Ключевые слова: abstract, background, building, canalization, circular, closeup, conduit, construction, corroded, corrosion, cut, cylinder, diameter, drainage, duct, edge, heap, industrial, industry, iron, large, line, manufacturing, many, metal, opening, orifice, pipe, pipeline, pipework, piping, red, reddish, round, rust, rusty, sewage, sewer, site, soilpipe, stack, steel, store, surface, texture, tube, tubing, warehouse, water,