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Motion compensation system equipment includes a variety of products designed to compensate for the vertical movement of offshore drilling rigs due to heave. Crown-mounted and direct-line compensators work to isolate the heaving motion of the rig from the drill string, while wire rope tensioners apply a constant tension to tension guidelines and podlines to prevent riser buckling. Our motion compensation system products are backed by a known history of customer service and dependability.
Crown-Mounted Compensators (CMC)
The crown-mounted compensator offers passive heave compensation for the drill string, aiming to keep a constant load on the bit while drilling. The crown-mounted compensator is mounted on top of the derrick crown beams and is used on conventional derrick/drawwork vessels.
N-Line Tensioner and Wireline Riser Tensioner (WRT)
The N-line riser tension system compensates for the heave, pitch, and roll of the vessel by using cylinders to apply a vertical force to the top of the marine drilling riser, while the wireline riser tensioner system compensates by applying a vertical force to the top of the marine drilling riser. This provides stability to the riser while controlling its stresses, displacements, and angles. Located on the drilling vessel near the periphery of the drill floor, tensioners provide tension to the riser while the floating drilling vessel moves in response to the wind, waves, and current.
Guideline Tensioner (GLT) and Podline Tensioner
The guideline and podline tensioners are passive and similar in-line tensioners. Often supplied as one combined project package, the main difference is the higher capacity of the podline tensioner: 12 mt maximum line pull compared with 7.5 mt.
MUX Cable Tensioner
MUX cable tensioners are used on-board floating drilling rigs to maintain a near-constant tension in the upper part of the MUX cable, which is the multiplexed power and communication umbilical between the rig and the subsea blowout preventer (BOP). This saves the MUX cable from heave-induced strain and material fatigue and ensures reliable command lines to the BOP.
Conductor Tensioner Unit (CTU)
Conductor tensioners are used on jackup drilling rigs to support the drilling conductor pipe, which connects the rig to the wellhead. This relieves the conductor of the full weight load and prevents buckling, vortex-induced vibrations, and material fatigue.
Direct-Line Compensators (DLCs)
The Direct Line Compensator system with an integral traveling block minimizes the effects of drilling vessel vertical motion (heave) on the fixed and rotating drill string and bit.
Drill String Compensators (DSCs)
The Shaffer™ Drill String Compensator is the most popular system of its kind in use today.
Module-Handling Compensator (MHC)
Our module-handling compensator is a safe and reliable solution for powerful splash zone and accurate subsea handling. Adapted to meet the individual needs of the operator, it allows operators to work for longer periods of time at high sea states, reducing downtime and increasing operational weather windows.
Compensated Coiled Tubing Lift Frame (CCTLF)
Our compensated coiled tubing lift frame supports completion and post-completion deployment for coiled tubing and wire-line operations offshore. Featuring a dual valve system enabling both primary and backup compensator mode, the CCTLF provides a unique level of functionality, performance, and safety.
Crown Mounted Compensation
Technical specifications for our standard CMC models
Technical specifications for our standard riser tensioners
Active Heave Drilling Drawworks (AHD)
Technical specifications for our AHD drawworks
Active Heave Dual Drilling Drawworks (AHDD)
Technical specifications for our AHDD drawworks
Offshore Product Reference Guide
A technical look at our offshore rig equipment product portfolio