Fixed Lines to Surface
The simplest grouting approach, and the one most commonly used in shallow waters, uses fixed lines to the surface for both packer inflation and grout injection. The lines are installed in the fabrication yard and are a permanent part of the structure. Grout lines are carbon-steel pipe; packer inflation lines, if required, are stainless-steel tubing.

Grout Packer Inflation
Primary grout packer inflation is via fixed surface lines, usually stainless-steel tubing. Compressed air or nitrogen from the surface provide pressure to inflate grout packers. In some cases, passive seals are used instead of packers.

Contingency Systems
At depths up to 500 feet (152 m), contingency grout-injection and packer-inflation can be via redundant fixed lines or ROV hot-stab connections. Diver-installed, quick-disconnect lines can be used at depths less than 200 ft (61 m). At depths below 600 feet (183 m), contingency grouting and packer inflation lines are usually ROV-installed.

Conventional Surface Lines
In the conventional fixed surface-lines arrangement, there are normally primary and contingency grout lines and primary and secondary grout packer inflation lines. Conventional systems can be used for both single-stage and two-stage grout jobs.

Selective Sliding-Sleeve Grout Valve
Single or dual sliding-sleeve grout valves provide a means for pumping grout to multiple locations through one fixed line from the surface. They can be used for multi-stage grouting of a single sleeve or single-stage grouting of two or three pile sleeves. Stainless-steel balls and sliding sleeves are used to divert grout to different annuli. After initial grouting is completed, a ball is dropped from the surface. The ball seats on the internal valve sleeve, and pressure is raised to 450 psi to slide the sleeve downward, opening a subsequent grout path. For a dual valve, a second, larger ball is dropped to actuate a second sliding sleeve.

The typical conventional grout package for shallow-water structures uses fixed primary and secondary lines from the surface. Group packer inflation lines are not shown.
 

Sliding sleeve valves are used to provide secondary grout lines without adding fixed lines from the surface. Grout packer inflation lines are not shown.