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Contact Expert
Email: chris.cheng@cnpcusa.com
Phone: +1 (713) 972-6518
Address: 2901 Wilcrest Drive, Suite 600, Houston, TX 77042
Drilling Monitoring Sub (DMS)
The CNPC USA Drilling Monitoring Sub (DMS) monitors downhole drilling parameters to improve efficiency and performance. Measurements are recorded and transmitted in real-time via MWD Telemetry, allowing for optimized ROP and mitigation of shock and vibration—the primary causes of downhole tool failure.
Key Features
- Real-time BHA diagnostics
- Recorded and real-time mode measurements
- Compact design with scalable architecture
- Integrated real-time clock
Benefits
- Reduced operational risks
- Maximized drill efficiency and ROP
- Early detection of downhole dynamics problems
Sour Service Capability
The DMS utilizes high-strength, corrosion-resistant alloys including Inconel 718, P550, and Beryllium Copper. While standard elastomers offer partial resistance, specialized elastomers are available for $H_{2}S$ concentrations exceeding **20 ppm**.
Integrated Sensors & Data Acquisition
Pressure transducers and drilling dynamics sensors are integrated within a specialized collar. Measurement signals are processed using proprietary methodology to deliver both low-resolution real-time data and high-resolution post-run analysis.
Technical Specifications
| General Specifications | |
|---|---|
| Borehole Size Range | 8-3/8 in. to 9-7/8 in. |
| Nominal / Maximum O.D. | 6-3/4 in / 7-3/8 in |
| Nominal I.D. | 2 inch |
| Length / Weight | 114 in / 818 lbs |
| Thread Connections | Uphole: 4-1/2 I.F. Box | Downhole: 4-1/2 I.F. Pin |
| Collar Material | P550 Non-Mag SST |
| Auxiliary Materials | Inconel 718, BeCu |
| Elastomer (Standard) | FluoroCarbon 90D - Parker V0709 |
| Elastomer (H2S Service) | FluoroCarbon 95D - Parker V1238 |
| Operating Temperature | 32-347°F / 0-175°C |
| Max Operating Pressure | 25,000 psi / 172 MPa |
| Max Overpull (Tension) | 500,000 lbs / 2224 kN |
| Max WOB | 1,000,000 lbs / 4448 kN |
| Max DLS / Torque | 10 deg / 100 ft | 30,000 ft-lbs / 40,675 Nm |
| Measurements Performance | ||
|---|---|---|
| Property | Weight On Bit (WOB) | Torque On Bit (TOB) |
| Design Range | ±80,000 lbs | ±24,000 ft-lbs |
| Operating Range | ±100,000 lbs | ±30,000 ft-lbs |
| Accuracy / Repeatability | ±5% / ±1% | ±5% / ±1% |
| Resolution | 100 lbs | 200 ft-lbs |
| Property | Bending On Bit (BOB) | Drilling Dynamics |
| Range | ±100,000 ft-lbs (Design) | Vibration: ±30 g |
| Operating Range | ±85,000 ft-lbs / 10˚/100 ft DLS | RPM: ±333 |
| Accuracy / Repeatability | ±5% / ±1% | RPM Accuracy: ±1 |
| Resolution / Sample | 100 ft-lbs | Vibration Sample: 1,000 Hz |
| Pressure, Temperature & Data Acquisition | |
|---|---|
| Pressure (Bore & Annulus) | 0-25 ksi Range | 5s Sample | 0.38 psi Resolution |
| Temperature (Bore & Annulus) | 0-175°C Range | ±1% Accuracy | 0.01˚C Resolution |
| Downhole Memory | 16 Gb Capacity | 200 hrs Life |
| Electronics Power | 20-36 Volts Input | 90mA / < 5 Watts Consumption |
| Interface to MWD | RS485/232, or Custom |
| Data Acquisition Rates | 1,000Hz Sample | 3s Process | 5s Update Frequency |
| Mud Content Limits | Sand Content: 1% Max | LCM: No Limit |