Gamma Ray Tool


Enables calibrated cased-hole formation evaluation and correlation


Applications

  • Correlation to formation and wellbore tubulars
  • Shaly formation evaluation


Features and Benefits

  • Combinable with
    • Cement bond logs to fully understand zonal isolation
    • CCL to provide baseline completion correlation


Tool Description

The Weatherford gamma ray tool is compact, robust, and accurate. It precisely measures natural gamma-ray flux in a wellbore.


Specifications

Ratings and Dimensions

Maximum temperature

350°F (177°C)

Maximum pressure

15,000 psi (103.4 MPa)

Outside diameter

1.69 in. (43.3 mm)

Length

28.3 in. (719 mm)

Weight

12.7 lb (5.8 kg)

Min casing/tubing OD

2.38 in. (60.5 mm)

Max casing/tubing OD

7.0 in. (178 mm)

Tensile strength

Tension: 65,000 lb
Compression: 130,000 lb
Torque: 150 ft-lb

Measure point

6.4 in. (163 mm)

 

Borehole Conditions

Logging speed

Recommended: 60 ft/min (18.2 m/min)
Maximum: 100 ft/min (30.5 m/min) at 0.08 ft (.02 m) sample rate

Tool positioning

Centralized | eccentralized

 

Hardware Characteristics

Sensor type

Thallium-activated sodium iodide crystal

Transmission type

Analog, pulse, or telemetry

Data rate

20 frames/sec at 20 kHz

Combinability

Radial bond tool, cement-bond log, temperature

Connections

GO top /GO pin bottom

 

Electrical

Voltage

100 V DC

 

Measurements

Principle

Natural gamma radiation

Range

0 to 10,000 counts per s

Resolution

6.0 in. (152.5 mm)

Accuracy (1SD)

± 5%

Sensitivity

Approximately 0.998 counts/s per API unit

Primary curves

GR (API)

Secondary curves

Head voltage, internal temperature (telemetry only)

 

Calibration

Primary

Houston API pits

Wellsite verifier

Thorium blanket

Gamma Ray Tool

Reach out to optimize reservoir performance

Please fill in the form below for more information on our comprehensive and high-resolution technologies. You will hear from one of our wireline representatives shortly.