摘要:
In a mold for casting a billet with a curved type continuous casting apparatus, D0 (m) is an inner diameter at a lower mold edge and R0 (m) is a curvature radius of an outer curvature side at the lower mold edge. When a rate of change Tp (%/m) in mold inner diameter per unit length along a casting direction is Tp=(1/D0)×(dD/dx)×100 (%/m), and when a rate of change Rp (%/m) in curvature radius of an outer curvature side per unit length along the casting direction is Rp=(1/R0)×(dR/dx)×100 (%/m), the rate of change Tp in mold inner diameter and the rate of change Rp in curvature radius satisfy a relationship expressed Rp=(Tp/2)×(D0/R0), where D is a mold inner diameter at a distance x away from an upper mold edge and R in Formula 2 is a curvature radius of the outer curvature side at the distance x.
摘要:
An arm material for an upper arm or a lower arm is provided which constitutes a double wishbone suspension or the like of an automobile and which has a flat, hollow, closed cross-sectional shape and enables further decreases in size, decreases in weight, and increases in strength.An arm material for an automobile suspension has a body made from a parts material made by metal. The parts material made by metal has a flat, hollow, closed cross-sectional shape having a pair of opposing long sides and is formed from a single member in its lengthwise direction. The body has at least a first bent portion which is bent in a plane roughly parallel to the pair of long sides.
摘要:
An elongation rolling control method is provided which can manufacture a hollow shell of high dimensional accuracy and can suppress rolling problems. It is an elongation rolling control method in which the groove bottom wall thickness of a hollow shell P in stand #1 having an ultrasonic wall thickness wall gauge 1 installed between it and stand #2 is measured, the outer diameter of a mandrel bar B is calculated based on the set value of the roll gap in stand #1 and the groove bottom wall thickness of the hollow shell P, the location in the lengthwise direction of the mandrel bar B for which the outer diameter was calculated is determined based on positional information on a bar retainer BR, the distribution in the lengthwise direction of the outer diameter of the mandrel bar is calculated by repeating the above steps, the location in the lengthwise direction of the mandrel bar which contacts the hollow shell in a subsequent stand is determined based on positional information on the bar retainer, and the roll gap in the subsequent stand is set based on the outer diameter of the determined location in the lengthwise direction of the mandrel bar.
摘要:
A steel pipe with a wall thickness over 30 mm is subjected to heat treatment of quenching and tempering using a temperature range of at least not less than 750° C. during the heating stage, makes it possible to obtain a heavy-wall seamless steel pipe having excellent toughness by resulting grain refinement. Quenching is by performing water cooling after heating the steel pipe to a temperature in the range of not less than 900° C. to not more than 1000° C. by using, as a heating means, induction heating at a frequency of not more than 200 Hz. Tempering is performed at a temperature in the range of not less than 500° C. to not more than 750° C. Preferably, after the heating by induction heating, a soaking treatment is performed in the temperature range of not less than 900° C. to not more than 1000° C. for 10 minutes or less followed by water cooling.
摘要:
A cooling apparatus of a steel sheet, which is excellent in discharging water without hindering the movement of a steel sheet, is disposed on a lower process side of a final stand in a row of hot finish rolling mills. The apparatus includes a plurality of cooling nozzles arranged to cool a steel sheet transported on transporting rolls, wherein the cooling nozzles are arranged on upper and lower surface sides of an area in which the steel sheet passes. A lower surface guide is arranged on the lower surface side with the lower surface guide comprising inlet holes through which cooling water sprayed from the cooling nozzles on the lower surface side passes and outlet holes through which the cooling water passes, dropping downwardly to be discharged. The inlet holes and the outlet holes are arranged alternately in a moving direction of the steel sheet.
摘要:
The method for manufacturing a martensitic stainless pipe includes heating the steel pipe until the external surface temperature thereof reaches a predetermined temperature not lower than A3 transformation point+20° C. and not higher than 980° C. The heated steel pipe is first water cooled until the external surface temperature thereof reaches a predetermined temperature not lower than 350° C. The water cooled steel pipe is air cooled until the external surface temperature thereof reaches a predetermined temperature not higher than 250° C. The air cooled steel pipe is either water or air cooled until the external surface temperature thereof reaches normal temperature. The cooling rate of the steel pipe in the first cooling step is determined according to the wall thickness of the steel pipe so that the amount of heat recuperation for the external surface temperature of the steel pipe in the second cooling step is not higher than 50° C.
