Pneumatic tubes are used to connect pneumatic control mechanisms to transfer compressed air to actuators, tools, valves etc. There are many fittings available to connect these tubes to components. Pneumatic tubes comprises mainly of 3 types though there are different types available: polyurethane, nylon, polyethylene tubes each of which are used for particular applications.
Polyurethane tubes are flexible, durable and abrasion resistant tubes used mainly in vacuum, medical, laboratory applications etc. It is also able to withstand applications with contact to fuel and oil.
Nylon tubes are strong, flexible and lightweight tubes designed to be used for high pressure pneumatic applications with high resistance to flexibility fatigue.
Polyethylene tubes are chemical & solvent resistant and flexible tubes applied in low pressure pneumatic applications. They are also relatively cheaper.