At-Bit Gamma – PayzoneTracker

The PayzoneTracker is the latest generation of at-bit tool system designed and developed for placement of long laterals in shales or thinly bedded payzones.

The PayzoneTracker* brings sensors as close as 12 to 16in from the bit, allowing well trajectory adjustments to be made immediately, a significant improvement on standard MWD and/or LWD tools that usually are tens of feet behind the bit.

The new system can work in various types of mud, including OBM. With an At-Bit sub length of 35in (89cm), the PayzoneTracker* best preserves the bit steerability compared to any other at-bit tool on the market. The EM short-hop receiver can be spaced apart from the at-bit sub by 60ft (18m) or more enabling data transmission across the motor.

The PayzoneTracker* offers extended operation times of up to 200hrs in typical runs. Measurements include continuous inclination, in both sliding and rotating modes and 16-sector gamma readings. The EM short-hop receiver has been paired with the popular MWD systems on the markets.

Four quadrant gamma measurements and several other parameters are available real-time for transmission to surface via mud pulse or EMWD.

The PayzoneTracker* tool is available in both 4.75” and 6.75” sizes.

The nominal temperature and pressure ratings are 150°C and 20,000psi. Higher temperature and pressure ratings of 175°C and 25,000psi are also available.


  • Long lateral drilling in shales
  • Thinly bedded payzones
  • Immediate casing-point detection (reduction of drilling rat-hole)


  • Continuous INC while sliding or rotating
  • 4-quadrant Gammas for realtime transmission
  • 16-sector Gammas for memory
  • Bit RPM measurement
  • Measure point 12-16in to bit
  • At-bit sub length 35in.
  • Rated at 150°C/20000psi (175°C/25000psi option)


At-bit Sub

Tool Size4.75 in.6.75 in.
Length35 in.35 in.
Nominal OD5.0 in.6.75 in.
Max OD5.25 in.7.0 in.
Max ID1.313 in.2.375 in.
Connection PIN Up / BOX Down3-1/2 REG (IF option) / 3-1/2 REG4-1/2 REG (IF option) / 4-1/2 REG
Yield Strength15,140 lbf-ft29,900 lbf-ft
Make-up Torque12,000 lbf-ft24,000 lbf-ft
Max DLS Rotating15°/100ft8°/100ft
Max DLS Sliding30°/100ft16°/100ft
Max Downhole Drilling Torque12,000 lbf-ft24,000 lbf-ft
Max RPM (Downhole)250 RPM250 RPM
Max Flow Rate340 gpm750 gpm
Max Operating Pressure20,000 psi20,000 psi
Max Operating Temperature150°C (175°C option)150°C (175°C option)
Max Operating WOB25,000 lbs50,000 lbs
Max Sand Content1%1%
Max Number of Recuts44

Receiver Sub

Tool Size4.75 in.6.75 in.
Collar Gap Length35 in.35 in.
Collar Gap Max OD4.75 in.6.75 in.
Collar Gap Connection3-1/2 IF4-1/2 IF
Collar Gap Yield Strength18,000 lbf-ft34,000 lbf-ft
Collar Gap Make Up Torque12,000 lbf-ft24,000 lbf-ft
Receiver Electronics Housing OD1.875 in.1.875 in.


Inclination @ Bit
Range0 – 180 degrees
Repeatability±0.2 degrees while sliding or ±0.5 degrees while rotating
Measure Point to Bit12 in
Azimuthal Gamma @ Bit
Range0 – 1,023 AAPI
Number of Sectors16
Measure Point to Bit16 in.

Battery Life

Nominal Operation Time (Azimuthal Gamma only)Up to 200 Hours

Recommended Operating Parameters

RPMMax 200 for minimum fatigue
Formation Resistivity2 -200 ohmm for optimal short-hopping
Mud Resistivity1 ohmm or higher
VibrationMax 20 Grms, 50-1,000Hz
ShockMax 500 G, 0.5ms (z-axis), 1,000 G, 0.5ms (x- or y-axis)

Running Below a Mud Motor¹²

Tool Size4.75 in.6.75 in.
Max Bend Setting1.50º1.50º
Max DLS Rotating15º/100ft8º/100ft
Max Surface RPM6060
Max Mud Motor RPM180180

¹ Do not run any motor stabilization with Inc @ Bit sub
² WOB capacity of most mud motors is higher than Inc @ Bit sub