The present invention relates to structural steel that can be desirably used in offshore structures and the like, more specifically, to a thin steel plate having excellent low-temperature toughness and CTOD properties, and to a method for manufacturing the same.

The present invention reveals an ultra-thin ultra-high strength steel wire, a wire rod for an ultra-thin ultra-high strength steel wire and its producing method. The chemical components of the wire rod comprise in percentage by mass: C 0.90˜0.96%, Si 0.12˜0.30%, Mn 0.30˜0.65%, Cr 0.10˜0.30%, Al≤0.004%, Ti≤0.001%, Cu≤0.01%, Ni≤0.01%, S≤0.01%, P≤0.01%, O≤0.0006%, N≤0.0006%, and the balance is Fe and unavoidable impurity elements. The wire rod for the ultra-thin ultra-high strength steel wire may be used as a base material for producing the ultra-thin ultra-high strength steel wire having a diameter in a range of 50˜60 μm and a tensile strength larger than or equal to 4500 MPa.

A continuous induction heat treating apparatus is provided including a conveyor path defining an axis for a workpiece to be conveyed through the apparatus. The apparatus includes an induction heating station positioned along the conveyor path and operable to induce heating in the workpiece as the workpiece is conveyed through the induction heating station. A quenching station is positioned in a downstream direction from the induction heating station. The quenching station is coupled to a water supply and includes a plurality of sprayers in fluid communication with the water supply and operable to spray water toward the axis for quenching the workpiece as the workpiece is conveyed through the quenching station. The apparatus further includes a quench adjustment mechanism including an actuator coupled to at least a first one of the plurality of sprayers for re-positioning a point of intersection defined between the first sprayer and the axis.

In one embodiment, a method for manufacturing a pipe bend is disclosed, comprising: heating, with an induction coil, a first annular band of a wall of a first end portion of a moving pipe; directing quenching fluid toward an outer and inner surface of the first annular band; heating a second annular band of a wall of a bend portion of the moving pipe; directing the quenching fluid toward an outer and inner surface of the second annular band; decreasing a speed of the pipe while moving the induction coil from stationary and maintaining a relative speed between the pipe and the induction coil substantially constant; heating a third annular band of a wall of a second end portion of the pipe while moving the induction coil; and directing the quenching fluid toward an outer surface and an inner surface of the third annular band while moving the induction coil.

An process for the on-line quenching of seamless steel tube using residual heat, a method for manufacturing a seamless steel tube, and a seamless steel tube. The process for the on-line quenching of a seamless steel tube comprises the following steps: when the temperature of a tube is higher than Ar3, evenly spraying water along a circumferential direction of the tube so as to continuously cool the tube to be not higher than T° C., the cooling rate being controlled to be E1° C./s to E2° C./s to obtain a microstructure with martensite as the main composition, wherein T=Ms−95° C., Ms represents the martensitic phase transition temperature, E1=20×(0.5−C)+15×(3.2−Mn)−8×Cr−28×Mo−4×Ni−2800×B, and E2=96×(0.45−C)+12×(4.6−Mn), and the C, Mn, Cr, Ni, B and Mo in the equations each represents the mass percentages of corresponding elements in the seamless steel tube.

Device for cooling flat rolled material with a liquid coolant has at least one cooling bar, which is arranged above the conveying path and to which the liquid coolant is fed. A plurality of outlet tubes have, in a flow direction of the liquid coolant, an initial portion, which proceeds from the inlet opening and extends upward, a middle portion, which adjoins the initial portion, and an end portion, which adjoins the middle portion and extends downward and to the output opening. The middle portion contains a vertex at which the coolant flowing through the outlet tube in question reaches a highest point. The outlet openings are located above the cooling bar. A height distance (h1) of the inlet opening from the vertex is at least twice as large, in particular at least three times as large, as a height distance (h2) of the outlet opening from the vertex.

A cooling device for a metal plate includes a plurality of first nozzles and a plurality of second nozzles disposed on both sides of the metal plate, respectively, in a thickness direction of the metal plate across a pass line of the metal plate. The plurality of first nozzles form a staggered array in which a pitch in a width direction of the metal plate is Xn, a pitch in a longitudinal direction of the metal plate is Yn, and an offset amount in the width direction of a pair of first nozzles disposed adjacent to each other in the longitudinal direction is ΔXn. The plurality of second nozzles form a staggered array in which a pitch in the width direction is Xn, a pitch in the longitudinal direction is Yn, and an offset amount in the width direction of a pair of second nozzles disposed adjacent to each other in the longitudinal direction is ΔXn. The staggered array of the first nozzles and the staggered array of the second nozzles are disposed offset from each other such that, a center of the second nozzle is at a position offset by a shift amount S from a center of the first nozzle in the width direction, and the center of the second nozzle is positioned in a region defined by an oval having a semi-axis of ΔXn/4 in the width direction and a semi-axis of Yn/3 in the longitudinal direction. The shift amount S is expressed by S=m×ΔXn/2, where m is an odd number such that S is closest to Xn/2.

Described herein is a method for quenching a hot metal part. The method may comprise selecting a first node located at about a slowest cooling point of the metal part and a second node located at about a fastest cooling portion of the metal part. The method may also comprise quenching the metal part to a finish temperature with the requirement that there is a temperature difference of between about 5° C. and about 30° C. during a quench cycle. The quench cycle may start from a first time when the second node is about 5° C. above a martensite start temperature of the specific metal or metal alloy of the metal part, and end at a second time when the first node is at a temperature which is about or below a martensite finish temperature of the specific metal or metal alloy.

An apparatus (100) for cooling long products is provided, the apparatus (100) having a coolant supply line (42) for supplying a coolant and a plurality of cooling devices (70), each connected to the coolant supply line (42) via an individually adjustable control valve (90), whose coolant delivery depends is each case on a degree of opening of the respective control valve (90), so that distribution of the coolant delivery along the travel direction can be flexibly adjusted by individually setting the degrees of opening of the control valves (90).

In an example implementation, a sintering system includes optical fiber installed into a sintering furnace. A support structure inside the furnace is to support a token green object in a predetermined position and to hold a distal end of the fiber adjacent to the predetermined position. A light source is operably engaged at a proximal end of the fiber to transmit light through the fiber into the furnace. A light detector is operably engaged at the proximal end of the fiber to receive reflected light through the fiber that scatters off a surface of the token green object.