Abstract: A powdery fuel combustion apparatus disposed on furnace side plane (7) of vertical square body type furnace in which a vertical plane passing through a fuel jetting directional axis (8) does not cross the furnace side plane orthogonally, and thus the workability of furnace wall tubes and burner panel, and the maintainability of burner nozzle are improved. The apparatus includes a burner nozzle (1) that is formed such that the nozzle has right and left non-symmetrical shapes, with respect to a vertical plane passing through axis (8). Also, the nozzle has a tip portion opening lying in an opening plane (2) which coincides or is parallel to the furnace side plane (7).

Abstract: A high strength, low alloy, heat resistant steel having excellent weldability has an average crystal grain diameter of at most 110 &mgr;m and consists essentially of, by mass %: C: 0.03-0.15%, Si: at most 1%, Mn: at most 2%, P: at most 0.03%, S: at most 0.03%, Ni: at most 0.5%, Cu: at most 0.5%, Cr: 1.8-2.8%, V: 0.1-0.3%, Nb: 0.01-0.08%, Mo: 0.05-0.35%, W: 1.2-1.8%, Ti: 0.001-0.05%, B: 0-0.02%, Al: at most 0.1%, O: at most 0.1%, N: in an amount satisfying the formula [%N]≦[%Ti]+5[%B]+0.004, and a remainder of unavoidable impurities.

Abstract: This invention provides a welding material for low chromium (Cr) ferritic heat-resisting steel having high toughness, wherein the chemical composition of welding metal comprises, in weight %, carbon (c) 0.04-0.1%, silicon (Si) 0.1-0.6%, manganese (Mn) 0.1-0.6%, phosphorus (P) 0.0005-0.03%, sulfur (S) 0.0005-0.015%, chromium (Cr) 1.75-2.5%, nickel (Ni) 0.01-0.8%, molybdenum (Mo) 0.05-1.5%, vanadium (V)0.01-0.5%, tungsten (W) 0.05-2%, niobium (Nb) 0.01-0.2%, tantalum (Ta) 0.01-0.5%, aluminum (Al) 0.003-0.05%, boron (B) 0.0001-0.01%, nitrogen (N) 0.003-0.03%, and the remainder comprises iron and inevitable impurities. The welding material satisfies the following formula: C+Cr/20+Mo/15+V/10+W/7+5B.ltoreq.0.8%. According to this invention, the welding material is suitable for welding low Cr ferritic heat-resisting steels having high strength such as those used in steam generators and heat exchangers of boilers, etc.

Abstract: This invention provides low-Cr ferritic steels and low-Cr ferritic cast steels having excellent high-temperature strength and weldability. These low-Cr ferritic steels and low-Cr ferritic cast steels consist essentially of, on a weight percentage basis, 0.03 to 0.12% C, 0.05 to 0.7% Si, 0.05 to 1% Mn, 0.002 to 0.025% P, 0.001 to 0.015% S, 0.3 to 3% Cr, 0.01 to 1% Ni, 0.05 to 3% Mo, 0.01 to 0.5% V, 0.1 to 3% W, 0.01 to 0.2% Nb, 0.02 to 1.5% Re, 0.003 to 0.05% Al, 0.0001 to 0.01% B, 0.003 to 0.03% N, and the balance being Fe and incidental impurities, and have excellent high-temperature strength and weldability.

Abstract: A low Mn-low Cr ferritic heat resistant steel consisting essentially of, in weight %: 0.02-0.20% C, up to 0.7% Si, less than 0.1% Mn, up to 0.8% Ni, 0.8-3.5% Cr, 0.01-3.0% W, 0.1-0.5% V, 0.01-0.20% Nb, 0.001-0.05% Al, 0.0005-0.05% Mg, 0.0005-0.01% B, less than 0.05% N, up to 0.03% P, up to 0.015% S, 0.001-0.05% Ti and the balance Fe and incidental impurities, wherein the B content is defined so as to satisfy the following formula (14/11)B>N-N(V/51)/{(C/12)+(N/14)}-N(Nb/93)/{(C/12)+(N/14)}-N(Ti/48)/{C/12 )+(N/14)}. The steel can further contain optionally 0.01-1.5% Mo, and/or one or more elements selected from the group consisting of 0.01-0.2% La, 0.01-0.2% Ce, 0.01-0.2% Y, 0.01-0.2% Ca, 0.01-0.2% Ta and 0.01-0.2% Zr. The steel can be used in place of the austenitic steels or high Cr ferritic steels, since it has remarkably improved toughness, workability and weldability, and excellent creep properties at elevated temperatures.

