Hydrocarbon Processing - December 2021 - 73

Valves, Pumps and
Turbomachinery
J. YOUNAS, EFERT, Daharki, Pakistan
Aging pressure relief valves:
Are you managing history well?
The risks associated with the malfunction
or blockage of pressure safety
valves (PSVs) are significant, and operating
facilities invest heavily in preventive
maintenance (PM) programs to
mitigate the risks and ensure that PSVs
are functioning exactly as per design requirements.
Significant resources are allocated
to isolate, remove and transport
PSVs to a workshop so that they can be
returned to service as soon as possible
after inspection, testing and overhauling.
All field activities are controlled under
strict PM programs; however, one thing
that is sometimes overlooked is the preparation
of traceable historical records,
which is important to continuously optimize
and improve the program.
Troubleshooting and finding solutions
to some notable challenges of PSV
data management will not only increase
confidence in maintaining the integrity
of PSVs, but will also help to reduce PM,
saving cost and efforts associated with
their testing program.
Collecting clean and reliable data.
During root cause analysis (RCA) and
frequency review exercises, important
observations and findings are often either
overlooked or not recorded properly.
A report of a pressure vessel, piping or
a storage tank handling a non-critical service
is usually comprehensive (supported
by checklists and pictures) and approved
by the most-experienced site inspectors;
however, the report of a vacuum relief
valve installed on top of the same tank
may lack important observations and
might have been signed off by someone
less experienced in the group with insufficient
training.
Therefore, it is vital to establish a robust
mechanism onsite to ensure that
clean and reliable data is obtained from
inspection reports of PSVs. Regular audits
of records and proper training of
workers can help keep the system alive.
Extracting data from checklists
and forms. Large amounts of data
kept in printed or hand-written forms
require significant time and effort later
to visualize the data and observe trends.
Rather than writing reports by hand, it is
preferred that all reports and checklists
related to PSVs are filed directly into
the site digital database by each interface
involved, and printed certificates or
reports are generated through that particular
database itself, if required. This
will assist later in retrieving, filtering
and analyzing the data frequently and
in making strong and accurate business
decisions based upon technical inputs to
reduce cost and risk.
Some sites manage such records in
centralized MS Access or Excel data
bases, while others are using different
inspection data management software
(IDMS) for this purpose. Other maintenance
applications like Maximo or SAP
may also have such databases designed
for PSVs.
Inaccurate design and process
data. Maintaining accurate and updated
process and design data (FIG. 1) of all
assets-particularly PSVs-is the foremost
requirement of any process safety
management (PSM) system. A centralized
database link should be provided to
all involved in the PM of safety valves so
that information can be accessed readily.
This information should be always
kept updated. To ensure this is done, the
inspector for each PM incident should
be held responsible to verify this design
data and note remarks for action, if any.
If records cannot be updated immediately,
then such recommendations should
be tracked by IDMS or any other suitable
tracking mechanism used at the site.
Missing operating history and vendor
data. As per API-576 Section 6.2.4,
the operating history of each PSV since
its last inspection should be obtained
and should include pertinent information.
The following updated records are
important for proper PM execution and
to conduct studies related to reliability
or process safety:
* Vendor/manufacturer
maintenance manuals
* Spring range catalogues
* Information on upsets and their
FIG. 1. Sample process design data table for PRDs.
Hydrocarbon Processing | DECEMBER 2021 73
Hydrocarbon Processing - December 2021

Table of Contents for the Digital Edition of Hydrocarbon Processing - December 2021
