Having completed the design of Oil Metering and Prover skids for Yamal LNG Oil Metering System, Russia, as a subcontractor to Emerson Asia Pacific, Nautec received the order from Hai Leck Engineering, a contractor of Emerson, for the design of a portable cabin to facilitate water draw calibration of the prover with minimum ambient of -36 deg C and Zone 2 hazardous area.
- Structural design of the cabin
- Mechanical design of the water tank
- Piping design of water piping within the cabin
- Electrical design of the power supply to water heater, pump, space heaters and lighting design
- Instrumentation design of the water temperature control
- The challenge was to design the portable cabin with an inside temperature maintained at 10° C where minimum outside ambient temperature was –36° C and also to verify that the temperature drop across the prover during water draw is within +/- 0.2° C with the ambient of -36° C.
- The structural design of the cabin was complex due to its portability and extreme temperature variation and involved several analysis. The design was unique and had to be developed from scratch because there is no parallel.
- The cabin was located in a Zone 2 area and all E&I equipment had to be explosion proof
- The cabin design was a multidiscipline effort involving Structural, Mechanical, Piping and PDMS, Electrical and Instrumentation engineering services.
- Nautec’s Process group verified the temperature drop with Hysis simulation.
- The cabin had a water tank with heaters and temperature control to maintain the water temperature at a predetermined value. The calibrated seraphin cans were mounted on top of the tank to allow gravity flow. There was a pump to circulate the water through the prover and return to the tank through the seraphin cans.
- A PDMS model was developed by the Piping group and general arrangement and piping isometrics were derived out of the model.