Abstract: A low-Cr ferritic steel with improved toughness as well as creep strength is disclosed, which consists essentially of, by weight %:C: 0.03-0.12%, Si: 0.70% or less, Mn: 0.10-1.50%,Ni: 2.0% or less, Cr: 1.50-3.50%, W: 1.0-3.0%,V: 0.10-0.35%, Nb: 0.01-0.10%,B: 0.00010-0.020%, N: 0.005% or less,Al: 0.005% or less,Ti: not less than 0.001% but less than 0.05%,Cu: 0.10-2.50%,at least one of La, Ce, Y, Ca, Zr, Ta each in an amount of 0-0.20%, and Mg in an amount of 0-0.05%,Mo in an amount of 0-0.40%, anda balance of Fe and incidental impurities including P: not more than 0.030% and S: not more than 0.015%.

Abstract: A Cu-containing, high-Cr ferritic, heat-resistant steel is prevented from copper checking without a reduction in strength, toughness, resistance to hot corrosion, or oxidation, and its weldability is maintained at satisfactory levels. The steel consists essentially, on a weight basis, of: C: 0.03-0.15%, Si: at most 0.7%, Mn: 0.1-1.5%, Ni: 0.05-1.0%, Cr: 8-14%, W: 0.8-3.5%, V: 0.1-0.3%, Nb: 0.01-0.2%, N: 0.001-0.1%, Al: at most 0.05%, Cu: 0.4-3.5%, B: 0-0.02%, one or more elements selected from the group consisting of La, Ce, Ca, Y, Ti, Zr, and Ta: 0-0.2% each, and a balance of Fe and incidental impurities, wherein the Cu and Ni contents satisfy the following Inequality: 2.5.ltoreq.(%Cu)/(%Ni).ltoreq.4.5.

Abstract: A low-alloy steel consists essentially, on a weight basis, of: C: 0.03-0.12%, Si: at most 0.7%, Mn: 0.1-1.5%, Ni: at most 0.8%, P: at most 0.03%, S: at most 0.015%, Cr: 1.5-3.5%, W: 1-3%, V: 0.1-0.35%, Nb: 0.01-0.1%, B: 0.0001-0.02%, N: less than 0.005%, Al: less than 0.005%, Ti: 0.001-0.1%, optionally one or more elements selected from the group consisting of: La, Ce, Y, Ca, Zr, and Ta: 0.01-0.2%, Mg: 0.0005-0.05%, and Mo: 0.01-0.4%, and a balance of Fe and incidental impurities, wherein the Ti and Ni contents satisfy the following inequality:0.080.gtoreq.Ti(%)-(48/14).times.N(%).gtoreq.0.003.The steel has improved creep strength at high temperatures and improved toughness. It can be substituted for expensive austenitic stainless steels or high-Cr ferritic steels.

Abstract: A support structure supports a fluidized bed firing boiler disposed within a cylindrical pressure vessel and operated while the inside of a fluidized bed furnace is kept pressurized. A main body of the pressure fluidized bed firing boiler disposed within the pressure vessel is divided into a suspended section suspended from a support beam disposed at an upper interior portion within the pressure vessel, and a bottom-supported section supported by a support beam disposed at a lower interior portion of the pressure vessel. Also, a metallic expansion joint in the form of an undulated plate is provided at a point of engagement between the suspended section and the bottom-supported section.