Tube forming methods can be used for efficient transition in the production of tubes having varying thickness. Material used to form consecutive tubes may have the same thickness along a separation plane separating a first discrete section from a second discrete section of the material, and the first discrete section and the second discrete section may each have varying thickness in a feed direction of the material. With such a thickness profile, the first discrete section of the material may be formed into a first cylinder having varying thickness and separated from the second discrete portion as the second discrete section is formed into a second cylinder having varying thickness. In particular, the transition between the first cylinder and the second cylinder may be achieved without scrap and/or interruption, resulting in cost-savings and improvements in production throughput associated with forming tubes having varying thickness.

A double-wall spiral welded pipe includes a first steel belt layer and a second steel belt layer which have equal widths, are arranged in parallel and align with each other; at least two supporting steel bars perpendicular to the first steel belt layer and the second steel belt layer are arranged between the first steel belt layer and the second steel belt layer; the supporting steel bars are arranged on end parts of two sides of the first steel belt layer and the second steel belt layer and extend together with the first steel belt layer and the second steel belt layer; and the first steel belt layer, the second steel belt layer and the supporting steel bars on the end parts of the two sides are mutually welded to form a double-layer composite steel belt with a rectangular section in an extending direction.

A high temperature iron-chromium-aluminium (FeCrAl) alloy tube extending along a longitudinal axis, wherein the tube is formed from a continuous strip of a high temperature FeCrAl alloy and comprises a helical welded seam. The high temperature FeCrAl alloy tube is manufactured by feeding a continuous strip of the high temperature FeCrAl alloy toward a tube shaping station, helically winding the strip such that long edges of the strip abut each other and a rotating tube moving forward in a direction parallel to its longitudinal axis is formed, and continuously joining said abutting long edges together in a welding process directly when the tube is formed, whereby a welded tube comprising a helical welded seam is obtained.

A high temperature iron-chromium-aluminium (FeCrAl) alloy tube extending along a longitudinal axis, wherein the tube is formed from a continuous strip of a high temperature FeCrAl alloy and comprises a helical welded seam. The high temperature FeCrAl alloy tube is manufactured by feeding a continuous strip of the high temperature FeCrAl alloy toward a tube shaping station, helically winding the strip such that long edges of the strip abut each other and a rotating tube moving forward in a direction parallel to its longitudinal axis is formed, and continuously joining said abutting long edges together in a welding process directly when the tube is formed, whereby a welded tube comprising a helical welded seam is obtained.

A helicoid conveyor screw manufactured from alloy steel and tempered by electromagnetic induction or flame used to convey abrasive granular products in the process of screw rotation under high friction and wear. Its inventive principle is related to the method for obtaining it by alloying steel with the chemical element Boron (B) and heat treating it, which results in greater hardness and durability of the flight.

A control system for forming a tapered structure includes a sensor providing feedback for a machine for forming a tapered structure including at least three rolls having at least one bend roll and at least two guide rolls. The guide rolls may include rollette banks having a plurality of rollettes. The machine may also include an adjustment mechanism to position at least one of the rolls, where a diameter of the tapered structure being formed is controlled by relative positions of the rolls. The machine may also include a joining element to join edges of a stock of material together as it is rolled through the rolls to form the tapered structure. The control system may also include a controller to receive feedback from the sensor and to send a control signal based on the feedback to the adjustment mechanism for positioning at least one of the rolls.

A jacketed vessel for temperature control of contents within the vessel is provided. The vessel has a shell and an external jacket through which heating or cooling fluid is circulated. The jacket is formed by a length of conduit arranged in a spiral orientation around the vessel shell. The conduit has a center portion having a concave inner surface and has opposing side portions having convex inner surfaces. Edge sections of each side portion are welded to the exterior surface of the shell to form the jacket. Edge sections of adjacent arcs of conduit may be simultaneously welded to the shell in a single weld pass. The shape of the conduit provides improved heat transfer and pressure drop characteristics, as well as improvements in the vessel manufacturing process.

A method for designing an additively-manufactured object includes: a slicing step of slicing a shape of the additively-manufactured object into weld bead layers each having a height corresponding to one bead layer using data of the shape of the additively-manufactured object, thereby generating a plurality of virtual bead layers; a reference direction setting step of setting, as a reference direction, a direction in which the sliced layer of the additively-manufactured object is continuously provided and extended in an intermediate layer disposed at a deposition-direction center of the plurality of virtual bead layers; and a bead adjusting step of adjusting a bead size of the weld bead to be formed in the plurality of virtual bead layers depending on a bead shape in a section perpendicular to the reference direction.

A high temperature iron-chromium-aluminium (FeCrAl) alloy tube extending along a longitudinal axis, wherein the tube is formed from a continuous strip of a high temperature FeCrAl alloy and comprises a helical welded seam. The high temperature FeCrAl alloy tube is manufactured by feeding a continuous strip of the high temperature FeCrAl alloy toward a tube shaping station, helically winding the strip such that long edges of the strip abut each other and a rotating tube moving forward in a direction parallel to its longitudinal axis is formed, and continuously joining said abutting long edges together in a welding process directly when the tube is formed, whereby a welded tube comprising a helical welded seam is obtained.

A control system for forming a tapered structure includes a sensor providing feedback for a machine for forming a tapered structure including at least three rolls having at least one bend roll and at least two guide rolls. The guide rolls may include rollette banks having a plurality of rollettes. The machine may also include an adjustment mechanism to position at least one of the rolls, where a diameter of the tapered structure being formed is controlled by relative positions of the rolls. The machine may also include a joining element to join edges of a stock of material together as it is rolled through the rolls to form the tapered structure. The control system may also include a controller to receive feedback from the sensor and to send a control signal based on the feedback to the adjustment mechanism for positioning at least one of the rolls.