Operational assurance consultants to the global energy industry

6th Generation Drillship Rig Acceptance

ADC Energy Ltd (ADC) were awarded a contract by an Oil and Gas Operator for the provision of drilling rig acceptance services covering MODU Systems, Well Control Equipment, Dynamic Positioning Systems and Power Management, Safety Management, Environmental Compliance and Dropped Objects. These services were to be conducted onboard a 6th Generation dynamically positioned drillship prior to the commencement of drilling operations and spanned two separate inspection periods; the first being a shallow water phase conducted at anchorage and the second a deep water phase on the drilling location. The two stage approach was adopted to enable the witness of realistic operational scenarios. 

ADC were awarded a contract by an Oil and Gas Operator for the provision of drilling rig acceptance services; the objective of which was to assess the rig fit for purpose and to ensure it could be safely operated in accordance with applicable Client, regulatory and statutory requirements for the region. This project afforded ADC the opportunity to showcase their all4one approach to rig inspection and acceptance. 

ADC engaged all stakeholders early after contract award to discuss and agree the programme of acceptance inspection of the drill ship. This process considered the Operators drilling programme as well as being considerate to Client, regulatory and statutory requirements for the area of operations. The outcome from this process was a bespoke acceptance inspection document, derived from the functional design specifications and operability capabilities of the rig that was signed off and agreed by all.

This document was then distributed in a manner that proper planning, materials and resources could be made available when the acceptance inspection was to be conducted. The acceptance inspection was agreed to be conducted in two stages; one in shallow water and the other in deep water. In particular the deep water phase was to enable proper conductance of drilling equipment, power management and dynamic positioning system testing which is typically constrained in shallower inland water ways. 

ADC provided suitably qualified and experienced Specialists to be in attendance to conduct the inspections of equipment and subsequent witness of operational testing. 

The process was fully supported by the Client and drilling contractor; in particular the rig crew were found to be very competent and could not do more to assist the ADC team during the very comprehensive testing period.  The support provided can be  best illustrated by the willingness and timely response by the drilling contractor in closing non-conformances as they were recorded; a total of 95 non-conformances were raised during the drilling rig acceptance period with an associated distribution of 9 Critical, 27 Major and 59 Minor. At the time of the final close out conference call, there were a total of 0 Critical, 9 Major and 16 Minor non-conformances open. 

“Just a quick note to say thanks to you and your team for the excellent work carried out on the rig, your teams efforts has played a part in a successful start up with the rigs first month of operation being over 99.6% uptime. This is the reason ADC is the company of choice for rig audit services”.

drilling superintendent

During the conductance of the drilling rig acceptance inspection 9 critical and 27 major non-conformances (findings) were recorded. These included the incorrect operation of the slack wire function to the drill floor man rider, failure of the function to operate water tight doors from the bridge, the ROV system was inoperable due to the tripping of the power supply to the tether management system and the drillers choke control panel was found to be faulty. In each instance, each was satisfactorily addressed and closed by the ADC Specialists prior to departure. 

It each of the non-conformances (findings) mentioned above they referred to essential equipment and systems that were out with their respective functional design and were being inappropriately used to a point that may have led to loss of life, a serious injury or environmental damage. 

The significant lessons learnt was the importance of the development of a proper plan considerate to what was achievable in shallow and deep water, agreeing within all stake holders before commencement what was to be achieved, the resources required and the anticipated timings, maintenance of strong verbal and written communication between the focal points of the Client, Drilling Contractor and ADC during conductance and completing satisfactorily what was originally set out to achieve. 

Global Client List

ENI Total Energies Cnooc Conoco Phillips New Fortress Energy Petronas Carigali PCSB Tullow Oil
Beach Ithaca  Energy Harbour Energy Seadrill EnQuest Wintershall Diamond Offshore
Stena Drilling Exceed Noble Vaalco Woodside OSRL Azule Energy


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