Provided is a steel plate for line pipes which exhibits excellent strength and ductility. Also provided is a process for the production of the steel plate. The steel plate is characterized by: having a steel composition which contains, by mass, 0.04 to 0.15% of C, 0.05 to 0.60% of Si, 0.80 to 1.80% of Mn, at most 0.020% of P, at most 0.010% of S, 0.01 to 0.08% of Nb, and 0.003 to 0.08% of Al with the balance being iron and unavoidable impurities, and which has a Ceq value of 0.48 or lower as defined by formula (1); having a mixed structure which is composed either of ferrite and pearlite or of ferrite and bainite-containing pearlite and which has a ferrite fraction of 60 to 95%; and exhibiting a yield strength of 450MPa or higher and a hydrogen content of 0.1ppm or lower. Ceq = C + Mn/6 + (Cu + Ni)/15 + (Cr + Mo + Nb + V + Ti)/5 + 5B ∙∙∙ (1)

Steel plate for line pipes with excellent strength and ductility and process for production of same

An article of manufacture is provided comprising a heat treated high strength low-alloy steel tubular product of the L-80 and N-80 type suitable for use as an oil well tubular member. The composition consists essentially of about 0.1 to 0.4% C, about 0.075 to 0.4% Mo, about 0.002 to 0.03% N, about 0.75 to 1.5% Mn, about 0.1 to 0.4% Si, and the balance essentially iron, the carbon and molybdenum contents being controlled and correlated such that for a carbon content ranging from about 0.1 to 0.25%, the molybdenum content ranges from about 0.075 to 0.25%; and for a carbon content ranging from about 0.25 to 0.4%, the molybdenum content ranges from about 0.2 to 0.4%.

Tubular high strength low alloy steel for oil and gas wells

PURPOSE:To provide good focusing performance of a color picture tube, by improving accuracy of the loading position of the limiting aperture unit in the focus electrode, and by solving the problem of the drop in the focusing voltage caused by the increase in the leakage current of the focus electrode due to the trimmed electron beam. CONSTITUTION:The limiting aperture unit 2 loaded within the focus electrode 4 through a ceramic support 1 is disposed so that each aperture is in alignment with the axis of each of the electron beams arranged in an in-line configuration. The ceramic support 1 is provided with the stepped holes 1a, 1b disposed in accordance with the interval between the electron beams, wherein the height h of the support and the depth l of the hole 1a may be adapted so that a suitable portion of the electron beam is trimmed by the limiting aperture 2 in accordance with the divergence angle of the electron beam. The limiting aperture unit 2 is automatically loaded in place with good accuracy within the focus electrode 4 since the unit is controlled by the preset dimensional accuracy provided in the ceramic support 1. Incidentally, in order to fix the ceramic support 1 within the focus electrode 4, a stopper 3 may be inserted therein and (the stopper 3 may be) welded to the focus electrode 4.

Color picture tube

Steel material having good resistance to hydrogenninduceddcracking

PURPOSE: A drug composition having improved water solubility of a water- insoluble or sightly water-soluble pharmacologically active substance, by incorporating the pharmacologically active substance with a glucosylated branched cyclodextrin. CONSTITUTION: (A) A water-insoluble or slightly water-soluble pharmacologically active substance such as steroid hormone agent, cardiac, neutral nervous system depressant, antibiotic or fat-soluble vitamin, etc., is incorporated with (B) a glucosylated branched cyclodextrin preferably a compound wherein 1W3 glucoses are bonded by α,1→6 bond to α-, β- or γ-cyclodextrin through oxygen atom of the cyclodextrin. The component B is premixed with 0.3W2.0pts.wt. water, blended with inclusion mol equivalent (usually equimolar) of the component A for 0.5 W several hours while stirring and powdered by a usually applicable drying method to give the aimed drug composition (inclusion compound). COPYRIGHT: (C)1988,JPO&Japio

Glucosylated branched cyclodextrin-containing composition

PURPOSE:To manufacture high tensile steel excellent in strength, toughness and weldability by rapid cooling low-carbon steel billets of a very few S content, after heating at a low temperature and rolling under a special condition. CONSTITUTION:Steel billets containing 0.005-0.08% C, =60% at >=850 deg.C and again rolled in the two phase region of (ferrite + austenite) of 20-70% ferrite volumetric rate at a reduction rate of 10- 60%. After being rolled, the billets are rapidly cooled at a quick cooling rate of more than 10 deg.C/sec to >=600 deg.C temperature in order to manufacture high tensile steel excellent in weldability.

Manufacture of high tensile steel

PURPOSE:To obtain the line pipe steel, having remarkably superior low temperature tenacity, by using steel, contained Mo, in stead of Nb of Nb contained steel as the line pipe steel for extremely cold region and rolling under a fixed condition after heating at a fixed temperature.

Manufacture of steel plate for line pipe remarkably superior in low temperature toughness rolled as it is

PURPOSE:To produce a high tensile steel sheet with excellent brittleness crack propagation resistance without adding expensive alloy elements by producing steel contg. C and Mn by a combination of hot rolling, low temp. rolling, and heating.

Production of high tensile steel sheet with excellent brittleness crackpropagation stopping properties

PURPOSE:Production of high tensile strength steel plate with high strength and bendability after rolling without any further working, and having sufficiently high toughness at weld after heavy heat-input welding(more than 50KJ/cm).

Process for producing high tensile strength steel plate with excellent weldability and bendability

PURPOSE:To prevent grain structure of rolled material from growing larger and to increase toughness in hot rolling of steel containing Mo, Ti, and B, V by treating the steel under specific onditions.

Masui Hiroaki

Papers

Manufacture of high tensile steel

Manufacture of steel plate for line pipe remarkably superior in low temperature toughness rolled as it is

Production of high tensile steel sheet with excellent brittleness crackpropagation stopping properties

Process for producing high tensile strength steel plate with excellent weldability and bendability

Production of high tensile strength steel excllent in weldability and sr brittleness resistance