EOR (Enhanced Oil Recovery) helps to improve the average recovery factor for typical mature fields around the world up to 30-40%, extending worldwide reserves to a bit more than 50 years supply of oil. The different techniques used, including Water & Gas injection (WAG), polymer flooding, flow diversion, the use of surfactants, and steam injection for heavy oils (both Steal Assisted Gravity drainage – SAGD wells, and cyclic steam injection (CSS wells) will increase the life of a field. Sometimes oil and gas operators need to modify the injection/production profile, to switch from producer to an injector well, having first to cover unwanted perforations with a casing patch.
Saltel Industries offers a remedial alternative to isolate perforations with a thin-walled casing patch. Run with drill-pipe or coiled-tubing, Saltel Patch allows one of the best ID access to the well below (for packers, tubing anchors...) Saltel Xpandable Steel Patch seals effectively and holds significant differential pressures. ratings (See Xpandable Steel Patch for EOR)
Modifying injection profile
Many wells are completed and perforated, in both production and injection wells. During the life of well, the required profile might be reconfigured, as fluid levels vary, and EOR techniques allow modifying downhole parameters. It may be necessary to close off existing perforations, re-perforate in new zones, or change the injection profile. Covering perforations with Xpandable Steel Patch is an optimized EOR technique allowing to eliminate unwanted and expensive water production, to reduce gas production, and to avoid cross-flow (communication between 2 reservoirs). This technology is also suitable when converting a producing well into an injector (or vice-versa).
Casing integrity may be jeopardized due to corrosion, to mechanical failure, or to perforations to seal after cement remediation operations. If cement remediation requires casing perforations, then an expandable steel patch can be used to provide pressure integrity across the perforations. If casing pressure test cannot be achieved due to mechanical failures such as leaking DV tool or casing collar leak, a similar approach can be used to achieve pressure integrity. Operators need a reliable solution to cover up and isolate sections of the damaged casing, and to withstand at the same time high differential service pressure ratings, both internal and external.
Internal or external corrosion of tubings in the presence of water is a common problem during the life of the well. Most oil and gas production involves co-produced water, making corrosion a pervasive issue across the oil and gas industry. Moreover, age and presence of corrosive materials such as carbon dioxide (CO2) and hydrogen sulfide (H2S) can exacerbate the problem.
The inevitable exposure with production fluids can compromise the integrity of a tubing string. Either through mechanical fatigue, heat dilatation or corrosion, a leak can appear. For tubing sizes 4-1/2 to 13-3/8in, Saltel Xpandable Steel Patch can be run to repair corroded tubings (once installed the Patch given internal and external differential pressure rating vary depending on whether it is supported or not). Running a tubing Patch eliminates the need to pull out the completion string, and minimizes the non-productive time involved with a full workover operation.
Saltel Xpandable Patch is an excellent inner lining alternative for repairing corroded or eroded tubings, should they be even twisted, burst or bent. The Patch seals the corroded zone, ensuring maximum nominal and drift ID after setting. Saltel Patch provides effective sealing, even in out of gauge or worn tubings. Here the Patch sealing efficiency logically depends on the level of corrosion, and the elastomer skin thickness.
Well intervention Extending the life of producing wells
Saltel Industries offers a range of well intervention services based on a solid field-proven track record and experience to extend the life of producing wells, by improving performance and recovery of hydrocarbon reserves.
During the life of well, some downhole hardware might require maintenance, repair or replacement. When requested, operators usually turn to well intervention contractors. Well interventions can be split in two general categories: light or heavy.
Light well interventions address live well operations with pressure at the surface, to replace or adjust downhole equipment such as pumps, valve, or to collect live data on pressure, temperature and flow rates. Saltel Patches can be set to address casing integrity issues with a smart coiled tubing unit or a snubbing unit. The feasibility of the job will depend on the well configuration.
