The present invention provides an integrally cast excavator bucket and a manufacturing method thereof. The integrally cast excavator bucket comprises a lifting lug, a top plate, two side plates and a bottom plate connected with the two side plates. A method for manufacturing the integrally cast excavator bucket by adopting the cast steel comprises the following steps: putting cast steel components into a melting furnace, and carrying out modification treatment before furnace after melting is finished; manufacturing models and a template, coating, heating, vacuumizing, placing sandboxes, adding sand, molding, carrying out mold closing, casting, quenching, tempering and cooling to room temperature to finish casting of the excavator bucket. The integrally cast excavator bucket is formed by once casting from a low-alloy steel material by adopting a vacuum sealing technology, and is high in product strength, resistant to wear and corrosion, high in impact resistance and long in service life.

The present invention provides an integrally cast excavator bucket and a manufacturing method thereof. The integrally cast excavator bucket comprises a lifting lug, a top plate, two side plates and a bottom plate connected with the two side plates. A method for manufacturing the integrally cast excavator bucket by adopting the cast steel comprises the following steps: putting cast steel components into a melting furnace, and carrying out modification treatment before furnace after melting is finished; manufacturing models and a template, coating, heating, vacuumizing, placing sandboxes, adding sand, molding, carrying out mold closing, casting, quenching, tempering and cooling to room temperature to finish casting of the excavator bucket. The integrally cast excavator bucket is formed by once casting from a low-alloy steel material by adopting a vacuum sealing technology, and is high in product strength, resistant to wear and corrosion, high in impact resistance and long in service life.

A wear part includes a body and a cladding layer. The body includes an outer surface. The body is made from a base material. The cladding layer is connected to the outer surface of the body. The cladding layer is constructed with the body via additive manufacturing. The cladding layer is made from a surfacing material which is harder than the base material.

A wear part includes a body and a cladding layer. The body includes an outer surface. The body is made from a base material. The cladding layer is connected to the outer surface of the body. The cladding layer is constructed with the body via additive manufacturing. The cladding layer is made from a surfacing material which is harder than the base material.

A hot-rolled steel sheet has a predetermined chemical composition, a microstructure of an inner region includes 40% to 80% of one or two of martensite and bainite in total and 20% to 60% of ferrite by area ratio, an area ratio of a remainder in microstructure is less than 5%, s/c, which is a ratio of a ferrite area ratio s of a surface layer region to a ferrite area ratio c of the inner region, is in a range of 1.15 to 2.50, (1Hvs/Hvc), which is a hardness difference ratio between a Vickers hardness Hvs of the surface layer region and a Vickers hardness Hvc of the inner region, is 0.20 or less, and a tensile strength is 980 MPa or more.

A high-strength stainless steel seamless pipe for oil country tubular goods has a composition that comprises, in mass %, C: 0.002 to 0.05%, Si: 0.05 to 0.50%, Mn: 0.04 to 1.80%, P: 0.030% or less, S: 0.002% or less, Cr: more than 14.0% and 17.0% or less, Ni: 4.0 to 8.0%, Mo: 1.5 to 3.0%, Al: 0.005 to 0.10%, V: 0.005 to 0.20%, Co: 0.01 to 1.0%, N: 0.002 to 0.15%, and O: 0.006% or less, and that satisfies the predetermined formulae, and in which the balance is Fe and incidental impurities, the high-strength stainless steel seamless pipe having a microstructure containing prior austenite having an average grain size of 40 m or less, the high-strength stainless steel seamless pipe having a yield strength of 758 MPa or more.

A steel alloy with unique and superior combinations of properties such as elevated temperature strength, oxidation resistance, thermal conductivity and wear resistance. Disclosed embodiments comprise or substantially consist of: C in an amount of 0.2-0.45 weight %; Si in an amount of 0.6-1.1 weight %; Mn in an amount of 1.1 weight %; Cr in an amount of 2.5-4.0 weight %; one or both of Mo or W, a combined amount of the Mo or W0.9 weight %; Ti in an amount of 0.035-0.14 weight %; V in an amount of 0.18-1.1 weight % and the balance being Fe and usual impurities.

Embodiments of a method of heat treating a coiled tube, in particular coiled tubes for use in the oil and gas industry, and pipes produced from the methods. In particular, embodiments of the heat treating method can utilized tempering without bending in order to avoid the generation of subsequent defects.

Embodiments of a method of heat treating a coiled tube, in particular coiled tubes for use in the oil and gas industry, and pipes produced from the methods. In particular, embodiments of the heat treating method can utilized tempering without bending in order to avoid the generation of subsequent defects.

An object of the present invention is to provide a low thermal expansion cast steel having sufficient strength even at a high temperature and a low coefficient of thermal expansion. The low thermal expansion cast steel of the present invention is obtained by suitably heat treating a cast steel comprising, by mass %, C: 0 to 0.10%, Si: 0 to 1.00%, Mn: 0 to 1.00%, Co: 13.00 to 17.50%, Ni satisfying 3.5% Ni+118% Co3.5% Ni+121 (% Ni and % Co respectively represent the contents of Ni and Co (mass %)), and a balance of Fe and unavoidable impurities so that the 0.2% proof stress in a tensile test at 400 C. becomes 100 MPa or more, the average coefficient of thermal expansion at 25 to 350 C. becomes 6.0 ppm/ C. or less, and the Curie temperature becomes 350 C. or more.