Provided is an electrical dust-collecting filter manufacturing method and an electrical dust-collecting filter. The method includes the steps of: preparing a frame body, a dust-collecting electrode, a discharge electrode, and a discharge frame; assembling the dust-collecting electrode into an assembly hole of the frame body; connecting the discharge frame to the frame body via an insulating member; and arranging the discharge electrode in an axial direction inside the dust-collecting electrode via the discharge frame and fixing the same. The dust-collecting electrode assembling step includes: temporarily elastically deforming the dust-collecting electrode in the radial direction and inserting the same into the assembly hole of the frame body; and pressurizing end parts of both ends of the dust collecting electrode, which protrude out of a plate member when fitted into the assembly hole, in the axial direction such that the end parts are compressed against the surface of the plate member.

Disclosed is a tubular core on which sheets of metal or other material can be wound and supported, for shipment, handling and dispersal, and a method for forming the core. The core comprises a metal sheet or strip which has a rectangular-ribbed cross-sectional profile of flattened ribs, and which is wound spirally into a tubular configuration. The core is formed by passing the strip through a plurality of roll-forming stands, to initiate forming and progressively form an arcuate ribbed sinusoidal profile, then a final roll-forming pass is used (or several such passes are used) to flatten the ribs of the profile so that the rectangular flattened ribs collectively form a support surface for the sheets which are wound and supported on the core.

A method for manufacturing a refrigerant guide tube of a heat exchanger and a refrigerant guide tube manufactured using the method and a heat exchanger with the refrigerant guide tube are disclosed. The refrigerant guide tube includes tube body and channels extending through a wall of the tube body. The tube body is formed by a butt joint of side edges of more than one bar-shaped plate materials along the length direction. The method allows forming the refrigerant channels of the guide tube before or during forming the tube body when the method is used to manufacture the guide tube, so as to avoid directly forming the channels on the tube body and make the process of manufacture the guide tube simpler and more convenient.

An apparatus for producing a tailored sheet metal strip, comprising at least one welding station, by means of which at least two sheet metal strips can be welded to one another along their longitudinal edges, and at least two strip feeding devices for respectively feeding one of the sheet metal strips into the at least one welding station, wherein the at least two strip feeding devices and the at least one welding station define a production line. A further-processing station for further processing is integrated in the production line downstream of the at least one welding station in the strip running direction and is equipped with tools for applying reinforcing material, to local points of at least one of the sheet metal strips which are connected to one another, for punching holes and/or for forming at least one of the sheet metal strips which are connected to one another.

An apparatus for producing a tailored sheet metal strip, comprising at least one welding station, by means of which at least two sheet metal strips can be welded to one another along their longitudinal edges, and at least two strip feeding devices for respectively feeding one of the sheet metal strips into the at least one welding station, wherein the at least two strip feeding devices and the at least one welding station define a production line. A further-processing station for further processing is integrated in the production line downstream of the at least one welding station in the strip running direction and is equipped with tools for applying reinforcing material, to local points of at least one of the sheet metal strips which are connected to one another, for punching holes and/or for forming at least one of the sheet metal strips which are connected to one another.

Provided are a welded titanium tube capable of improving heat-transfer performance and detecting surface defects and a manufacturing method therefor. The welded titanium tube is formed of a tubular-shaped titanium plate, whose edges are butt-welded. The welded titanium tube includes an outer peripheral surface and an inner peripheral surface, at least one of which is provided with a concavo-convex pattern including a base surface and a plurality of protrusions. A mean maximum height of the protrusions is in the range of 12 to 45 m. A ratio of a maximum value to a mean pitch of the protrusions is less than 2. A ratio of a mean maximum dimension of the protrusions to the mean pitch is 0.90 or less, and a ratio of the mean maximum height to a wall thickness is 0.11 or less.

In a method for the production of a heat exchanger, a turbulator insert is placed into a heat exchanging tube, with the turbulator insert having a solder applied thereon in at least one region. Weld spots using resistance welding are formed on an inner surface of the heat exchanging tube with the turbulator insert, and the inner surface of the heat exchanging tube is interlinked with the turbulator insert through brazing.