How to Standardize an Offshore Drilling Rig Asset Hierarchy to Improve Data Quality and Accuracy

Benefits of Standardizing Drilling Hierarchies

A complete and accurate asset hierarchy is essential in maintaining an up-to-date representation of a drilling rig, and business advantages are realized when a hierarchical structure is developed. A correct hierarchy enhances various initiatives and tasks that are performed by narrowing analysis down to the functional location. Such initiatives include Failure Mode and Effects Analysis (FMEA) as well as Root Cause Analysis (RCA).

Work Management activities are also positively influenced by a standard and accurate hierarchy. Predictive and preventive maintenance and the spare parts required can be written to the exact asset requiring work, providing traceability of the work history. Maintenance strategies can be created once and applied on equipment that is similar between the platforms. Alternatively, once the correct spare parts are loaded into the hierarchy, inventory can be easily managed, producing a cost advantage by sharing parts between platforms, rather than requesting new purchase orders with the vendor. Another advantage of generating a standard hierarchy is the familiarity of the rigs for the drilling contractor and operators. The hierarchical structure should combine the function of equipment owned by the business with the knowledge of the Operators.

Drilling rigs will differ from platform to platform and from one type to another (e.g. Spar vs. Semi—submersible). However, the main systems at the upper levels in the hierarchy will, for the most part, remain the same.

Standardizing your drilling systems will help ensure that your asset hierarchy is accurate and complete. Additionally, having the same systems and sub-systems across different rigs will provide a measure that you have the right number of locations present.

Standardizing Your Primary Rig Systems (Level 4)

When dealing with different types of drilling platforms, a general hierarchical structure can be put in place at the high-level equipment systems. While the rigs keep different equipment and work with different vendors, the rigs will have a similar build of main components. A drilling hierarchy can be created with 10 primary systems to break up the major components.

A proper drilling hierarchy will include the following systems directly under the rig level:

Critical Secondary Systems (Level 5)

The secondary systems critical for operation on a drilling rig can be built almost identically under the primary systems.

Systems that fall into this category include the Drilling, Blow Out Preventer (BOP), Transport Handling, and Auxiliary Support System.

Offshore drilling rig BOPs are typically mounted below the rig deck, but subsea BOPs that are connected to the well head are another BOP type that are utilized offshore. The standardization approach listed as an example below took both types of BOPs into consideration:

Varying Level 5 Systems

The set-up of certain systems will be contingent on the specific build of the rig being developed. The development of a Power Associated system will differ for each rig depending on how the rig receives power. For example, a rig that generates its own power will need a system to store the generator and related equipment. The Safety Quality systems will maintain all safety equipment that needs to be tracked, including firefighting equipment and eye wash stations. Auxiliary equipment, including the Rig Air and Drilling Water Systems, should be children of the Auxiliary Support System. A Third Party System will also be different for various rigs. Any asset that is maintained by the preferred vendor will need to be kept in this system so that work management can be tracked properly on the platform and by the vendor.

There are systems that may be implemented to capture different places on the rig that are not operational or safety critical, but still need to be maintained or tracked. The Accommodations and Office Storage systems are meant to store the equipment in the warehouse and offices on the platform. Commodity items can be assigned to the work orders that are generated to the equipment in this system.

The Miscellaneous System is straightforward in its purpose. This system is created to store data for spare equipment and consumable equipment.

Specifying a ‘standard’ below level 5 provides minimal value due to the variations in different types of rigs and the equipment that is utilized.


Recently, Sullexis worked to create a standard hierarchy for two drilling rigs in the Gulf of Mexico for one of our clients. We analyzed thousands of pieces of equipment to make sure they were located at the correct levels within the CMMS. This was made possible by a custom software tool, the Asset Hierarchy Editor, developed to view the hierarchy in an expandable tree format.

Before Sullexis’ hierarchy cleanup, maintenance and the spare parts required to perform the maintenance was often being put into the CMMS at the wrong levels in the hierarchy. This was often because the correct assets were stored incorrectly in the hierarchy or missing entirely from the CMMS. These inaccuracies created a lack of trust in the data and reduced the effectiveness of reliability initiatives and maintenance activities.

We needed to create clean, accurate hierarchies for both drilling rigs so that our client could effectively manage their equipment. To do this, we decided to create a standard hierarchy to compare the hierarchical data in the CMMS to.

The standard hierarchy that was developed allowed the for the identification of critical gaps in the CMMS. Once this exercise was complete, it became clear which assets were completely missing from the CMMS and were critical to the rig’s performance. For example, one platform was missing functional locations for Power Tongs, a tool used to enhance the safety and efficiency of drilling operations. This gap was addressed by managing an offshore walk-down of the equipment, capturing all relevant equipment data, and importing the data into the CMMS.

While all Drilling rigs differ from platform to platform, the Primary and Secondary systems will, for the most part, remain the same. The standardization that was completed with the data from a rig on a Floating Spar platform and rig on a Moored Semi-Submersible platform proved valuable in validating existing assets and identifying gaps in the hierarchies that needed to be addressed.

Interested in Learning More?

If you would like more details on the standardized level 4 and 5 hierarchy that Sullexis has created please request a copy of our white paper “Developing Equipment Relationships within a CMMS” by emailing [email protected], the Asset Hierarchy Editor software mentioned above is available as a SharePoint application, and we’d be happy to walk you through its use. Please refer to our Case Study “Asset Hierarchy Fit for Purpose” to learn more about this tool.