摘要:
A rotary eddy current flaw detection probe device has a plurality of Θ-shaped eddy current flaw detection probes attached in a rotating disc for detecting flaws in all directions regardless of the flaw direction. Four Θ-shaped eddy current testing probes P11 to P22 are arranged around the rotation center Ds1 of a rotating disc 111, and are embedded in the disc 111. The coil planes of detector coils Ds11 to Ds22 of the testing probes P11 to P22 are parallel with each other, and are perpendicular to the rotation plane of the rotating disc 111. The coil planes of the detector coils incline at an angle θ relative to a line Y passing through the centers Ps11 and Ps12 of the probes P11 and P12. The detector coils Dc11 and Dc12 are cumulatively connected to each other, and the detector coils Dc21 and Dc22 are differentially connected to each other.
摘要:
A welding material, to be used for welding a base metal made of an austenitic alloy comprising C≦2.0%, Si≦4.0%, Mn: 0.01 to 3.0%, P: more than 0.03% to not more 0.3%, S≦0.03%, Cr: 12 to 35%, Ni: 6 to 80%, sol. Al: 0.001 to 1% and N≦0.3%, with the balance being Fe and impurities to a base metal made of another austenitic alloy, which comprises C: more than 0.3% to 3.0%, Si≦4.0%, Mn≦3.0%, P≦0.03%, S≦0.03%, Cr: more than 22% to 55%, Ni: more than 30% to not more than 70%, sol. Al: 0.001 to 1% and N≦0.3%, with the balance being Fe and impurities can suppress the weld solidification cracking which occurs in an austenitic alloy having a high P content and showing fully austenitic solidification. Therefore, the said welding material can be widely used in such fields where a welding fabrication is required. The said welding material may contain a specific amount or amounts of one or more elements selected from Cu, Mo, W, V, Nb, Ti, Ta, Zr, Hf, Co, B, Ca, Mg and REM.
摘要:
A martensitic stainless steel comprising C: 0.01-0.10%, Si: 0.05-1.0%, Mn: 0.05-1.5%, P: not more than 0.03%, S: not more than 0.01%, Cr: 9-15%, Ni: 0.1-4.5%, Al: not more than 0.05% and N: not more than 0.1% in mass %, and further comprising at least one of Cu: 0.05-5% and Mo: 0.05-5%, the residual being Fe and impurities, is provided, wherein the contents of Cu and Mo satisfy the following formula (a) or (b), 0.2%≦Mo+Cu/4≦5% (a) 0.55%≦Mo+Cu/4≦5% (b) and wherein the hardness is 30-45 in HRC and the carbide amount in grain boundaries of the prior austenite is not more than 0.5 volume %. The marensitic stainless steel has excellent properties regarding the sulfide stress cracking resistance, the resistance to corrosive wear and the localized corrosion.
摘要翻译:一种马氏体不锈钢,其包含C:0.01〜0.10%,Si:0.05〜1.0%,Mn:0.05〜1.5%,P:0.03%以下,S:0.01%以下,Cr:9〜15%,Ni :0.1-4.5%,Al:0.05%以下,N:0.1质量%以下,进一步含有Cu:0.05〜5%和Mo:0.05〜5%中的至少一种,残留物为Fe 提供Cu和Mo的含量满足下式(a)或(b):0.2%< NlE; Mo + Cu / 4≦̸ 5%(a)0.55%≦̸ Mo + Cu / 4& 5%(b),硬度在HRC中为30-45,前奥氏体的晶界中的碳化物量不大于0.5体积%。 锰矿不锈钢具有耐硫化物应力开裂性,耐腐蚀性和局部腐蚀性等优异性能。
摘要:
An ultrasonic testing apparatus for a pipe end portion, which enables accurate ultrasonic testing, comprises an ultrasonic probe disposed under the pipe end portion. The probe 1 transmits ultrasonic waves to the pipe end portion and receives the ultrasonic waves therefrom. A probe holder houses the probe which is disposed under the pipe end portion to face the pipe end portion and follows the pipe rotation. The probe holder comprises a coupling medium reserver part that surrounds a space between the probe and the pipe end portion to contain a coupling medium therein and comprises a coupling medium reserver part body into which the coupling medium is supplied. An annular bellows part, which communicates with the reserver part body, can expand and contract vertically and an annular spacer, which is attached to the upper side of the bellows part and an upper surface thereof has a flat horizontal surface.