Project Background:
PDO intends to develop the Active fire protection system and awarded the “KGP & SNGP Fire Water System Project” EPC Contract to M/s Worley Parsons-Arabian Industries (JV) Oman. The 3D Modelling and Pipe Stress analysis for downstream of Deluge Skids scope was awarded to M/s Tyco Limited Co LLC, Oman as Sub-Contract for EPC. Design, Engineering and 3D Modelling of Deluge Skids and Deluge valve downstream the Fire water Piping Network was performed by Elixir engineering for Tyco Limited Co LLC, Oman.
About Facilities:
Two new Firewater Storage Tanks (T-86001/2), each of capacity 4780 m3, have been installed to supply water for new firewater pumps. The capacity of each tank is equivalent to 6 hours of peak firewater demand of 795 m3/hr. Water for fire water storage tank filling is supplied by tankers. Water tanker is considered to have unloading pump. Both tanks are operated online and any one of the two tanks can be taken off-line for maintenance.
The Two Firewater pumps (P-8601/P-8602), one electric motor driven and the other diesel engine driven, each of capacity 795 m3/h, operates on 1 Working and 1 Standby philosophy. Electric motor driven pump works as the duty pump and diesel engine driven pump is on auto standby. Main fire water pump auto-starts when the ring main pressure drops to set point of 750 kPag and continues to run until stopped manually.
Two jockey pumps (P-8603A/B) (1 working and 1 manual stand-by) have been provided to maintain system pressure. The jockey pumps (each of capacity 15 m3/hr) maintain the ring main pressure between 800 to 850 kPa (g).
Two ring main headers supplies firewater to the entire facility. Firewater distribution system will consist of various hydrants, monitors etc. Ring header will also supply water for fixed foam system which will be installed at Condensate holding tank at KGP & SNGP.
Instrument air is required for control valves and this requirement has been met by the existing IA skids in both stations.
Biocide Chemical injection is required for firewater storage tanks to avoid bacterial growth inside tanks. The biocide injection is done batch wise, either by dumping of solid biocide tablets or by injecting hypochlorite solution using a temporary skid.
Execution Methodology:
- Review of P&ID for KGP and SNGP network.
- Review of Process design parameters and conditions
- Performing and Re-validating water demand calculation for each network
- Preparation of Piping and Valve Material Specification
- Performing Pipe wall thickness calculation
- Preparation of Line list
- Review of existing 3D model prepared by Client
- Creation of Admin modules in PDMS for Piping components and Skid arrangements
- Generation of preliminary pipe routing for both KGP and SNGP Network and ensure the coverage area of Sprinkler/ Fire Hydrant/ Foam arrangements
- Preparation of Support drawings and Support Schedule
- Identification of critical piping arrangements for Pipe Stress analysis
- Pipe modelling as per provided preliminary GA drawing in CAESAR II Software
- Definition of fluid and material properties as per project specification.
- Definition of environmental conditions as per project specification.
- Definition of External load conditions (Wind load, Wave parameters) as per project design specification. Earthquake or Seismic condition is not applicable for the design condition.
- Definition of Support type and support details
- Performing the Stress analysis for various load conditions (Thermal load case, Sustained load case, Hydro load case, Occasional load case and Transportation load case) as per project design specification and Stress analysis basis.
- Validation of pipe load values in all support locations and node points.
- Validation of deflection, displacement and Pipe stress values within allowable limit.
- Skid Nozzle loads are taken into the account while nozzle load allowable check.
- Finalizing the first anchor point outside of Skid and inside skid, based on the connecting nozzle loads.
- If stress and deflection limits are exceeded, the analysis will be re-performed for suitable Pipe Support and routing arrangements.
- If all stress and load values are within the limit, the Stress summary, Restraint summary with Input Echo are extracted and submitted to client.
- The necessary changes in GA drawing with respect to piping and Pipe support arrangements have updated in 3D modelling.
- Participation of 3D model review (30%, 60% and 90% model review) and preparation of 3D model review report.
- Ensure the Clash checking of piping network with other arrangements and constructability point.
- Piping loads and other components load values are provided to Structural team to check integrity of Structural arrangements.
- Definition of Piping loads (Axial, Vertical & Friction loads) in all support locations.
- Definition of other components load on the specified structural locations.
- Preparation of complete report with Results summary and Software results for Stress analysis.
- Final Submission of 3D model.
- Preparation and submission of GA drawings, Isometric drawings and Spool preparation, Primary support schedule and Secondary support schedule and Bulk MTO.
- Estimation of painting quantity.
- Providing support and addressing vendor queries during procurement.
- As-Built 3D model support based on the redline markups.
Deliverables:
- Pipe wall thickness calculation
- Pipe Material Specification
- Valve Material Specification
- Line List
- Primary Support Schedule
- Secondary Support Schedule
- Piping Stress Analysis Report
- Extracted GA drawing
- Extracted Piping isometric drawings
- Extracted Sprinkler coverage drawing
- Painting Specification
- Pipe Spool drawings
- Transportation philosophy
- Bulk MTO
