Is stainless steel as good as poly lining and how does aluminium compare?
Stainless machines may be more expensive than poly and may be prone to cracking (recent cases in central NSW). In areas around Central Queensland where groundwater can chew CP&LM galvanising for breakfast, a number of large aluminium pivots have been installed and are successfully operating. Some manufacturers provide options with aluminium and some others with poly and others still PVC. Have your water quality assessed first before you start talking about alternate lining materials. A number of recent developments have used materials alternate to galvanised iron so as to ensure pipe integrity when using large quantities of fertiliser through the main pipeline. They chose to use alternate material because the growers wanted a 20-25 year life out of the machines. They will get it when they use these alternate materials. Most manufacturers have significant information on the effects of different quality issues on various materials that they use – if the local supplier is unsure of this i
