Developed from field proven components, the system is based on the integration of Sonardyne’s USBL acoustic positioning technology and BOP-mounted transponders fitted with high resolution inclinometers. This provides clear and unambiguous data on the vessel’s position and riser angle status.
The monitoring system comprises of four key elements; a Navigation Controller and Computer for controlling the transmission and decoding of acoustic signals, a vessel based transceiver which acts as an interrogator/receiver and responds to commands from the Navigation Controller, and a pair of DPTi transponders; one fitted to the riser and one fitted to the BOP.

On command from the Navigation Controller one of three angles can be measured; the Riser, the BOP or Differential Riser/BOP angle. The angles are measured and transmitted to the surface using acoustic telemetry. The data is decoded by the transceiver and transmitted to the Navigation Controller which uses the elapsed time from command transmission to reply and phase comparison to enable the vessel’s position relative to the BOP and riser to be determined.

The system recommends a bearing for the rig to steer to in order to minimise riser inclination relative to the BOP.

The MRAMS software is simple to learn, set-up and operate and allows users to achieve immediate success and get to work without delay or additional stress, which is often associated with new systems.

Features -Type 7842

• Developed from field proven Sonardyne components
• Helps prevent costly damage to riser and BOP by accurately monitoring differential angles and the rig's position relative to the wellhead
• Provides clear information to users in order to maintain riser angles within operational limits
• Integrated USBL acoustic positioning for DP reference
• Designed for deep water operations