Ключевые слова: background, chemical, connection, construction, control, energy, engineering, equipment, fuel, fuel and power generation, gas, gasoline, heavy, industrial, industry, iron, iron metal, metal, nuts and bolts, old, outdoors, pipe, pipe tube, pipeline, piping, pollution, power, pressure, production, pump, stainless, steel, supply, system, technology, tube, valve, wall, white, yellow,