Nonexplosive Tubing Perforator Offers Controlled Cost-Effective Solution for Through-Tubing Gas Lift Installation
Authors: Babin Jacques , Mlcak Matthew , Oliveira Raquel Maia , Hernandez Angel 
Published: October 2015

Anoperatorin Baku, Azerbaijan was planning to create a gas lift configuration and needed to perforate 7-in., 32-lbf, 13% chrome, up to 0.51-in.wall thickness, heavy wall tubingwithout explosives. A nonexplosive mechanical tubing perforator conveyed on electric line avoided damaging the in-situ control lines and the casing. To meet the job parameters, a mechanical tubing perforator capable of generating up to 100,000 lbf necessary to perforate the 7-in. tubing was developed.

The 7-in. downhole electrical power generator actuated tubing perforator tool provided a controlled, nonexplosive, cost-effective solution to create a single perforation hole in tubing or casing without damaging in-situ control lines in the annulus. Tubing to annulus communication was established and through-tubing gas lift straddle was installed to allow increased production. When workover requirements necessitate rapid mobilization, the tubing perforator helps lower costs while providing a safe, effective, and dependable solution for perforating the tubing. Offering conveyance flexibility, the perforator can be run on slickline, electric line, or coiled tubing (CT), providing versatility and economy to meet multiple operational requirements.

This actuated tubing perforator eliminates logistical challenges associated with using explosives, is health, safety, and environment (HSE) and user friendly, and helps reduce rig time by minimizing missed runs. It is compact and heli-lift compliant for portable, rapid deployment and has no risk of damaging annular tubular or casing. Relying on the dependable performance of the tool to provide power, the actuated tubing perforator has proven to be a safe, reliable, and cost-effective means of punching production tubular for circulating purposes.

Acquiring, moving, storing, and handling explosive-based equipment can be very difficult and time-consuming. In many countries where regional security is a concern, the movement of explosives is a controlled activity and can often delay projects. Consequently, when an unplanned event occurs for which pipe severing with explosives is the solution, such as stuck pipe, the drilling rig team might be required to wait several days before performing this job. These types of occurrences are quite common, especially in highly active drilling areas. In some cases, this lost time is conservatively estimated to be more than USD 12 million annually for a land-based operation. It is easily plausible to incur triple these costs for offshore operations, noting that these cost estimates do not account for the revenue losses attributable to a delay in production of hydrocarbons.

Wells in the Middle East, both onshore and offshore, often require workover because of the highly corrosive environment to which the downhole equipment is subjected. During these operations, the downhole equipment frequently must be repaired or replaced. To maintain well control during these workovers, a single hole is often necessaryto allow the kill fluids to be circulated. Traditionally, these holes are created using explosives and a soft shot perforator or usingmechanical hole-punching methods. These types of solutions can also damage the tubing or casing, causing further issues. Workover jobs requiring a single hole to be punched are often economically compromised by delays in mobilizing explosives and because failures to perforate soft tubing are common when using traditional mechanical hole-punching methods.