Project Overview:
Location: HF Tank Farm
Duration: 7 months
Value: (Piping Scope): £1.7 million GBP
Completion Date: May 2025
Hydrofluoric acid is a highly corrosive and toxic chemical widely used in the petroleum and chemical industries, particularly in alkylation units.
Due to its hazardous nature, the handling, storage, and transfer systems for HF require precision engineering, high-integrity piping systems, and strict safety protocols.
This case study outlines the construction of piping systems for a new HF tank farm, focusing on challenges, solutions, and key performance outcomes.
Project Scope
The piping installation scope included:
- Fabrication and erection of over 2,000 meters of piping
- Integration with vertical storage tanks
- Tie-ins to HF unloading bays, pumps, and dosing systems
- Installation of double-containment piping & HF(N) compliant LTCS for critical runs
- Compliance with ASME B31.3 & DVS 2210
- Hydrotesting, pneumatic testing, radiography and system flushing
Due to HF’s corrosive nature, the following materials were selected:
- Piping Material: Polypropylene PP-H PN10, 316L Stainless Steel, PVDF, API 5L Galvanised, A106 & A333 (HF/N)
- Gaskets: Gore 800 UPG
- Flanges/Fittings: ANSI-rated
- Valves: Plug valves and ball valves with full HF compatibility
Material procurement required long lead times due to specialized alloys and international sourcing from qualified vendors.
- Design Codes: ASME B31.3, DVS 2210
- Layout Considerations: Shortest routing with minimized flanges and welds to reduce leak potential
Execution Strategy:
- Pre-fabrication of spools in a controlled workshop environment
- Installation sequence coordinated to avoid contamination and ensure safety
Welding and QA/QC:
- GTAW (TIG) used for all metallic welds
- HF compliant A333 pipe and fittings with supplementary requirements100% radiographic testing on critical welds
- 69 separate test packs
- 2355 welds completed across all systems
| Challenge | Solution |
|---|---|
| Long material lead times | Early procurement planning and dual-sourcing strategy |
| Material constraints | The specification required the use of PP-H dual contained & HF(N) compliant pipework in corrosive areas. Long lead times and supply chain disruptions required early procurement and close coordination with suppliers |
| Concurrent worksite activity | Co-ordination with civil, electrical and structural contractors was critical to prevent schedule clashes |
- TRIR (Total Recordable Incident Rate): 0.0
- Near Misses: 3 (Investigated and resolved with corrective actions)
- Man Hours: Over 16,000 site hours incident free
The piping system underwent:
- Final hydrotesting and pneumatic testing on 69 separate test packs
All deliverables were completed and signed off by the client’s QA/QC and safety teams.
As-built drawings and data books were submitted as part of the Mechanical Completion Package (MCP).
Key Outcomes:
- Zero leak incidents during startup
- Project completed on schedule
Lessons Learned:
- Early engagement with specialized material suppliers is critical
This project demonstrated that with appropriate planning, skilled personnel, and strict adherence to safety and quality standards, complex HF piping systems can be delivered efficiently and safely. The successful execution of the HF Tank Farm piping installation positioned the facility for safe, long-term operations and met all regulatory and client requirements.