TPT September 2015

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Zinc spray coating on ERW tube METALLIZING Equipment Co Pvt has supplied its complete automatic Zn spray-on coating for tube seams system to several well-known tube mills in India as well as to foreign territories. The manufactured arc spray system is easy to use and maintains a repeatable work quality. A roll-forming machine draws hot or cold rolled steel through successive stations and shapes the material into a tube. Electric resistance welding then closes the seam left by the butted edges. Although no filler metal is added that would change the chemical compositions, the welding process applies temperatures high enough to sacrifice some of the corrosion-resistant properties of the base metal. The process may also vaporise aluminium or galvanised coatings previously applied to the rolled steel. The thermal spray process applies a coating of zinc to reinstate the corrosion- resistance properties of the tubing. Applying the spray while the weld seam is hot assures a metallurgical bond of the sprayed material with the substrate, improves both the deposit efficiency and density of the sprayed material, and allows the coating to blend, thereby helping to hide the weld seam. Arc spray is one of the most user-friendly of the thermal or metal spraying processes used for applying metal coatings to base materials. Any electrically conductive material in wire form can be arc sprayed. Awire pulling system by DC motor, fitted in the gun, ensures precision wire-feed speed. The wires meet at the head of the gun and melt in the electrical arc. The molten mass is atomised and blown onto the substrate with compressed air. The particles cool to ambient temperature and coalesce into a high-quality metal coating. The distance from the arc to the tube seam is an important measurement on tube mill installations.

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Metallizing Equipment Co Pvt Ltd – India Website: www.mecpl.com

Messe Düsseldorf GmbH P.O. Box 101006

40001 Düsseldorf_Germany Tel. +49(0)211/4560-01 Fax +49(0)211/4560-668 www.messe-duesseldorf.de

Zn spray-on welded tube seam

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