Built near the company’s headquarters in Colico, Italy, the steel chamber structure is 2.5 m in diameter and 7.5 m high and weighs 190 tons. It is able to support an internal pressure of 27,000 tons, as is found in the depth of the sea where, at 4,500 m under the marine surface, the pressure comes to 450 atm.
To test ATV’s products, the hyperbaric chamber is filled with water, the lid is tightly closed, and then pumps add more water to increase the pressure. As the liquid is compressed, the chamber sides react elastically to the internal forces, which can reach more the 560 bar.
On the chamber itself, motors are used for water valve opening and closing because they have to operate under the water without crashing or stopping. Many sensors are positioned inside the chamber to continuously monitor pressure values. Other devices monitor the water temperature, which must be kept at 4 °C as it is in the ocean depths.
Field values are detected and sent through a CANbus network to a Modicon M340 PLC from Schneider Electric for control tasks. Field data is also sent in parallel to a PC that contains a database and can also control chamber operations in case of a PLC fault. If pre-determined security values are reached, the pressure pumps are immediately stopped by the system, and emergency valves come into action if an electronic problem occurs.
Ilaria De Poli, [email protected], is an editor at “Fiera Milano Editore,” a magazine covering automation and manufacturing in Italy.