanded portion on the outer pipe. A packing member is disposed in the annular space between the second expanded portion and the inner pipe and a ring element is disposed in aligned annular grooves in the inner circumferential wall of the second expanded portion and the packing member. The ring element has a radial thickness equal to approximately one-half the difference between the inner diameters of the first and second expanded portions and serves to divide the packing member into two rim parts such that the latter are acted upon independently as the inner pipe is telescopically inserted into the outer pipe with the ring element preventing the rim parts from being axially displaced as the inner pipe is telescopically inserted in the outer pipe.