PURPOSE:To produce an extra-thick tempered high tension steel plate having excellent low-temp. toughness by subjecting a steel plate of a specific thickness consisting of a specific compsn. successively to heating, air cooling, force cooling, and tempering under specific conditions. CONSTITUTION:The steel plate of 75-200mm thickness which contains, by weight %, 0.03-0.20% C, 0.05-0.50% Si, 3.0% Mn, =2 kinds of 0.01-1.50% Cu, 0.01-1.50% Cr, and 0.01-1.50% Mo, and consists of the balance iron and inevitable impurities and has 26-42 parameter (x) expressed by the formula is prepd. This steel plate is then heated to a 900-1,050 deg.C range and is air-cooled down to 800-850 deg.C, following which the steel plate is forcibly cooled down to =1 deg.C/sec cooling rate and is then tempered at the Ac1 transformation point or below. The extra-thick tempered high tension steel plate having the excellent low-temp. toughness and about >=80kgf/mm tensile strength is obtd.

Production of extra-thick tempered high tension steel plate having excellent low-temperature toughness

PURPOSE:To provide a structural steel for low temp. use applicable to a thick structural material. CONSTITUTION:The steel has a composition consisting of, by weight, 0.03-0.12% C, 0.5-1.2% Mn, 2-3.5% Ni, <=2% Cr, 0.3-O.6% Mo, 0.01-0.06% Al, further 0.01-0.O5% V and/or 0.01-0.05% Nb, and the balance Fe with inevitable impurities. Moreover, it is desirable to regulate the allowable contents of Si, S, and O among the inevitable impurities to <=0.1%, <=0.003%, and <=0.003%, respectively. By this method, the structural steal for low temp. use, having high strength and combining superior toughness at low temp., fatigue characteristics, and weldability, can be obtained. This steel also is applicable to a thick structural material.

Structure steel for low temperature use

The invention provides a high-wearability roller flat head. The high-wearability roller flat head comprises a flat head body and a wear-resisting plate, a groove is formed in a flat head plane of the flat head body, the wear-resisting plate is matched with the groove in shape and size and is inlaid into the groove, the upper surface of the wear-resisting plate is flush with the surface of the flat head plane, and the wear-resisting plate is fixedly connected with the flat head body. The high-wearability roller flat head has the advantages of being simple in structure, low in manufacturing cost, convenient to use, suitable for industrial production and the like.

High-wearability roller flat head

PURPOSE:To eliminate the deterioration in the processing capability of a time division exchange by rewriting a program via a highway of a time division switch CONSTITUTION:When a terminal equipment T sends a rewrite request, the request is sent from a control means 1 of a line interface device (IE2) 30 connecting to a terminal equipment to a CPU 12 of a time division exchange, the CPU 12 sends it from a line interface device (IE1) 30 to be rewritten side and the control means 1 connects a time division multiple line 6 via a switch 9 On the other hand, the CPU 12 connects both the line interface devices IE1, IE2 via a time division switch TSW The control means 1 at the rewritten side receives rewrite information through a time division multiplex line 6 and the content of a 1st storage means 2 is rewritten by a program of a 2nd storage means 4 Thus, a program of an optional line interface device is rewritten through the time division switch from the terminal equipment

Program rewrite system

The invention relates to a groove modifying method for reducing roller consumption. The method is characterized by comprising a first step of spraying a coloring penetrant on the roller groove which is off line after used once or twice, and fully permeating after 15-30min; and a second step of processing the groove with the coloring penetrant into a roller groove hole type in last few sorties, and guaranteeing that the processed position is not provided with the coloring penetrant. The groove modifying method has the advantages of increasing roller using times, improving roller utilization rate, lowering roller consumption, reducing production cost and improving roller processing efficiency.

Groove modifying method for reducing roller consumption

PURPOSE:To provide superior toughness at low temp to a cast steel having a specified composition contg Mn, Nb, B, N, Al and/or Ti, S and Ca and/or REM by hardening or normalizing the cast steel and tempering it CONSTITUTION:A cast steel having a composition consisting of, by weight, 002-018% C, 0001% in total of one or more kinds of rare earth metals such as La and Ce, 001-012% Al and/or 001-006% Ti and the balance Fe with inevitable impurities is cast The cast steel is heated to 900-1,050 degC, cooled once, hardened or normalized at 1,000-1,100 degC and tempered

Manufacture of cast steel having superior toughness at low temperature

PROBLEM TO BE SOLVED: To obtain a roll having wear resistance and resistant to large rolling load by using a roll-core material on which grooved parts in the circumferential direction in positions where the arrangement of caliber is planned and carving calibers in the circumferential direction on the outer-layer metal after depositing the outer-layer metal on the surface of the roll-core material. SOLUTION: After heating the outer layer of the roll-core material 5 by a high frequency, the molten metal for outter-layer metal of high-speed steel containing W which is separately melted is poured into a molding flask provided on the circumference of the roll-core material and the outer-layer metal is deposited on the roll-core material 5. After that, the caliber roll is manufactured by carving the calibers in the parts equivalent to the groove parts by cutting by machining and making the thickness in the flat parts of barrel except the calibers uniform. In this way, even when the depth (t) of the caliber is greater than the deposite thickness T of the outer-layer metal, the bottom of the caliber 3 does not reach the roll-core material 5 and the whole surface of the calibers 3 of the roll is covered with the outer-layer metal excellent in wear resistance and surface roughening resistance.

Manufacture of composite roll

PURPOSE:To obtain a vibration-absorbing base having a great vibration- regulating property and having a high durability by a method in which a nonmetal or vibration absorber having a great specific damping function is buried in recessions formed in a cast iron or steel piece and covered with an other cast iron or steel piece. CONSTITUTION:One or many recessions 2 are formed in a cast iron or steel piece 1 and paced with a nonmetal substance 3 or/and a vibration absorber 4 having a great specific damping function. The cast iron or steel piece 1 is covered with an other cast iron or steel piece 5 to prevent the leak of the substance buried to the outside. The vibration-absorbing base suitable for even environments where oil and fine powdery dust are present, such as the base of machine, can thus be obtained.

Manufacture of vibration-absorbing base

PURPOSE:To provide superior weldability and resistance to environmental corrosion, by properly blending, further, either or both of Ca and REM with a steel which is low-C and low-S and in which Cr, Ni, Mo, Si, Mn, N, and Al are properly blended and by subjecting the above steel to casting and then to heat treatment under specific conditions. CONSTITUTION:The steel has a composition consisting of, by weight, 0.002% Ca and >0.001%, in total, of REM such as La, Ce, etc., and the balance Fe with inevitable impurities and further satisfying Ni+30C+0.5Mn=5.5-9 and Cr=Mo+1.5Si=24-30. A steel material cast from this steel is heated to 1,000-1,100 deg.C and then cooled through the range of 900-500 deg.C at an average cooling rate of >=10 deg.C/min.

Moriyama Yasushi

Papers

Manufacture of cast steel having superior toughness at low temperature

Manufacture of composite roll

Manufacture of vibration-absorbing base

Manufacture of cast steel product excellent in weldability and resistance to environmental corrosion