Galvanised Mild Steel Pipe
Galvanised Mild Steel Pipe
(OP)
Galvanised mild steel pipe with screwed or flanged connections is used extensively in developing countries for water supply transmission pipelines and distribution systems. Often it achieves service lives of little over 10 to 15 years. When whole life costs are comapred with more durable materials then it can be shown to be more expensive. However, when you have limited funds you consider only what you have to pay out now not what may nedd to be paid out in 10 years time. I am looking for arguments to support my case for using more durable materials (ductile iron, PVC, GRP (FRP) etc). - any papers on the performance of galvanised mild steel pipe and its suitability (unsuitability) for potable water supplies.





RE: Galvanised Mild Steel Pipe
RE: Galvanised Mild Steel Pipe
A lot will depend on the size of the piping and thickness of plastic to be used, is it going to be buried, is it going to be in harms way where it could be easily damaged by heavy equipment or personnel, is the location a safe one so as not to cause colatteral damage if it is broken, what about having to support it in long runs?
What are water composition and temp as this could have a seriuos effect on corrosion of the metal used. Usually pitting and/or under deposit corrosion will occur which are the worst types so that average corrosion rates of the particular material in that service would not be useful for determing it's life.
RE: Galvanised Mild Steel Pipe
I'm sure not aware that galvanized pipe would have service life of 10-15 years, though- that sounds awfully low. Isn't this what's been used in houses extensively?
I'm not aware of anything besides PVC really being competitive in the sizes that galvanized pipe is normally used in (2" or less).
RE: Galvanised Mild Steel Pipe
Brian
RE: Galvanised Mild Steel Pipe
Zambo
RE: Galvanised Mild Steel Pipe
ABS has been used in exposed environments for over thrity five years. It has a greater fracture toughness than PVC-U. It is cost competitive. The product is manufactured by Tyco, Georg Fisher or Durawills. It is also used extensively for pure water in the electronics field.
Its toughness and resistance to UV allows its use in above ground applications.
RE: Galvanised Mild Steel Pipe
RE: Galvanised Mild Steel Pipe
Vita sine litteris mors est.
RE: Galvanised Mild Steel Pipe
From my experience the reasons GI is used is simple, availability. When I arrived in Hong Kong (from UK) I was shocked to find that GI was used for everything! potable water chilled water, everything was GI. Primarily because that was all that was available and the importers didnt want to gamble buying the new fangled copper and plastic's since none of the fitters knew how to install it.
Thankfully that has all changed, with copper and plastic potable water is commonplace. However, the old GI handover continues, we have GI covered pvc here, yup, a perfectly good pvc pipe inside within a GI pipe.
Anyway to answer the OP, if the market conditions i.e. dealers stock the material , and provide the necessary support i.e. warantee, tools, etc. you too amy get mdpe.
Locally two factors effected change, change in regulations and a large utility started installing mdpe mains. And I agree if you install GI today, they will be replacing the mains again very soon.
RE: Galvanised Mild Steel Pipe
also you don't only get low cost and low spec pipes from India and China. they are cheap because the production cost are are low in India and China. you do have a minimum standard below which you cannot go and those things are adhered in all the water supply Projects.
RE: Galvanised Mild Steel Pipe
RE: Galvanised Mild Steel Pipe
It is comparable in cost to GI.
The tradesmen in SE Asia are just as capable of learning new techniques as other countries. The assumption that they are some way inferior and incapable is offensive. Look at many of your building sites in so called developed world and it will be tradesmen from these very countries.
Let engineeers educate the World Bank on sustainability. It takes six times as much energy to produce GI as it does ABS. What does that do for global warming?
Let the engineering institutues and standards bodies in the developed world encourage the use of ISO standards in less developed countries.
Give a man a fish and he has a meal for the night. teach him how to fish and he will have a feed forever. Invest & teach him how to build a fish farm and he will have a thriving business, feed the community and challenge the big companies in the developed world.
Perhaps thats what the western world is a fraid of doing!
RE: Galvanised Mild Steel Pipe