Background
UK start-up company (spun out from Qinetiq) developed a unique product to remotely monitor the wall thickness of pipelines used in the petrochemical and oil and gas industries. Using discrete RF modules directly connected to specific points on an installation, continuous measurement and monitoring of the wall thickness is remotely managed. Traditionally this activity is carried out manually with inspection staff having to access the relevant areas over a complete site, so not only is costly but also very time consuming.
Brief
Equipment was to be installed outside in a wide range of environments (from desert to near arctic) so it needed to be waterproof and should be capable of withstanding sand and dust. A range of waterproof TNC/MCX bulkhead mount adaptors, waterproof TNC plug connectors, waterproof quadraxial (4-way for signal and datalines) connectors were required all of which were required to be ATEX approved in the equipment by the customer. There were also some internal cable assemblies requiring ATEX approval –(careful selection of heat shrink sleevings).
Challenges
- The outdoor operating environment, 200 degree C operating temperature ultrasonic thermocouple temperature.
- Waterproof to IP68, impervious to sand and dust, capable of meeting Atex approval (material selection, cable assemblies)
- A custom connector 4 way Quadraxial design that was aesthetically similar to the TNC adaptor design, the ability to ensure the correct device was fitted to the correct TNC bulkhead adaptor.
Solutions
This project developed on from existing TNC/MCX adaptors, plus a new design quadrax (4 way) connector. Standard and reverse polarity designs ensured that incorrect device connection could be eliminated, and the materials data and samples were submitted to undergo ATEX approval testing. The adaptors were waterproof both at the bulkhead and sealed internally to prevent moisture ingress through the internal connector components.
A mating TNC plug connector, sealed to IP68 rating was developed, assembled with a 200 degree Celsius rated cable (approved by the customer) was proposed to meet the specific requirements. A custom designed 4 way mated pair of connectors were designed, developed and prototyped to be submitted for customer approval and qualification. The design in Atex approved materials required a specially designed alignment feature to ensure successful mating of the 4 contacts whilst still providing an IP68 sealed connector.
Summary
Product qualification finalised and certified, the product entered the market place after a relatively long development time mainly due to the launch of the new company. The TNC/MCX adaptors (standard and reverse polarity) are now firmly established as a standard production Pisces adaptor, and have been in production for over 12 years. Similarly, the mating half TNC plug connector is now in full production and is a standard item in Pisces waterproof connector range.
The 4 way connectors housed in an identical TNC adaptor body, are currently in production and available for other applications. The same IP68 rating applies meaning the connectors are sealed in their unmated condition as well as to the bulkhead panel.