Ключевые слова: abstract, background, black, build, business, canalization, cesspit, circle, circular, construction, culvert, cylinder, development, ditch, drain, drainage, ducts, engineering, hardware, improvement, industrial, industry, manufacturing, many, materials, new, pipe, pipeline, pipes, pipework, plastic, plumbing, polyurethane, polyvinyl, pvc pipe, round, sanitary, sewage, sewer, sewerage, stack, stacked, tube, tubes, tubular, vinyl, warehouse, water,