Technical resources, definitions, and troubleshooting guides for the modern directional driller.
A comprehensive overview of downhole telemetry systems.
Read ArticleUnderstanding positive, negative, and continuous wave pulses.
Read ArticleWireless transmission through formation for air drilling.
Read ArticleThe mechanical heart of the MWD system.
Read ArticleFind answers to common failure modes and operational theory instantly.
Real-time downhole directional and gamma measurement system.
MWD focuses on wellbore geometry; LWD focuses on formation evaluation.
Inclination ±0.1°, azimuth ±1–2° depending on conditions.
Often beyond 20,000 ft depending on temperature.
Most: 150–175°C. High-temp tools: 175–200°C.
Heat, vibration, mud solids, electronics fatigue.
Rotational orientation of the tool relative to the wellbore.
Mud pulse, EM, or wired pipe telemetry.
Magnetic isolation for accurate azimuth.
12–80 hours depending on pulser load.
Debris, thick mud, torque spikes.
Inspect poppet seat, motor, flexshaft.
Mechanical drag or motor degradation.
Weight, viscosity, solids.
LCM blocks flow restrictors and bearings.
A helical torsion shaft transferring motor rotation.
Every run or every few runs depending on mud.
Flow stand, RPM tests, pressure amplitude checks.
Bearing wear or debris ingestion.
Use clean mud, inspect flow path, rebuild consistently.
Historical record of tool performance.
Active vs sleep time ratios.
Ensures survey accuracy.
Speed settings for different flow.
Comparing logs over time.
To detect internal shorts.
Place sensors away from steel.
Surface verification of pulses.
Verifying computer reads pulses.
Cool, dry, vibration-free.