A method of forming a heat exchanger tube, particularly suited for condensing applications, contemplates cold-rolling a metallic strip to emboss a hydrophobic surface texture, to thereby form an embossed surface on the metallic strip. The method includes roll forming the metallic strip to a tubular shape, with the embossed surface on the exterior of the tubular shape, and welding the edges of the roll-formed strip to form a heat exchanger tube. Cold-rolling to emboss a hydrophobic surface texture exhibiting a contact angle of at least about 75° is contemplated, with processing including heat-treatment to minimize degradation of the hydrophobic surface texture, and roll-forming to avoid deformation of the hydrophobic surface texture,

A system for manufacturing hollow tubular jewellery comprises a die and core assembly for extruding a hollow metallic tube, wherein a core is positioned within a die of the die and core assembly to define three-dimensional surfaces or curved surfaces of a hollow metallic tube. A mandrel is provided for bending the hollow metallic tube, wherein the mandrel is fixed proximal from the die and core assembly. A laser source is provided, which is configured to emit a laser beam to form perforations on the hollow metallic tube. The system includes a fixture which is adapted to hold the hollow metallic tube. The fixture is configured to rotate and tilt to adjustably position a three-dimensional surface or curved surface of the hollow metallic tube perpendicular to the laser beam for forming perforations.

An electric resistance welded steel pipe for manufacturing a hollow stabilizer has a Rankford value in a pipe longitudinal direction of from 0.7 to less than 1.0. The electric resistance welded steel pipe is subjected to cold bending and then to a heat treatment including quenching and tempering to manufacture a stabilizer. The cold bending is cold rotary draw bending. When bent with a bend radius of from 1.0 times to 3.0 times an outer diameter of the pipe before cold bending, a flattening ratio is from 0% to 10%, a thickness reduction rate on a bending outside and a thickness increase rate on a bending inside are from 0% to 10%, and additionally, a circumferential length change of a bending center portion is from 0% to 10%. A Vickers hardness of the stabilizer after the heat treatment is adjusted to from 400 HV to less than 580 HV.

The present invention relates to an absorption chiller which comprises an evaporator, an absorber, a regenerator and a condenser and has an absorbing solution and a refrigerant circulating. A heat transfer pipe, which is provided on one or more of the evaporator, absorber, regenerator and condenser, is comprised, and a ductile stainless steel pipe, which has 1% or less of delta ferrite matrix structure on the basis of the grain size area, is applied to the heat-transfer pipe. Therefore, copper-level flexibility can be obtained in comparison with an existing stainless steel pipe.

The invention relates to long-dimensional flexible tubes (coiled tubing). There are several variants of the proposed basic pairs of an umbilical coiled tubing and include means of their production with multi-stage sequential shaping process of one or multiple strips at an estimated geometry, and where isolated channels, partitions and flanges are formed during this process. If required, longitudinal butts of an additional shaped longitude strips can be welded to them to form additional hydraulic channels of the umbilical coiled tubing which can be reeled up to a drum. Other types of service channels (electric, fiber-optic, capillary etc.) or standard coiled tubing can be placed inside or outside channels in the form of a service channels tape. Flanges located beyond the outside dimensions of an umbilical coiled tubing may have a wave-type of form. Connecting partitions may have holes intended for fingers of injector, for elevator, for service channels tape. Flanges and partition holes are weight-carrying members of umbilical coiled tubing. Welding seams, flanges, centers of a closed channels and partitions are located, mainly, on the middle line of an umbilical coiled tubing's cross-section. The umbilical coiled tubing makes it possible to significantly increase possibilities of coiled tubing units in technological operations as well as in artificial lift methods due to its multi-channel design and, consequently, multifunctionality.

A system for manufacturing hollow tubular jewelery is disclosed. It comprises die and core assembly for extruding hollow metallic tube, wherein core is positioned within die of die and core assembly to define three-dimensional surfaces or curved surfaces of hollow metallic tube. Mandrel is provided for bending hollow metallic tube, wherein mandrel is fixed proximal from die and core assembly. A laser source is provided, which is configured to emit laser beam to form perforations on hollow metallic tube. The system includes fixture which is adapted to hold hollow metallic tube. Fixture is configured to rotate and tilt to adjustably position three-dimensional surface or curved surface of hollow metallic tube perpendicular to laser beam for forming perforations. This helps in overcoming challenge of perforating unconventionally angled tubes at different angles.

What is provided is an electric resistance welded steel pipe manufacturing device that is configured to perform welding while forming a strip-shaped steel sheet in a tubular shape and supplying a plasma flow to a pair of abutment end surfaces to perform shielding. The electric resistance welded steel pipe manufacturing device includes a mandrel; and a plasma flow feeder that is provided in the mandrel to supply the plasma flow.

Changing of a horizontal roll in a horizontal roll stand involving readjustment of an amount of pressing is to be done readily and promptly. In order to achieve this, a horizontal roll stand 10 with a pair of built-in upper and lower horizontal rolls 11 is configured to retreat toward one side across a forming line. A fixed stand 40 stands upright on a counter-retreating side of the forming line. An overhang part 42 of the fixed stand 40 jutting out over the forming line is provided with a pressure device 43 that applies a pressing force to the horizontal rolls 11. The horizontal roll stand 10 includes a horizontal roll housing 12 with an opened top, receives the pressing force from the pressure device 43 via the opened top, and retreats to the outside of the forming line while the pressure device 43 is left on the forming line. The overhang part 42 of the fixed stand 40 is engaged with the horizontal roll housing 12 of the horizontal roll stand 10 to support the horizontal roll housing 12 in the forming line.

The present invention provides an integrated method for forming and performance control of NiAl alloy thin-walled tubular parts. A Ni/Al laminated foil tube is obtained after Ni foils and Al foils are alternately laminated and coiled; and the Ni/Al laminated foil tube is subjected to plastic forming, reaction synthesis and densification treatment in a gas bulging forming die to obtain a NiAl alloy thin-walled tubular part. The present invention solves the problem in the prior art that the preparation of an existing NiAl alloy sheet and the formation of the thin-walled tubular part from the sheet feature difficulty in material flow and structural performance control and a complicated process. Data of embodiments shows that the NiAl alloy thin-walled tubular parts obtained by using the method of the present invention has a high forming rate, high dimensional precision, uniform composition distribution, good tubular part compactness and no defects on the surface.

The disclosure relates to a method for pre-shaping sheet metal (1) in strip- or panel-form having a flat cross-sectional profile into a circular arc-shaped cross-sectional profile, in a pre-shaping section (3) of a plant for producing open-seam pipes. The circular arc-shaped cross-sectional profile is provided to the sheet metal (1) in the pre-shaping section (3) by means of roll profiling in a plurality of successive bending steps in a transport direction. The cross-sectional profile is created by step-by-step bending of individual circular arc portions (8) from an outer edge of the sheet metal (1) toward a center line (7) such that the individual circular arc portions (8) directly adjoin one another or at least partially overlap. The disclosure further relates to a device for carrying out the method.