... widely used in many industries such as petroleum, oil refining, food, dairy, paper making, chemicals, ... , saline, phosphate, calcium compound, etc.·Oil refiningLubricating oil, aromatics, fuel oil, and vegetable oil, etc.·Food processingTomato juice, grape juice, ... , etc.·Petrochemical Natural gas, coal gas, lubricating oil, and oil / water interface Technical parameter·Signal outputTwo wire current ...