Ключевые слова: boiler, cave, channel, check, chemical, circular, confined, construction, corrosion crude, danger, dark, dirty, economy, energy, engineering, environment, equipment, flange, flow, fuel, gas, gate, heat, hole, industrial, line, machine, metal, mine, mud, oil, open, petrol, pipes, power, pressure, pump, repair, rusty, safety, sand, steel, storage, storage tank, technology, texture, tool, tunnel, work,