WELL CONTROL READINESS
An example involves hydraulic wellbore
connectors. Some connectors should not
be locked with pressure exceeding 1,500
psi due to crushing effects that may be
imposed on the wellhead, BOP mandrel or
test stump. There are others that physical-
ly cannot be latched above a specified psi
because a relief valve has been installed
on the closing circuit.

Testing should also take into account
the OEMs’ allowable return flow for control
system valves. This has been discussed in
API Standard 53 committee meetings for
potential inclusion in the next revision
of the standard. Normal return rates have
been reduced by design improvements
(e.g., highly polished tungsten seal sur-
faces versus matte finishes on softer mate-
rials). Control system OEMs may produce
new designs that would lead to tighter
systems with less return flow.

Potential to reshape with
technology Collaboration and digitalization can
play a pivotal role in standardizing BOP
soak testing practices. By working togeth-
er within the API committee meeting
structure, operators, contractors and ser-
vice providers can develop a unified test-
ing methodology and recommended best
practices that consider the different BOP
configurations and unique requirements
throughout the industry. Digital tools can
streamline this process, making it easier
to apply uniform testing protocols across
various operations and regions.

In addition, digital applications can
be designed to perform trend analyses,
remove subjectivity from test results, and
help identify testing missteps (e.g., valve
alignment and trapped pressure in the
wellbore). Digital twin displays can facili-
tate collaboration and provide insights for
the stakeholders as they strive to protect
people, the environment and assets.

Standardization framework
Given the history of control system
failures, the industry has recognized the
need for enhanced testing measures, par-
ticularly in soak testing. Drilling contrac-
tors have been refining procedures and
monitoring techniques. This initiative
aligns with the specifications set out in
the 5th edition of API Standard 53 from
Figure 4: In same time frame as Figures 2 and 3. Utilizing client-specified system
pressure leak-off rate criteria, a passed test was seen after about 40 minutes.

December 2018. This edition introduced
the requirement for soak testing subsea
stacks prior to deployment. Specifically,
Table C7 emphasizes the need to validate
the BOP stack hydraulic circuits at the
highest pressures anticipated during well
control operations. The test’s duration is
per the equipment owner’s stipulations,
with the key acceptance criterion being a
visual confirmation of no leaks.

Standardized BOP soak testing should
encompass all aspects of the pre-deploy-
ment soak testing process, including test
step duration, pressure limitations, con-
figuration (mode) and testing conditions.

It should also consider the varying envi-
ronmental conditions in which BOPs are
deployed, as well as the different types of
BOPs and their specific requirements.

Path forward
The contributors of this article support
the development of standardized recom-
mendations for BOP soak testing for inclu-
sion in the next edition of API Standard 53.

This could be an informative annex that
will help reduce subjectivity in visual leak
verifications, leading to enhanced safety
and reliability performance industrywide.

Equipment owners would have the benefit
of shared best practices as a starting point
for their procedures.

Improving the effectiveness of pre-
deployment soak testing of BOP systems
will reduce risks directly associated with
its reduced availability to perform the
intended critical functions. In addition,
reducing unplanned BOP pulls will elimi-
nate risks associated with retrieval and
subsequent redeployment. This further
safeguards people and the environment.

A joint effort among stakeholders in
crafting this methodology will enable swift
and effective BOP assessments and stable
health KPIs, and further reduce subsea
NPT. The journey to improve the reliability
and performance in drilling operations
will not cease as we reaffirm our commit-
ment to improving industry standards of
performance and safety. DC
Reference: American Bureau of Shipping &
ABSG Consulting Inc’s Blowout Preventer (BOP)
Maintenance and Inspection Study Final Report
for the Bureau of Safety and Environmental
Enforcement., June 2013.

DRILLING CONTRACTOR • SEPTEMBER/OCTOBER 2023
23