Having completed successful ballast water retrofitting of one of its LNG Carriers, Goltens was once again contracted by one of the world’s largest LNG owners and operators to complete similar turnkey retrofits on two 15-year old, 83,000 DWT LNG carriers.
Retrofit on large vessels
While Goltens is a globally renowned company in ballast water retrofits, having completed well over 850 retrofit projects, however, designing and executing the retrofit on such large vessels, with one of the world’s largest ballast water treatment systems, presented a unique set of challenges.
The scope was comprehensive and included completion of the following steps throughout the project lifecycle:
- 3D scanning & vessel survey
- Basic and detailed engineering
- Class approvals & Shipyard Management
- Procurement & Prefabrication
- Supply of material (big bore piping, small bore piping, site run piping & fittings, valves, actuators, cable & etc.)
- Installation and supervision in the yard
Design & Engineering planning
For each vessel, Goltens deployed a skilled team to perform 3D scanning and perform ship checks. The scans were then registered and Goltens began the baseline design with 3D modelling software. Once the baseline models were accepted, Goltens moved quickly to complete the full engineering design package for approval by the owners and class prior to procurement of materials & equipment for prefabrication.
As was the case with the prior installation, the primary challenge for Goltens was space. The sheer size and number of the Techcross ballast pumps coupled with the limited area surrounding them was a design and planning challenge.
Space management optimisation
Quality management was also a primary focus during the prefabrication phase
The design team developed plans that optimised the space management and reviewed the designs thoroughly, in order to ensure the machinery could be successfully installed and operated.
Quality management was also a primary focus during the prefabrication phase. Numerous quality and integrity inspections were completed by Goltens Engineers to ensure that the prefabricated pipe spools were satisfactory. As a final step, non-destructive testing was carried out by Goltens and witnessed by the owner’s representatives.
Installation phase
The installation and commissioning of the systems were both completed at MMHE Shipyard in Johor, Malaysia. Goltens deployed a skilled workforce of 60 personnel, including supervisors, in order to ensure that the installation was executed to the design and completed successfully, despite short docking schedules.
Installation followed the same 5 stages, which were established in the prior successful Techcross retrofit.
The 5 stages of installation include:
- Stage 1: Remove the existing pipes to install the tie in spools, lift out the existing pipes and install the newly fabricated big bore (600A) pipes.
- Stage 2: Fabricate & install the foundation supports for the equipment (Electro Chamber Unit, Power Distribution Equipment, Auto Neutralisation Unit & TRO Sensor Unit)
- Stage 3: Lifting the equipment safely into the lowest deck of the Engine Room and securing the equipment.
- Stage 4: Completion of electrical works including: cable pulling, cable termination at main switchboards, power distribution equipment and equipment onsite.
- Stage 5: Installation of the small-bore piping between the equipment and big-bore spools.
Goltens worked closely with the owners and the shipyard throughout the process to drive progress and avoid any delays in completion. As a result, both installations were completed within the allotted time with one being executed in 18 days and the other in 20 days.