Structural Grouting Solutions
The Tamboritha/FoundOcean JV provides three main areas of structural grouting solutions to the offshore oil and gas and the renewables industries; Structural Pile Grouting Underbase Grouting and Ballasting, and Structural Repair and Strengthening. The combination of the experience of FoundOcean’s and Tamboritha’s personnel along with proven technologies enables us to deliver high-quality and cost-effective grouting services.
Structural Pile Grouting
FoundOcean has successfully grouted jacket and template structures in all energy producing areas of the world since 1974. Successful structural grouting relies on project preparation, experienced engineers and attention to detail during every stage of the project. FoundOcean understands that every platform is unique and so develops individual operating procedures for each project, giving details of the grouting operation and outlining contingency measures. On completion of a project, detailed reports are provided covering all offshore grouting operations and materials testing results.
The Tamboritha/FoundOcean JV offers as standard:
• Detailed quality assurance and control procedures
• Offshore materials testing laboratories and skilled technicians
• Skilled and experienced engineers, operatives and mechanics
• High capacity grout pumps to deliver grout to the structure
• A cement silo fleet with a capacity in excess of 2,000 tonnes
• Hose winches capable of deploying grout hose to the deepest structures
• ROV operated subsea grout connection systems
• ROV deployed grout density monitoring
Underbase Grouting and Ballasting
Our involvement in offshore operations extends past mixing and pumping grout. We take responsibility for the complete grouting operation including inflation of grout seals, cement transfer activities, supervision of grout hose deployment and participation in offshore planning meetings.
When a gravity-based structure is first set down, the irregular profile of the seabed results in uneven contact with the underside of the structure, with contact occurring only at the high points, and voids where the seabed is lower. This uneven support can lead to unacceptable structural loads. In order to provide a firm, even support to the underside of a gravity structure, a cement grout is pumped into the voids between the seabed and the structure.
The ideal cement grout for underbase grouting will simulate the seabed soil in strength, with a low compressive strength and even consistency. Our underbase grouts resemble a stiff clay when fully cured, with 28 day strengths as low as 1MPa.
FoundOcean has now carried out solid ballasting operations to offshore structures across most energy producing regions of the world. FoundOcean successfully completed a ballasting project for Veba Oil & Gas, pumping some 33,000 tonnes of ballast material into the Gravity Base Structure of the Hanze F2A facility in 2000. We have also ballasted spas and off-loading buoys.
Our ballasting capability is designed to fi ll the niche for projects where the quantity of ballast is uneconomical for dedicated ore transport ships. To meet this requirement for its offshore clients, FoundOcean has designed specialist compact and mobile ballasting systems which can achieve delivery rates from 200 to 1,000 tonnes per hour. These systems can be set up at the dockside or on a transport barge.
Structural Repair and Strengthening
Repairs and strengthening for offshore structures may be required for a number of reasons. The most common include fatigue, regulation amendments, collision damage and connecting additional Members.
FoundOcean provides three types of structural repair for offshore structures which solves each of these issues.
• Grouted Clamp: A clamp in which the outer sleeve is formed in segments which are placed around an existing joint. The splits are closed by pre-tightened bolts prior to the injection of grout into the annulus between the clamp and the existing tubular.
• Stressed Grouted Clamp: This is similar to a grouted clamp. Grout is placed into the annular space between the clamp and the existing tubular joint. The grout is allowed to reach a predefined strength prior to the application of an external stressing force.
• Grout filled tubular: A structural member which needs to be filled with grout for strengthening purposes.
FoundOcean can also provide advice and assistance with the analysis and design of structural repair solutions.
All our new offshore equipment is suitable for working in Hazardous Zone 2 areas.