The Wel-lok M2M™ technology consists of utilizing a modified thermite chemical reaction heater to melt bismuth-based alloys downhole. The melted alloys have a viscosity similar to water, and a specific gravity 10 times that of water, allowing them to flow into the smallest areas of a wellbore without the need of any surface pumping equipment. As the alloys cool and solidify, they expand to provide a seamless gas tight seal that is non-corrosive and not affected by H2S or C02.
The engineers at BiSN have developed the unique core Wel-lok M2M™ technology to be specifically applied to the completions stage of the well. This is not a one tool does all solution, but a bespoke innovation which is adapted for annular sealing. Traditionally elastomer seals and cement have been used for decades to seal the annulus between casings. As many field engineers will testify, the elastomers and cement are known to have a high failure rate, having to be remediated using cement or resin squeezes. These are expensive, difficult and unreliable workovers.
The Wel-lok M2M™ TDAP (Thermally Deformable Annular Packer) is the new generation of metal to metal annular seals/packers. The alloy is placed in the well on the inner string during completion and is cemented into place. The unique BiSN design copes with the cementing process and still creates a gas tight metal to metal seal. After cementing the TDAP is set using a wireline activated chemical reaction heater, melting the alloy leaving a gas tight metal to metal seal. Due to the viscosity of the molten alloy being similar to water it will fill and seal the smallest of micro-annuli. The finished metal to metal seal is seamless.
Seals the annulus with advanced metal to metal technology
Gas tight seal without the use of elastomers
Utilises modified thermite chemical reaction heater to quickly melt bismuth based alloys
The melted alloy has the viscosity of water allowing it to flow into the area requiring sealing including micro-annuli in cement
Produces a seamless, gas tight metal to metal seal as the alloy expands when it solidifies
No mechanical moving parts once set
Available in a range of sizes to suit API & non API casings
Non-corrosive and not affected by H2S or CO2
Reduced downtime and costs for interventions
Reduced impact on the environment
Enhanced corporate responsibility
Reliable sealing solution
Extends the life of the well providing a long term seal
Reduced contingent liabilities
Easy to deploy in a single trip intervention
Temperature ranges up to 160 °C
The Wel-lok M2M TDAP™ (Thermally Deformable Annular Packer) was developed as a preventative tool to be run as part of the original casing string. It is run on an inner casing string and cemented into place. After cementing, the TDAP™ is set by running a chemical reaction modified thermite heater inside the casing to melt the alloy and create a gas tight seal in the annulus, eliminating the possibility of future casing vent flow when the cement in the annulus ultimately degrades and develops micro-annuli. If utilized in the design of the well, this tool can eliminate future expensive interventions and unreliable cement squeezes required to address surface gas pressure through cemented annuli.
|BiSN WEL-LOK M2M TDAPTM DIMENSIONS|
|TDAP SIZES||TOOL OD|
ALLOY (ft) (B)
|5 1/2" x 8 5/8"||7.88||4||10.8|
|5 1/2" 10 3/4"||9.8||4||10.8|
|9 5/8" x 13 3/8"||12.09||4||10.8|
|* custom sizes available|