Sofis recently supplied FlexiDrive remote valve operators to the INS Vikrant, an aircraft carrier in service with the Indian Navy. The remote valve operators are part of the ship’s HVAC system. This system was supplied and installed by Johnson Controls, one of the world’s biggest suppliers of HVAC/R (heating, ventilation, air conditioning, and refrigeration) solutions for marine and naval applications.
HVAC systems regulate and move heated and cooled air throughout the ship, where ducts carry the air. As ducts are connected throughout the ship, water can easily find its way from one section to the other, and to the rest of the ship. Therefore, to maintain the watertight integrity of the ship sections, shut-off valves are to be installed on ducts. Initially, design engineers at Johnson Controls considered installing valves on each side of watertight sections, allowing safe operation from the side that is not flooded. However, this potential solution would increase costs and add considerable weight to the ship so other options were evaluated. One such option was to operate one single valve from either side of the bulkhead, using a physical connection of rods and bevel gears. Again, operating and maintaining these kinds of systems is costly in addition to the need to replace rods and bevels after five to ten years due to wear and tear.
The design team of Johnson Controls realized that in case of severe flooding, shut-off valves on ducts should ideally be operated remotely. To prevent safety breaches, it was therefore decided that duct valves were to be equipped with remote valve operators. This way, valves can be operated from a safe distance in case of flooding. Johnson Controls was looking for flexibility in terms of component breakdown, and this led them to the Sofis FlexiDrive. Instead of rods, FlexiDrive uses a flexible cable, that can be bent to any desirable position.