Ключевые слова: bolt, connection, connector, construction, control, design, drain, element, energy, engineering, equipment, factory, fix, fuel, gas, gasoline, icon, illustration, industrial, industry, isolated, line, manometer, metal, object, oil, part, petroleum, pipe, pipeline, piping, plant, plumbing, power, pressure, production, pump, repair, sign, silhouette, steel, symbol, system, technical, technology, tube, valve, wate,