HOW TO AVOID
Amemorable story needs an
attention-getting beginning, a
compelling middle and a strong ending. Shortchange any of the three,
and the audience is bound to be disappointed. Similarly, a pressure
relief system needs good design,
proper installation and a systematic
program of ongoing maintenance.
Fail to give any of the three its due,
and you put products, facilities and
people at risk.
Poorly performing pressure relief
valves (PRVs) can result in loss of
production, loss of revenue, higher
operating and maintenance costs
and, potentially, catastrophic failure.
Our experience shows that between
75% and 85% of PRV performance
issues—including leaks, chattering
(rapid opening and closing), failure
to open at designated set pressure,
long blowdown (closing too far below
set pressure) and short uptime
between repairs—can be attributed
to improper system design, incorrect
valve installation, poor maintenance
practices, or a combination of these
It also is important to remember
that a PRV is a single component of
a larger system. Valves, tubing and
connections, and the operating system itself all must be working properly for the PRV to function to spec.
And as any valve manufacturer or
valve technician will attest, a problem with valve performance may not
be caused by the valve. Leaks, chatter, galling and valve body degradation can also be caused by problems
with other elements of the system.
This article will use real-world
case studies to illustrate some of
these common problems and why
IMPROPER DESIGN, INSTALLATION AND
MAINTENANCE OF SAFETY VALVES WITHIN
PRESSURE RELIEF SYSTEMS CAN LEAD TO
SYSTEM MALFUNCTIONS AND HAZARDOUS
CONDITIONS THAT PUT EQUIPMENT,
FACILITIES AND PERSONNEL AT RISK.
BY DAVID MELCHER AND WILLIAM TRAVIS