18:25 Jul 4, 2008
Achei o significado no Wikepedia como mostrado abaixo...só não sei o termo em português...
A wellhead is collection of equipment that exists atop (the exposed area above ground) an oil or gas well. It is commonly made up of valves, fittings, piping, gauges, and flanges. Its purpose is to allow access to the wellbore in a controlled fashion, in order to inject chemicals or fluids, and to allow the flow of oil or gas to be directed as it is produced. Within the wellhead, inside the tubing hanger flange, is the tubing hanger (commonly referred to as a "dog nut"), from which the production tubing hangs.
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