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  • Side-entry system allows capillary string intervention, remedial work

    J.W. Noles

    Over the past several years, use of capillary tubing as a means for chemical injection has become increasingly common. Capillary tubing can provide a cost-effective way of introducing soap, corrosion inhibitors or other chemicals within or below the production tubing. These small strings have proven effective as treatment conduits for a wide variety of reasons without damaging or interfering with the production string. One common use of capillary tubing has been for soap injection. The small stainless-steel line is installed down to the lower section of the wellbore to a depth where liquid accumulation is suspected. Soap is then injected, either intermittently or continuously, down the line and mixed with the wellbore liquid. The migrating gas agitates the liquid / soap mixture and forms foam. The viscosity of the foam helps to resist gas-liquid separation, allowing the liquid to be recovered at velocities below what is considered a "critical" velocity.

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2013 Fracturing Technology

2013 Fracturing Technology