Why this product was developed
In this application, the customer needed a way to monitor the condition of a subsea pump stator during operation. The main concern was overheating, particularly in the stator rubber element, which could indicate that the pump was running outside its intended operating condition.
Under normal operation, temperatures were typically around 10 to 20°C. If temperatures began to rise significantly, reaching 60°C or even 100°C, this provided an early warning that the pump required investigation.
For subsea systems, where intervention is difficult and costly, that kind of early insight is highly valuable.
The customer challenge
This project required more than a standard temperature sensor. The solution had to:
integrate directly into the pump housing
operate reliably in a harsh subsea environment
withstand seawater exposure and pressure loading
remain protected from direct contact with the pumped fluid
avoid exposure to internal system pressure
deliver a stable and dependable monitoring signal on an ROV-mounted system
The deployed system operated at depths of around 300 to 400 metres, while the sensing solution was developed for deepwater applications requiring operation to 3000 metres, depending on configuration.
The custom SSTT solution
To meet these requirements, we developed a custom subsea temperature transmitter based on our SSTT platform.
The sensor was mounted directly into the pump housing so it could monitor the thermal condition of the stator without being exposed to the process media itself. This gave the customer the temperature feedback they needed while protecting the sensing element from the more aggressive aspects of the application.
The result was a compact, robust and application-specific solution that supports reliable subsea operation and gives operators earlier visibility of developing faults.
Key benefits
Early warning of stator overheating
Helps protect critical pump components from thermal damage
Designed for harsh subsea environments
Installed through the housing, not directly into the process
Supports condition monitoring and fault investigation
Can be tailored for specific mechanical and electrical requirements
Suitable for use on subsea and ROV-deployed systems
Typical applications
While this version was developed for subsea pump stator monitoring, the Custom SSTT is suitable for many other underwater and offshore applications, including:
subsea pumps
stator and housing temperature monitoring
ROV-mounted systems
subsea pods and enclosures
oil and gas equipment monitoring
pipe and seal temperature monitoring
other customer-specific subsea instrumentation projects
Example specification
A typical SSTT subsea temperature sensor configuration includes:
Sensor technology: Resistance thermometer
Output: PT100, 3-wire
Accuracy: PT100 Class A
Temperature range: 0 to +50°C
Ambient temperature: -20°C to +65°C
Media wetted parts: UNS31803 Duplex Stainless Steel
Electrical connection: 3-pin subsea wet-mateable connector
Process connection: M10 x 1.5 external thread
Environmental protection: IP68, permanent submersion to 2000 m depth
Custom versions can be adapted to suit different output, temperature, depth and connection requirements.
