Double magnetic coupling for two welding heads that work parallel and independent at the front and at the back, (N) and (S), in paramagnetic and diamagnetic materials.

The present invention relates to an air conditioner. The air conditioner according to the present embodiment has a refrigeration capacity of 7 kW to 11 kW, inclusive, and uses a refrigerant R32 as a refrigerant, and since a refrigerant pipe therein is made of a ductile stainless steel material having 1% or less of a delta-ferrite matrix structure with respect to the grain size area thereof, and includes a suction pipe guiding the suction of the refrigerant into a compressor and having an outer diameter of 15.88 mm, the refrigerant pipe can maintain strength and hardness as good as or better than those of a copper pipe, while also maintaining good processability.

A stainless steel weldment and pad combined welding method includes steps of: (a) respectively processing and pairing butts of to-be-welded portions of two weldments, wherein, during pairing, inner walls of the two weldments are aligned at the same plane; the butts of the two weldments are opposed to form a V-shaped groove with an angle α; and between bottoms of the butts of the two weldments is kept a gap L of 2-4 mm; (b) providing a copper pad at the gap between the bottoms of the butts of the two weldments, wherein the copper pad closely attaches to the inner walls of the two weldments; (c) welding the V-shaped groove to form a root pass; and (d) removing the copper pad, and filling the root pass to be welded into a cover pass.

A process is provided for the continuous production of thin-walled, radially closed hollow profiles composed of nonferrous metals and having a small cross section comprises supply of a flat strip of the metal to a forming apparatus at a first supply speed, the thickness of the strip corresponding to the wall thickness of the hollow profile. The forming apparatus continuous forms the flat strip into a shape corresponding to the hollow profile. After forming, two opposite edges of the flat strip rest flush against one another in a contact region and are continuously welded by means of a laser which emits light having a wavelength of less than 600 nm. The laser heats an area in a welding region having a diameter of less than 20% of the cross-sectional dimension of the hollow profile. The welded hollow profile is taken off from the welding region and taken up in an uptake device.

A carrier component for a vehicle application, formed by two half-shells that are welded to one another at contact sides. When assembling the two half-shells for joining same at the contact sides, in a position in which the two half-shells are arranged above one another, the point of contact of the lower half-shell protrudes in relation to the external closed side of the other half-shell. The point of contact of one of the two half-shells protrudes inward in relation to the internal closed side of the other half-shell. A method for producing a carrier component from two half-shells is also disclosed.

The present invention relates to an air conditioner. The air conditioner according to the present embodiment has a refrigeration capacity of 11 kW to 16 kW, inclusive, and uses R32 as a refrigerant circulating therein, and since a refrigerant pipe therein is made of a ductile stainless steel material having 1% or less of a delta-ferrite matrix structure with respect to the grain size area thereof, the refrigerant pipe can maintain strength and hardness as good as or better than those of a copper pipe, while also maintaining good processability.

The present invention relates to an air conditioner. The air conditioner according to the present embodiment has a refrigeration capacity of 7 kW to 11 kW, inclusive, and uses, as a refrigerant, a mixed refrigerant containing 50% or more of R32, and since a refrigerant pipe therein is made of a ductile stainless steel material having 1% or less of a delta-ferrite matrix structure with respect to the grain size area thereof, and includes a suction pipe guiding the suction of the refrigerant into a compressor and having an outer diameter of 15.88 mm, the refrigerant pipe can maintain strength and hardness as good as or better than those of a copper pipe, while also maintaining good processability.

A method for producing a steel material for line pipes which has a tensile strength of 570 MPa or more, a compressive strength of 440 MPa or more, and a thickness of 30 mm or more, the method including heating a steel having a specific composition to a temperature of 1000° C. to 1200° C.; performing hot rolling such that a cumulative rolling reduction ratio in a non-recrystallization temperature range is 60% or more, a cumulative rolling reduction ratio in a temperature range of (a rolling finish temperature +20° C.) or less is 50% or more, and a rolling finish temperature is the Ar.sub.3 transformation point or more and 790° C. or less; and subsequently performing accelerated cooling from a cooling start temperature of the Ar.sub.3 transformation point or more, at a cooling rate of 10° C./s or more, until the temperature of a surface of a steel plate reaches 300° C. to 500° C.

Hot-rolled steel sheet having a chemical composition including, in mass %, C: 0.02 to 0.20%, Si: 0.01 to 1.50%, Mn: 0.10 to 3.00%, P: 0.10% or less, S: 0.010% or less, Al: 0.005 to 0.100%, Ti: 0.02 to 0.20%, N: 0.001 to 0.010%, Cu: 0 to 0.50%, Ni: 0 to 0.50%, Cr: 0 to 1.00%, Mo: 0 to 0.40%, Nb: 0 to 0.060%, V: 0 to 1.00%, B: 0 to 0.0100%, Ca: 0 to 0.0050%, O: 0.0100% or less, and the balance: Fe and impurities; in which: a steel micro-structure includes, in area %, ferrite: 60 to 80%, and a total of ferrite and bainite: 90% or more; an average of the crystal grain size of ferrite and bainite is 7.0 μm or less, a standard deviation of the crystal grain size is 2.0 or less; and a standard deviation of a diameter of Ti carbo-nitrides is 10 nm or less.

A method for limiting fitting distortion when welding a fitting to an in-service pipeline—where the fitting includes a thick, longitudinally extending, seam located between fitting halves—involves welding, on each side of the fitting, a middle third section of the seam in a pyramid-like fashion using an inward progression starting from an end of the middle third section along a profile of a seam bevel, and welding outer third sections of the seam using an outward progression from an end adjacent to the middle third section along a profile of the seam bevel. The welding of each of the three sections per side includes a temper bead welding technique of at least two layers to provide stress relief in lieu of traditional post weld heat treatment.