A Downhole sensor is a device which can measure various properties such as pressure, fluid flow rate from each branch of a multilateral well, vibrations, fluid flow regime, fluid holdup and composition.

These devices can be permanent and left in one place for months, even for years.

There are types of downhole sensors are specifically designed for applications at high pressure and high temperature up to 450°F, where a long-lasting stability plays a major role. They are specially important in corrosive environments.

One type of downhole sensor series is designed to eliminate acceleration sensitivity, requiring no virtual calibration. While choosing a downhole sensor for any application, you should consider those which are fully calibrated and environmentally tested.

It’s also very important that the material used in a downhole sensor is compatible with corrosive metals, like H2S and others. It can be, for instance, a high-resistance platinum RTD for greater sensitivity or for long-term stability and accuracy.

Reliable sensors are essential especially for sub-sea machines enhancing oil extraction, because they minimize the use of chemical injection. One more important feature those sensors should have is that they must be easy to clean, without the need to be brought back on the surface (it requires time and money) or must have significant power, for instance with a thick cable. By combining a highly resistant membrane and in-situ cleaning capacities, those problems will be solved.