Wave Propagation Resistivity Sub (WPR™)
APS's WPR sub is a spatially compensated, dual frequency (400 kHz & 2 MHz), dual spacing device designed for wireline-equivalent Logging-While-Drilling (LWD) and Measurements-After-Drilling (MAD) services in all well types. Applications include geosteering, correlation, pore pressure trend analysis, casing point selection, wireline replacement, logging while tripping and logging with and without the flow switch enabled (for air- and foam-drilled wells).
WPR's symmetrical design, with centrally located receive antennas, provides real-time compensation, eliminates invasion effects due to measurement delays, and improves accuracy by canceling variations in receiver channels.
WPR operates in all mud types including oil-based and salt-saturated and provides real-time resistivity with flexible transmission formats. High-resolution data is stored in downhole memory which can be retrieved and processed during trips.
APS provides a complete set of software-enabled borehole corrections and applications with WPR, including a dipping bed model for geosteering.
APS offers a Pressure-While-Drilling (PWD) option for 4.75 in., 6.75 in. and 8.0 in. WPR.
WPR General Specifications
Tool Sizes & Maximum Dogleg Severity
| "Tool Size" | Borehole Size | Maximum Dogleg Severity | Connection | |
|---|---|---|---|---|
| Sliding | Rotating | |||
| 3.5 in. (89 mm) | 4.625 - 4.75 in. (117 - 121 mm) | 40°/100 ft (70°/100 ft with flex-joints for short radius wells) | 16°/100 ft (25°/100 ft with flex-joints for short radius wells) | 2 7/8 AOH |
| 4.75 in. (121 mm) | 5.625 - 6.125 in. (142 - 165 mm) | 25°/100 ft | 13°/100 ft | NC38 |
| 6.75 in. (172 mm) | 8.375 - 9.875 in. (213 - 251 mm) | 24°/100 ft | 10°/100 ft | NC50 |
| 8.0 in. (204 mm) | 12.125 - 14.75 in. (308 - 375 mm) | 15°/100 ft* | 8°/100 ft* | 6 5/8 Reg. |
* Estimated
Mechanical and electrical connections and interface to APS SureShot™ MWD
- Resistivity sub is a node on the SureShot RS-485 bus
Power requirements
- Low operating power for maximum battery life
- Designed to run on 2x/3x batteries (10 cell DD) or 0x/1x/2x battery and turbine alternator
Tool Programming and Data Dump port
- Hatch cover for easy access via an intrinsically safe connection to allow tool programming and memory dump. Memory data dumps and tool programming can also be performed when the tool string is disconnected from the resistivity via the tool string lower end.
32 MB integrated FLASH memory
Download the WPR Sub TDS to view detailed Product Specifications.
TOP OF PAGE // Specifications subject to change without notice.
Wallingford 
