BJ Services Co. used its InjectSafe WR (wireline retrievable) surface controlled subsurface safety valve (SCSSV) with its BJ Dyna-Coil capillary string inside existing tubing to bring
a lifeless Gulf of Mexico well back on line with daily production of 1.2 MMcf of gas.

Liquid loading shut off production from the well with a tubing-retrievable SCSSV, but well economics couldn’t support intervention to pull the existing tubing and SCSSV and run a smaller-diameter completion.

Before the operator plugged the well, however, it decided to try the BJ system, which

BJ’s InjectSafe SCSSV with integrated Dyna-Coil capillary string returned a dead well to profitable operation. (Image courtesy of BJ Services Co.)
requires modifying the wellhead and locking out the existing tubing-retrievable safety valve.
The use of capillary strings allows direct, continuous downhole treatment to apply cures for liquid loading, wax, asphaltene, scale, salt or corrosion in the well bore. After researching an individual well’s situation with well samples, field surveys, laboratory tests, production analysis and computer simulation, it typically suggests a capillary string installation with 1/4-in. or 3/8-in. tubing.

With those elements installed and tested, the company can hook up the chemical injection equipment. That system normally includes an injection pump; a chemical pump; a regulator or control valve and tanks; the production chemicals; and a manifold assembly with a check valve, filter and pressure gauge.

If a well has an SCSSV in place, it can be treated with BJ’s InjectSafe SCSSV, a proprietary safety valve that supports approved chemical placement at or near the perforation below the safety valve without impairing the operation of the safety valve.