Application: Used for transporting low pressure liquid, gas and heating.
Specification: OD: 21.3mm ~ 406.4mm
WT: 0.5mm ~ 20mm
LENGTH: 0.3mtr ~ 18mtr, Ramdon Length, Fixed Length, SRL, DRL
Standard and Grade: GB/T 3091 Q195/Q215/Q235/Q345,ASTM A53, BS 1387, JIS G3444 STK400/STK500, EN 39, EN 1139 S235JR/S275JR, EN 10025, EN 10219
Pipe Type: Seamless & Welded Steel Pipe (Round/Square/Rectangular)
End: Square Cut/Threaded, Burr Removed
Zinc Coating: 120~500 g/m2 （30um~70um）
Packing: Steel Strips bundled, Plastic Caps plugged, Waterproof Paper wrapped etc.
What is hot dip galvanized pipe?
Hot dip galvanized pipe is molten matrix metal and the reaction of the iron alloy layer, so that the substrate and coating combination of both. Hot dip galvanized pipe is first pickled, the steel surface in order to remove iron oxide, after pickling, by mixing the aqueous solution tank for cleaning solution or ammonium chloride or zinc chloride, and then into hot-dip plating bath.
Hot-dip galvanizing involves three main steps:
Preparation: The galvanizing reaction will only occur on a chemically clean surface, so the first step of the process involves removing contamination. First, the metal is degreased using a caustic solution and then dipped in hydrochloric acid to remove rust, mill scale, welding slag, paint and grease. This followed by a rinse and a dip in a flux solution, which is usually about 30 percent zinc ammonium chloride.
Galvanizing: When the clean iron or steel component is dipped into the molten zinc (at 842°F (450°C)), zinc-iron alloy layers form as a result of a metallurgical reaction between the iron and zinc. When the material is pulled from the galvanizing bath, a layer of molten zinc is present on top of the alloy layer. When it cools, it has the bright, shiny appearance associated with galvanized products.
Inspection: After galvanizing, the coated materials are inspected for coating thickness and coating appearance. A variety of simple physical and laboratory tests may be performed to determine thickness, uniformity, adherence and appearance of the zinc coating.
Steel Pipes manufacturers and Exports huge range of Hot dip Galvanized Steel Tubes & Steel Pipes. For pipes or tubes size 4 inch (10.2mm) OD and below, strip is fed into a set of forming rolls which consists of horizontal and vertical rollers so placed as to gradually from the flat strip in to a tube which is then allowed to pass the welding electrodes. The electrodes are copper disks connected to the secondary of a revolving transformer assembly. The copper disk electrodes make contact on each side of the seam and temperature is raised to the welding point. Outside flash is removed by a cutting tool as the tube leaves the electrodes, inside flash is removed either by an air hammer or by passing a mandnel through the welded tube after the tube has been cooled. This is termed as Electric Resistance Welded or galvanized tube/pipe.
