This paper discusses on the new method of MWD surveying in drilling operations. It highlights the ability to take surveys faster than the conventional method while minimizing drilling risks. This resulted in a significant time reduction of the overall survey operations.
The MWD survey package normally requires the BHA to be stationary before it can start to acquire new survey data. Previous MWD survey systems monitored drilling fluid flow rate to trigger the MWD survey acquisition. This new MWD survey technique monitors rotation, optimising low noise detection, earlier. The new method takes less survey time, the pumps off time removed from the survey period.
This new method has been utilized in 4 out of 5 wells throughout the drilling campaign. The benefits can be clearly quantified from the comparison between the conventional and new approach. Based on the Drilling Mechanical Logs, the new method has proven to be able to shorten the surveying time by up to 80% compared to conventional. This translated to approximately 8.7 hours of rig time savings for the drilling phase of the project. Apart from time saving, it reduces stuck pipe risk by not having to stop pumping while also minimizing pipe stationary time. With the simplified survey operations, there is less likelihood of facing survey problems related to pump, signal and any other issues that may lead to the need of repeating survey.
Companies operating the exploration and production of oil, gas and water energy resources are continually looking for methods and techniques to reduce the time taken to drill and construct wells. The drilling phase is typically where there is a higher cost due to the drilling rig daily spread cost and the associated added environmental, health and safety risk aspects. Typically wellbore construction process is designed with a specified minimum tolerance for placing the wellbore inside the desired geologic zone or horizon, avoiding offset wellbores and geohazards and surveying the wellbore position sufficiently accurately to enable a relief well to be drill in the event of a well blow out.
Wells drilled during the recent five well campaign, offshore Malaysia have utilised this new method for taking surveys with reduced survey time as part of the new operator Operational Excellence and Drilling the Limit initiatives.