Digital Ascension Distributed Temperature Sensing (DADTS)

KNOW YOUR WELL! Now with DADTS, you can not only listen, but also learn, and then use this knowledge to make corrections to your well that reduce operating costs and or improve recovery.

Digital Ascension Distributed Temperature Sensing

(DADTS)





Real Time Pressure Monitoring

Are You Listening?

Now Distributed Temperature sensing with DataWise’s DADTS system allows you to learn what’s happening in your well or reservoir in real time.  Your wells are continually telling you about themselves, but until now you really didn’t have a way to listen.  Now with DADTS, you can not only listen, but also learn, and then use this knowledge to make corrections to your well. Reduce operating costs and or improve recovery!  

Operating Principle
DADTS provides complete wellbore temperature profiles, repeatedly over time. Ramon scattering in optical fibers is used as the bases of the Principle technology. Short burst Laser light is pulsed down our DADTS cable optical fibers. Photons excite glass core molecules causing electron vibrational state change. Excited molecules give off light photons in the Stokes and Anti-stokes bands when returning to their normal energy state. Scattered stokes and anti-stokes wavelength light is collected back at the surface in time gated windows. Data processing converts the Stokes and Anti-stokes intensities returning within time gated windows to temperature.

Rapid Changes to Long –Term Temperature Profiles
Installing a DADTS cable and “listening” continuously enables you to identify transitional events as they occur in your wells. Having this information allows you to respond quickly, saving money and avoiding catastrophic events. Transitional events include:
 •   Production inflow rate changes by zone (if cable installed across all producing intervals).
 •   Changes to artificial lift conditions, including Gas Lift, ESP, PCP, or Rod pump
 •   Fluid level changes for pumping wells
 •   Leak occurrence in tubing, casing, or packers
 •   Gas breakthrough at point of entry
 •   Water breakthrough at point of entry

Information about Steady-State Well Conditions
Understanding your well involves knowing its temperature profile under steady state conditions. Steady-state complete wellbore temperature profiles can tell you the following information about your well.
 •   Single Phase Flow Profiles identifying Zonal contributions in Oil or Gas wells
 •   Flow Assurance monitoring of complete well under flowing conditions
 •   Observation well temperature profiles in Thermal Recovery projects
 •   Heavy Oil Thermal monitoring, SAGD, Steam-floods, Horizontal wells
 •   Artificial lift conditions including Gas Lift gas entry points, pump heat generation/dissipation, and annular fluid levels.

Operator Induced Short Duration Transient Events
Short duration transient events that cause changes to your well conditions can be used as a tool to assess valuable knowledge about your well conditions, including:
 •   Shut-in Surveys on Producing or injection wells including identification of cross-flow, gas breakthrough (JT cooling) locations, packer or tubing leaks, or fluid level changes.
 •   Leak Detection surveys to identify tubing, casing or packer leaks
 •   Steam-breakthrough surveys on producing Steam-flood producers.
 •   Artificial Lift evaluation surveys to evaluate ESP, PCP or gas lift systems
 •   Placement of pumped fluids such as chemicals, stimulations, and gas or steam injection.

DADTS Cable Deployment Methods
DataWise provides complete downhole installation services. Our experience includes the following types of installation methods:
 •   Permanent cables run strapped to production tubing and tailpipe
 •   Permanent cable strapped to Smart well completion equipment
 •   Permanent cables strapped to casing, cemented in place (directional perforating required)
 •   Retrievable cables run inside production tubular or open casing, similar to wireline
 •   Pushed or pumped- in Fibers run into pre-installed capillary tubing pathways
 •   Coiled tubing instrument strings run permanently in horizontal or vertical wells

DADTS Cables
DataWise offers a wide range of DADTS cables for oil and gas applications. Cable designs are made specific to your well conditions and are designed to yield a minimum 5 year life, optimized for minimum price. The following criteria are used to design your cable:
 •   Maximum wellbore temperatures anticipated for:
      •   Hydrogen barrier protection, including optical fiber glass chemistry
      •   Temperature resistance of Optical Fiber Coating material,
      •   Excess Fiber Length for differential length change
      •   External Cable Encapsulation, if requested.
 •   Well environment of cable placement for determination of proper metallurgy for corrosion resistance.
 •   Inclusion of EDPMS monitoring systems along with DADTS, built into the same cable
 •   Wellbore space requirement to select proper cable dimensions.

DTS Technology
DataWise’s DADTS Technology employs the latest in Dual Laser technology which reduces the effects of non-linear light loss and eliminates the need for double ended measurement.
 •   Temperature resolution down to 0.01 °C available on premium instruments.
 •   Instruments are available with optical budgets ranging from 12.1 dB on low end models to 23 dB on premium models.
 •   Instruments are available for multiple operating environments from offshore control rooms to outdoor land environments. Rack-mount, NEMA 4 and in ground packaging available. Environmental Temperature ranges from -20 °C to 50 °C.
 •   Multi-mode or single-mode systems available.
 •   Spatial resolution of 1 meter to 5 Km on all instruments and 15 Km on premium models.
 •   Data Telemetry Capabilities include MODBUS, TCP/IP Ethernet, DNP3, Relays, RS232 and more.

Visualization Software
Basic Data Visualization software is available on each DADTS system sold. Additional Data Visualization software, for use by engineers and swoperators (at remote locations), is available. This add-on software offers the ability to map temperature data to each wellbore being monitored, display multiple temperature traces simultaneously, review alarms, and replay data in a movie format.



Data Interpretation Service
Data interpretation can be provided on a consulting basis.