Diamond Wire Saw Subsea Pipeline Cutting Case Study: PCSB SKO Pipeline Replacement Project (Sarawak, 2019)

In 2019, PETRONAS Carigali Sdn Bhd (PCSB) Sarawak Operation (SKO) initiated a major pipeline replacement project to safeguard significant oil and gas production in the Bokor and Temana fields, offshore Sarawak, Malaysia.

1.The Challenge: Aging Pipelines and Complex Subsea Conditions

The SKO pipeline network operates a total of 172 pipelines with an estimated total length of 1,477 km. Most are offshore pipelines facing significant integrity challenges:

Microbial Influenced Corrosion (MIC) - Internal corrosion arising predominantly from microbial activity

Aging pipeline assets- Many pipelines exceed 25 years of service

Complex multi-layer structures- Subsea pipelines typically consist of concrete weight coating, anti-corrosion coating, thermal insulation, and steel pipe body

Conventional cutting methods-hydraulic shearing, explosive cutting, and thermal cutting-struggle with these complex layered materials and pose significant safety and environmental risks.

2.The Solution: Diamond Wire Saw (DWS) with Continuous Closed-Loop & Anti-Jamming Technology

The PCSB SKO pipeline replacement project deployed Diamond Wire Saw (DWS) technology-the industry-standard solution for subsea offshore pipe cutting.

 Continuous Closed-Loop Design 

The DWS uses a continuous-loop diamond cutting wire that enables fast, clean cutting across pipes of varying materials and thicknesses. Unlike reciprocating saws that require frequent directional changes, the continuous-loop design maintains steady, uninterrupted cutting motion-dramatically improving cutting efficiency and surface quality.

Anti-Jamming Technology

Even if structural displacement occurs during the cutting process, the saw will not jam or stall. This anti-jamming capability is critical in subsea environments where pipeline settlement, tidal currents, and thermal expansion can cause unexpected structural movement.

The anti-jamming feature directly reduces the risk and cost of equipment seizure in offshore operations.

3.Key Technical Advantages of DWS in Subsea Pipeline Cutting

Handling Complex Multi-Layer Pipeline Structures

Subsea pipelines are composed of multiple layers-concrete weight coating, anti-corrosion coating, thermal insulation, and steel pipe body-making them difficult for conventional methods. Diamond wire saw cutting is specifically designed to precisely and reliably cut through such complex layered materials.

 Clean Cuts Without Blade Jamming

The continuous closed-loop design ensures fast, clean cutting even under structural displacement. The precision of diamond beads produces a smooth cut surface, drastically reducing the time needed to prepare pipe ends for replacement tie-ins.

Minimal Environmental Disturbance 

Compared to hydraulic shearing and explosive cutting, diamond wire sawing generates significantly lower vibration and noise, reducing disturbance to marine life. The cutting process produces less heat, preventing thermal damage to surrounding components.

 Supports Diverless & ROV Operations 

Modern DWS systems support ROV or hydraulically actuated diverless deployment, capable of cutting pipes with outer diameters ranging from 4 inches to over 50 inches. The adaptive feed system automatically adjusts cutting speed based on pipe material and thickness.

The 2019 PCSB SKO pipeline replacement project in Sarawak, Malaysia, stands as a compelling example of how Diamond Wire Saw (DWS) technology with continuous closed-loop and anti-jamming features delivers superior results in subsea pipeline cutting.

By combining continuous closed-loop design, anti-jamming capability, ROV compatibility, and minimal environmental impact, DWS technology has become the industry-standard solution for subsea offshore pipeline cutting-enabling safer, faster, and more cost-effective pipeline replacement operations worldwide.