The Introduction of ERW Galvanized Steel Pipe
What is ERW steel pipe? For pipes 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 Pipe.
ERW galvanized steel pipes has long been one of the most used building materials in the world. ERW galvanized steel pipes can resist the attack of wild, water & road salts. ERW steel pipes are used in Water Pipelines, Agriculture and Irrigation (Water Mains, Sewerage Systems, Industrial Water Lines, Plant Piping, Deep Tube-Wells & Casing Pipes). Other popular application area includes usage in gas pipe lines (pipe lines for natural gas, LPG and other non-toxic gases).
ERW galvanized steel pipe is steel pipe covered with a protective coating of zinc that greatly reduces its tendency to corrode and extends its life expectancy. It may be used in residential water supply lines, but not gas lines because natural gas causes the zinc to flake off and clog the system. It's not frequently used for water supply lines because the minerals in the water react with the galvanizing material and form scale, which builds up over time and will eventually clog the pipe. ERW galvanized steel pipe during galvanizing, steel is immersed in a molten zinc bath, ensuring a tough, uniform barrier coating. Zinc’s natural corrosion resistance provides long-term protection, even in outdoor environments. Apart from preventing water corrosion, it is also equally effective in dry & indoor environments.
The fitting for ERW galvanized steel pipe is galvanized malleable (soft) cast iron. They connect by screwing onto the threaded pipe, after applying a small amount of pipe joint compound on the threads. Larger diameter pipe is welded rather than threaded.