Survey Parameters Recorded:

Parameter

Range

Accuracy

Azimuth

0 - 360°

±1.00°

Inclination

0 - 180°

±0.10°

Toolface

0 - 360°

±0.5° - 3.0° configurable

Dip Angle

0 - ±90°

±0.10°

Magnetic Field

0 - 70,000 nT

±200 nT

Also Available

Gamma (360° or Focused), Temperature, Vibration Monitor, PWD, Depth Tracking

Technical Specifications

Transmission Type

Electromagnetic (EM)

Power

Lithium Battery - up to 120 hours per pack for EM

Flow Ranges

75 gpm (3.5” OD Collars) - 1100 gpm (8.25” OD Collars)

Pressure Drop

100 psi at 400 gpm

Diameter / Length

1.875” OD / 25ft + dependent on battery configuration and LWD options

Max Temp / Pressure

175°C / 20,000 psi

Surtron Technologies’ MWD-EM system combines the latest directional drilling technologies with electromagnetic data transmission. Introduced to the Australian CBM industry in 2002 these tools quickly replaced wire-line steering tools as the primary method utilised for directional control. The high speed transmission and data refresh rates achievable with MWD-EM ensure that the vital directional information required when drilling with high ROP’s is always on hand.

The MWD-EM system is normally situated behind the drilling assembly in a non magnetic collar providing high speed data transmission directly to the directional driller. Directional data is measured down-hole and transmitted through the formation to surface as electromagnetic waves where they are processed and displayed on the drilling console. Surveys are normally taken after each joint of pipe is drilled and while the next joint of pipe is loaded providing inclination and azimuth of the borehole. Unlike mud pulse systems it is not necessary to have ‘pumps on’ to transmit data to the surface. This means that a survey may be taken and the directional driller is ready to continue drilling immediately after the next joint of pipe is loaded.

Where used in conjunction with depth tracking the system offers a full suite of LWD sensors including Pressure while Drilling, Gamma, Vibration, ROP and Temperature. The MWD-EM is designed as a modular probe based system with flexible centralisers that are compatible with most drill collar sizes providing a one size fits all solution. In addition the system is also retrievable, an important feature should the drill string become stuck in hole.

APPLICATIONS:

The most common applications are:The highly flexible modular design suited to many applications:

• Horizontal & directional drilling for; 
  • Coal Bed Methane
  • Conventional Oil and Gas
  • Utilities Industry
  • Vertical pilot wells
• Slim-hole drilling for re-entry wells (1.875” OD Tool String)
• Short Radius Drilling (80°/100ft)
• Underbalanced drilling
• Lost circulation

ADVANTAGES:

• Fast data transmission up to 6 bits per second
• Probe based system compatible with a range of tubular sizes from 3.5” OD
• Retrievable and re-seatable, design reduces LIH risk and tripping costs
• Downlink enables re-programming without tripping
• On demand sensors and low power components extend battery life
• Battery stacking and switching ensures minimum downtime
• Modular design configurable with additional LWD sensors