The document discusses using reliability modeling to optimize maintenance costs, safety, and operational performance. It proposes using a reliability model to calculate equipment failure probabilities based on limited failure data. This would allow balancing maintenance costs with safety and uptime. The model considers how maintenance affects reliability and costs. It aims to minimize under-maintenance and over-maintenance to reduce costs while ensuring safety and operational success. A proof of concept was developed using a drillship's blowout preventer. The goal is to bring the concept into a pilot project to demonstrate its benefits for maintenance planning and discussions between maintenance and operations teams.

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Offshore Europe 8 - 11 September 2015; Aberdeen.
Cost-balance through risk-optimized maintenance and improved equipment reliability
(Focus on hardware, not aiming to include human aspects or software).
Today’s challenging oil & gas market requires paying attention to a lower cost profile but with no compromise to
safety and operational performance. Prevention from over- and under-maintaining will result in reduced
maintenance costs while keeping safetyand operational performance levels attheir optimum resulting in optimal
balance between safety, NPT and costs.
Up to today however the objective to balance between cost, safety and operational success (or in reverse: Non
Productive Time (NPT)) has proven to be a difficult to achieve objective. A key to find a solution to make this
objective easier to achieve is to identify the common aspects in all these aspects. That key can be identified the
risk that is attached to these aspects.
We all wanta safe operation,as unsafety is an unacceptable risk; we all want a profitable operation without hick-
ups: no NPT - successful operation.
Both safety and operational success have in common thatthey prosper ifequipmentdoes not fail or break down:
reliable equipment leads to a higher uptime and a safe operation.
Reliabilityis only affected at two distinctmoments:during the design and during maintenance ifthat maintenance
is effective. We often cannotaffect the design so what’s leftis maintenance.Maintenance cost money but if done
correct it provides a more reliable equipment.
The cost of maintenance is heavily affected by how much over or under maintenance is executed, and reliability
is affected by effective maintenance: mitigation the effect of equipment failure modes or degradation.
In order to have a successful and safe operation we need to have reliable equipment.
We can assistin that by effective maintenance:no under or over maintenance and effective maintenance tasks to
mitigate the equipment’s failure mechanism. This result in effective (= less or no failures) AND efficient (= cost to
achieve the effect) maintenance: reliability informed equipment management allows for optimization between
maintenance cost,safetyand operational performance. A well-known main problem to startwith this is the limited
amount of available failure information.
Lloyd’s Register Energy developed an innovative Reliability Model that enables performance optimization for
safety and operational critical equipment in the most cost-effective manner including the ability to calculate
equipment failure probability from limited data sets. It can actually
Other aspects such as reliability forecast into a next well, spare parts optimization or workload optimization are
within the scope of reliability based equipment management, depending on what matters most for your
organization.
 The Risk Model operates more in the ‘effect ‘side of risk whereas the Reliability Model addresses the
“Probability of failure” side in Risk (Where risk is defined as effect * probability).
 The Reliability Model uses similar building blocks as the Risk Model that was made for several BOP’s
and by that means re-uses in a very cost effective manner what is already available. It is however also
possible to make a reliability Model from scratch, it will however than take longer to make one.
As a Proof of Concept (which it is right now) the annular close function from the DCL drillship was used for
reliability modeling, re-using the building blocks of the Risk Model made for that same BOP.
Optimizing maintenance to achieve safety and operational success bymeans ofreliable equipmentrevolves
around the costinvolved. Reliabilitymanagementis very suitable to optimize NPT and safety on a costbasis as
all are risk aspects and form a perfect balance beam: costof the risk of failure vs. the costof failure prevention.
A side achievementofmanaging equipmentreliabilitywith the ReliabilityModel is that it provides both
maintenance and operations departments an equal platform to discuss,compare and decide on maintenance or
operational priority.It brings a more level playing field to demonstrate the effect of maintenance,transl ated into
reliabilityand cost and shows the effect of reliable (or unreliable) equipmentfor operations also translated into
cost.
We currently try to bring the proofof conceptis currently broughtinto a pilot. This plot will allow for better
(hopefully) sales opportunityand could act like a demo.As we all know,having a working demo that people can
play with will bring more attention a potential sales.As the conceptis new and in an engineering stage we
acknowledge thatgrowing tis into a service will be a challenge.