Onshore Wellhead Severance using Portable Ultra High Pressure (UHP) Water Jet Cutting Tool
Overview
Several plugged and decommissioned wellheads were required to be removed on shore at Barrow Island, off the coast of Western Australia.
A cold-cutting technique was required to sever the wellheads as there was a risk of explosive gas being trapped in the annuli of the wellhead liners. As a leading innovator in high and ultra-high pressure water jet cutting, iasgroup was approached to develop a system capable of cutting the wellheads safely and efficiently.
Scope
The wellhead elements had the following specifications:
| Structure | Gas wellheads |
| Application Type | Severance, lifting and transport of wellheads |
| Operating Environment | Remote, environmentally sensitive |
| Quantity | Multiple wellheads |
| Cross Section | Steel circular hollow section containing 3 steel liners |
| Cut Dimensions | Typically diameter 245mm |
| Method | Portable Ultra High Pressure Water Jet Cutting Tool |
Solution
- In-house design developed specialised portable cutting tooling and abrasive delivery systems
- Truck mounted Ultra-high pressures water cutting system using 40,000psi abrasive injection jet (AIJ) technology, capable of cutting through multi-liner wellheads
- State-of-the-art quality control, testing and monitoring systems
- Compliance with strict environmental regulations
- QA and inspection and test plan record provided to Client
Benefits
- Cold cutting technique removes risk of explosion due to residual gases in the wellhead
- Improvement in quality and efficiency through state-of-the-art automated precision cutting and monitoring systems
- Accurate scheduling of works as cutting system was truck mounted and portable, significantly reducing mobilisation and setup times
- Removal of wellheads safely, on time (14 days in total) and on budget
- Reduction in disturbance to habitat through non-explosive method of wellhead removal
