Nippon Steel Corporation

Nippon Steel Sumitomo Metal Corporation

Sankosha Corporation

Hidetoshi Ito

Hiroshi Yamashita

Kazutoshi Ichikawa

Noriaki Onodera

Junpei Miyata

Provided is a steel H-shape for low temperature service including a predetermined chemical composition. A CEV obtained by CEV=C+Mn/6+(Cr+Mo+V)/5+(Ni+Cu)/15 is 0.40 or less. A sum of an area ratio of one or both of ferrite and bainite at a 1/4 position from an outer side across a thickness of a flange and a 1/6 position from an outer side across a flange width is 90% or more, and an area ratio of a hard phase is 10% or less. An effective grain size is 20.0 &#x3bc;m or less, and a grain size of the hard phase is 10.0 &#x3bc;m or less. 30 pieces/mmor more Ti oxides having an equivalent circle diameter ranging from 0.01 to 3.0 &#x3bc;m are included. The thickness of the flange ranges from 12 to 50 mm.

Steel H-shape for low temperature service and manufacturing method therefor

In a steel sheet pile according to the present invention, a carbon equivalent CEis 0.260 to 0.500, a structure includes a ferrite, a pearlite, a Widmanst&#xe4;tten ferrite, and a precipitate, the precipitate is one or both of Nb carbonitride and V carbonitride, a total number density of the precipitate is 0.10 to 0.30 pieces/&#x3bc;m, a total area ratio of the ferrite and the pearlite is 70% or more, an area ratio of the Widmanst&#xe4;tten ferrite is 1% or more, an average grain size of the ferrite and the pearlite is 10 to 80 &#x3bc;m, and a yield strength is 460 MPa or more.

Steel sheet pile and method for manufacturing the same

An isolatoris formed with an isolation transformerthat blocks an abnormal voltage entering from a communication lineand protects a protection target device. A pulse transformerin the deviceincludes a primary windingconnected to a secondary windingof the transformerand a secondary windingconnected to an inner circuit. A medium tap of the primary windingis grounded through an inner capacitance Ci of the device. A parasitic capacitance Cs between the primary windingand the secondary windingof the transformerand the inner capacitance Ci are connected in series, an abnormal voltage is divided by the capacitance Cs and the capacitance Ci, and a capacitance value of the capacitance Cs is set such that the divided voltage of the capacitance Ci is equal to or below a predetermined value.

Growing community of inventors

Tokyo, Japan

Hidetoshi Ito