Beyond Non-Magnetic Drill Collars: Why Gyro Directional Moduel Enable Near-Bit Placement?

Cutting Costs Without Cutting Corners: Eliminating Non-Magnetic Collars with Gyro MWD.

Challenge: Traditional magnetometer-based MWD tools face inherent limitations. Relying on the Earth's magnetic field, they must be placed inside expensive non-magnetic drill collars to avoid interference from steel drill pipes. This forces the measurement point far from the bit, compromising real-time accuracy and trajectory control.

Solution: The ER-Gyro-19 MEMS Gyro Directional Module uses the Earth's rotation axis as a north reference. Compact and robust, it can be integrated into shorter, standard tool joints and installed much closer to the drill bit.

Outcome: This eliminates magnetic interference issues and enables near-bit azimuth measurement—dramatically improving real-time trajectory accuracy, reducing positional uncertainty, and enhancing wellbore placement.

In directional drilling, bottom-hole assembly (BHA) layout follows a strict “steer – measure – transmit” sequence. While mud motors and bend assemblies change drill bit direction, MWD/LWD tools measure the resulting wellpath parameters such as inclination and azimuth. They must be placed after the steering assembly to capture the actual drilled trajectory.

The “Distance Lock” of Fluxgate Sensors

Conventional MWD tools, typically composed of triaxial magnetometers and accelerometers, require dedicated non-magnetic drill collars to shield them from magnetic noise. Due to structural and positional constraints, they are usually placed 60 ft (18.3 m) or farther from the bit—introducing measurement lag and reduced responsiveness.

The “Position Freedom” of Gyro Directional Module

Designed to replace fluxgate sensors, the ER-Gyro-19 incorporates high-precision triaxial MEMS gyroscopes and accelerometers. It delivers autonomous north-finding and maintains tracking accuracy in high-vibration environments:

Azimuth: 0.5°
Inclination: 0.1°
Toolface: 1 sec (L)

Its compact design (136.8 × 20.3 × 19 mm) allows direct replacement of traditional fluxgate sensors without modifying existing probe structures.

No long non-magnetic collars needed—it can be housed in a smaller non-magnetic sleeve and placed much closer to the bit within the BHA.

Core Advantages of Near-Bit, Non-Magnetic Measurement

✅ Higher Accuracy – Closer to the bit, the ER-Gyro-19 captures trajectory changes in real time, eliminating deviations caused by measurement lag.

✅ Extended Drilling Applications – Performs reliably in magnetically complex environments (e.g., near casings), enabling operations in previously challenging formations.

✅ Improved Efficiency & Cost Savings – Reduces or eliminates the need for costly non-magnetic drill collars. Enhances drilling success rates, mitigates operational risks, and supports better reservoir recovery—delivering significant economic value across oilfield development.

Ready to achieve precise, real-time wellbore placement without magnetic limitations?Contact us today to learn how the ER-Gyro-19 Gyro Directional Module can transform your directional drilling performance.