Learnings

Outcomes

The outcomes of the project include a fully operational, fit-for-purpose prototype Nitrogen purging trailer designed, fabricated, and tested.

The trailer integrates: Two banks of three X475 200-bar Nitrogen cylinders (50Ltrs), Auto changeover first stage regulator, High pressure manifold unit, Outlet pipework to hose reel set 80mbar, Hose Reel with 20mtr ¾” hose, Fire Extinguisher box and Wheel Chocks. The unit is mounted on a repurposed Indespension Flatbed Trailer (FTL35166), with a payload of 2,709 kg, and suitable for deployment in constrained road access environments. The purge trailer P & ID, operation manual and component specification documents have been produced to aid in training and trailer usage.

Lessons Learnt

The key lesson learned was that initial design assumptions about regulator pressure ratings and flow rates needed adjustment to meet actual field conditions, particularly for larger diameter pipe sections. The replacement of the low-pressure regulator with a medium-pressure one significantly improved system performance, enabling nitrogen injection rates to reach 100 m³/hr as required for effective purging.

This underscores the importance of early, detailed analysis of flow requirements based on network geometry and emergency scenarios to inform system design. Future projects should integrate this analysis earlier in the design phase.

To move from TRL 8 to TRL 9, it is recommended that the purging trailer be subjected to:

a) Live field trials under emergency simulation conditions, including variations in pipe diameter and terrain.

b) Operator training exercises using the developed work instructions to validate usability and safety.

c) Seasonal and environmental stress tests, particularly in constrained-access network areas, to assess trailer deployment logistics.

A formal post-trial validation study should also be conducted to assess effectiveness, operability, and any further refinements needed