SV Design - Mechanical Design Features
Great attention to detail has been paid to the mechanical design of Valeport Sound Velocity Sensor, ensuring as much structural rigidity as possible. This is partly to maintain our reputation for manufacturing rugged instruments that can be used with impunity in the harshest environments, but primarily because maintenance of the precise geometry of the sensor is critical to providing accurate sound velocity readings.
Firstly, as with all our products, all exposed metallic components are manufactured from titanium. Not only does this offer exceptional mechanical strength for use up to full ocean depth, but it also resists corrosion to ensure that the sensor will last for many years.
The most important aspect of the sensor design is the use of a specially manufactured carbon composite material to hold the acoustic mirror. These legs basically define the distance over which the sound pulse will travel, and it is therefore absolutely critical that they remain stable under all conditions. For that reason, we had this particular composite researched and developed to our specifications, chief amongst which was that it must have a thermal expansion coefficient (TC) as close to zero as possible. That is to say, unlike most other materials, it neither expands nor contracts when subjected to changes in temperature.
Although it is known that many composite materials have a low TC (some even have a negative TC, so they contract when heated), we felt that in order to substantiate our claim to be the best in the world, we had to be certain that our composite was tested and proven to match our TC requirements. Tests at the National Physical Laboratory in the UK are therefore performed on each batch of carbon composite material that we procure, to ensure that we can continue to claim these levels of performance.