Heavy well interventions involve the interruption of the production prior to process major equipment changes. Also referred to as workovers, heavy interventions means replacing bigger hardware such as tubing strings and pumps that cannot be retrieved through light interventions. Prior to replacing tubing strings, the casing or tubing patch alternative can usually be sufficient to repair corrosion, leaks, or parted connections, and can even be used as a backup to squeeze cement or squeeze gels, depending on the application and the well configuration.
Specific heavy interventions may be performed to plug and abandon an initial producing zone, to reconfigure the well and produce from a secondary zone; these operations are known as recompletions. Saltel Xpandable Steel well Packers have already been used as a plug and abandonment solution and also as annulus isolation barriers in recompleted wells.
The parted casing is the result of a tubular exceeding its mechanical limits due to overpressure rates during stimulation, excessive loading, or tectonic movement.
In the case of a parted casing string, the separation usually occurs at the coupling, due either to a fracture, the stripping of the threads, the collapsing of the end of a joint, the expanding of the coupling, or two or more factors in combination.
A sudden loss of weight and a decrease in circulating pressure usually means the pipe has parted downhole. Care is necessary when pulling out of the hole after the tubing has parted since there is no BHA to prevent the broken pipe being pulled right out the stripper and a consequent loss of containment.
Benefits in repairing parted tubular with Saltel casing Patch
Sealing efficiency against the parted tubular. Once installed Saltel patch sealing design allows relative displacement. That means the parted section will slide around the patch without damaging the seal in case of thermal expansion of the tubular during production.
Excellent resistance to temperature cycling. Extreme high-temperature patches were installed with success to repair 7in and 9-5/8in parted casings in Canadian CSS (Cyclic Steam Stimulation) wells, where temperature cycling is essential. Saltel casing Patch confirmed strong resistance in CSS wells.
Optimized profile of the patch BHA to enter the parted section. The bottom of BHA has a good entry guide profile to reach setting depth, even in a parted section. This statement is valid only if the misalignment of the parted sections remains minimal.
Saltel Industries and Atteris have combined their expertise and technology to develop a range of new pipeline repair methods. This game changing technology is based on internally repairing a pipeline defect using Saltel Industries’ proven Expandable Steel Technology, combined with standard deployment techniques and equipment.
In many pipeline defect repair scenarios the internal patch repair technology enables a substantial reduction in repair cost, possibly avoiding the need for a diving support vessel, a hyperbaric weld spread, pipeline handling frames and mass flow excavation equipment.
The Saltel Expandable Steel Patch is made of a high quality corrosion resistant alloy sleeve covered with elastomers. The Patch can be run on coiled tubing or drill pipe from an access point several kilometers away from the target. At the pipeline’s defect location the Patch is expanded using Saltel Industries’ high pressure inflatable packer. Packer inflation pushes the patch against the pipe wall to activate the outer seals. Then the setting tools are extracted to leave a pressure resistant inner lining inside the pipeline.
We deliver a complete package including engineering, design, qualification, compliance, onsite management and installation. Installation is managed by highly trained Saltel engineers ensuring the success of every repair.
This method employs a pair of horizontal wells along the reservoir to produce the heavy oil. The upper well is continuously injecting high pressure vapor to heat the reservoir and reduce oil viscosity. At the same time, the heated oil drains into the lower well where it is pumped out. Even if the vapor pressure and temperature is lower than CSS wells, reducing thermal stress on the casing string, leaking couplings and casing failures can occur. We adapted our technology to propose a remedial solution able to withstand high temperature and to seal high pressure in “out-of-zone” part of the well while being cost effective for operators.
• High temperature conditions up to 300°C • Seal evenly at high and low temperature • Minimum impact on production rate to keep the well profitable • No ageing concerns of materials used • Cost effective solution
Saltel Expandable Steel High Temp Patch 300°C/572°F is a life of the well solution to repair thermal well with high pressure / high temperature conditions. The technology and the setting procedure are based on the standard SES Patch with some changes on the sealing design to fit the high temperature without using elastomer. (Our product was successfully qualified through SAGD conditions up to 300°C with no degradation detected).