An Introduction to the "MUDLOC EQUALISER" with Dart Landing Sub.

The "Mudloc Equaliser" Under-Balance Hydrostatic Drilling Control System, designed by Specialist Drilling Tools Limited, has been designed to deal with the problem of pumping out M.W.D. surveys while drilling in wells where annular losses are encountered and also permit total pressure control integrity within the drill string, while tripping both in and out of an underbalanced well.

The system incorporates the highly successful patented "Mudloc" Mud-saver valve which is interconnected to a nitrogen charged cylinder that can be pre-charged to equal or exceed the hydrostatic head required within the drill string when there is a requirement to pump out the coded pulse through the mud column when utilising a typical M.W.D. tool.

A Pumpdown Dart provides the ability to lock the Equaliser in the open position if desired, to trip out of the hole.

The "EQUALISER" immediately shuts off any U-tubing effect from the drill string as soon as the circulating pumps are shut down, thus guaranteeing the drill string remains full of fluid while surveys and connections are being carried out.

The tool also has the ability to provide safe tripping both in and out of wells that are drilled utilising a rotating head and the well bore is constantly pressurised. The running of the "Flapper Valves" and similar tools for pressure control can be totally eliminated. The system can also provide the capability of monitoring well pressure through the drill string if required.

The "MUDLOC EQUALISER" is one simple tool that is ideally run below the survey tool or just above the drill bit, preventing the loss of drill string hydrostatic pressure.

The "MUDLOC EQUALISER" can also be adapted to run Liners and Completion Assembly in wells that have losses or are prone to "Formation Breakdown" in the annulus during the running of assemblies into the well bore.