The speed (usually an average) with which corrosion progresses (it may be linear for a while); often expressed as though it were linear, in units of mdd (milligrams per square decimeter per day) for weight change, or mpy (milligrams per year) for thickness changes.
Ability of a material to withstand corrosion in a given corrosion system.
PipeA long tube of clay, concrete, steel, metal, wood, etc., for conveying water, gas, oil or other materials. with ridges (corrugations) going around it to make it stiffer and stronger. The corrugations are usually in the form of a sine wave a+B181nd are usually made of galvanized steel or aluminum.
The lid at the top of the manhole which can be removed when access to the interior of the manhole is required.
Fracture lines visible around the circumference and/or along the length of a sewer.