Mooring Chain Severance
Precision Mooring Chain Severance
Decom Engineering are the industry's leading specialists in subsea mooring chain severance. Our patented Chopsaw technology delivers precision cold-cuts up to 3× faster than standard diamond wire methods — trusted by TechnipFMC, Subsea 7, Petrobras, and Woodside across 150+ completed projects worldwide.
Contact UsThe Global Standard
The Global Standard in Mooring Chain Severance
In the high-stakes world of offshore energy, mooring chain severance isn't just about making a cut — it's about protecting your schedule and your assets. While Decom Engineering is a recognised leader in decommissioning, our specialised subsea Chopsaws are becoming the standard for offshore installation and construction campaigns worldwide.
When high-tension mooring lines need to be severed, we deliver the speed, safety, and engineering expertise to keep your campaign on schedule and under budget. Standard cutting tools often struggle with shifting loads. Our Chopsaws are specifically engineered to sever mooring chains while they remain under large amounts of tension — a critical capability where chain stability is not guaranteed.
3×
Faster than diamond wire
150+
Projects completed
Market-leading speed
Time is the most expensive commodity offshore. Our Chopsaw technology delivers precision cold-cuts that no other method can match.
Market-leading speed
Industry-Leading Cut Times
Time is the most expensive commodity offshore. Our Chopsaw technology delivers precision cold-cuts that no other method can match.
76mm Mooring Chain
8
Minutes
Average cut time
120mm Mooring Chain
18
Minutes
Average cut time
137mm Studless Mooring Chain
15
Minutes
Average cut time
182mm Studless Mooring Chain
30
Minutes
Average cut time
The equipment
The Tools for the Job
Our C-Series Chopsaw range is meticulously engineered to meet the demands of mooring chain severance across all environments and chain sizes. The C1-16UL — the first of its kind — is designed for ultimate portability and efficiency, perfect for cutting chains and risers under tension.
Innovation
Innovation That Eliminates Risk
We take on the safety challenges that other industry suppliers decline. Every solution we engineer puts your crew further from harm and your project closer to completion.
Zero-Drop Safety
When a major client faced the critical risk of dropped objects during severance, we designed and engineered a bespoke faux link clamp system from scratch. These custom retention clamps securely hold severed half-links in place — a solution other suppliers could not provide.
Crane-Free Deployment
Custom ROV skids allow tools to be deployed without a crane, increasing operational flexibility and saving critical vessel time on every campaign.
Exceptional Blade Life
100% success rate to date. Multiple cuts per blade with 5-minute blade changes — minimising costly offshore downtime and keeping your campaign on schedule.
Global reliability
Global Reliability You Can Trust
With over 150 projects completed, we have the global footprint and technical authority to support your next campaign — including Jones Act compliant operations in US waters.
Maximise your vessel time and cut your project costs. Whether it's a rapid decommissioning campaign or a complex new installation, Decom Engineering delivers.
150+
Projects completed
Yes
Jones Act compliant
100%
Blade success rate
Trusted by industry leaders
Track record
Proven in the Field
From Gulf of Mexico deepwater installations to Australian FPSO campaigns, our Chopsaw technology has delivered on the world's most demanding mooring chain severance projects.
Case StudyShenandoah Mooring Chain
Subsea 7 faced a dual challenge: rapid cutting of 12 sections of large 137mm studless mooring chain, and a solution to securely retain all severed links to ensure zero dropped objects — a requirement other suppliers declined. Decom Engineering engineered a bespoke "faux link" clamp system, optimised the C1-16UL Chopsaw with integrated buoyancy for ROV operation, and trained US personnel for Jones Act compliance. All 12 cuts were completed successfully with the fastest cut taking only 15 minutes and zero dropped objects recovered.
View case study
Case StudyFPSO Mooring Severance
A long-term rental project with CBO Group, operating for Petrobras in Brazil. The scope required cutting large-diameter mooring chain reliably under significant tension. By developing a custom ROV skid, the solution eliminated the need for crane deployment. The equipment consistently delivered clean cuts in under 30 minutes, with an impressive average of just 18 minutes.
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Case StudyStybarrow Mooring Chain
Decom Engineering was contracted by TechnipFMC to support Woodside's decommissioning campaign at the Stybarrow field. The C1-24 Chopsaw was crane deployed and powered subsea via ROV, with hotstabs supplied by Decom. The saw delivered industry-leading cut times of just 8 minutes per mooring chain link, completing all 24 cuts with consistent performance and minimal blade changes.
View case studyScarborough
C1-10
Project recently completed. Case study coming soon.
Case study coming soon
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Providing solutions through innovation, reliability, and unparalleled customer service. Contact our team to learn more about mooring chain severance and our full range of subsea cutting solutions.