Ключевые слова: abstract, background, barrel, black, blue, business, cad, concrete, design, designer, energy, engineer, engineering, equipment, estate, factory, fuel, gas, heavy, illustration, industrial, industrial plant, industry, insulation, line, machine, manufacturing, metal, oil industry, pairs, pipe, pipeline, piping, plant, power, pressure, production, pump, shine, sign, sketch, stainless, steel, supply, technology, tube, valve, worker, workshop,