TF Brochure.Gary - Flipbook - Page 20
Interlocks & Accessories
Opening valves in the incorrect sequence can
cause possible hazards to operators, the plant and
environment whether through the escape of
harmful substances, unintended mixing of chemicals,
accidental isolation of pressure relief valves
and similar.
Valve interlock systems are designed to ensure
that valves and ancillary equipment can
only be operated in the sequence
pre-determined by the system
designer. This is achieved with
locking devices that only
release keys when the valve is in a particular
position, usually fully open or closed, and then
For example we have supplied a combination of
mechanically lock the valve in that position.
both two and three port valves and interlocks for
Once released the key can be taken to the next
tanker fill points. A typical application may require
valve in the sequence.
a drain valve to be open to land drain when not in
use and diverted to a spill tank when in use.
This simple sequencing by means of the transfer of
keys is known as “interlocking” and is accepted by
Popular additions are extended valve spindles
safety, insurance and standards authorities as the
allowing operation of valves in lower bunds/pits as
most reliable and cost effective way of protecting
well as with some systems the option of cabinet
valve sequencing. By working with Safi and our
locks and visual key cabinets.
other valve and interlock partners we can offer
solutions tailored to your specific design brief.
For mission critical manually operated valves that
may be difficult to open due to their size, location
or simply impacts of age and use there are several
tools specifically designed to make these actions
not only quicker but also safer. Examples include a
portable drive actuation kit where a valve or bank
of valves can be fitted with a special mounting that
can be triggered by a single portable pneumatic,
electric or battery operated tool. Another solution
to this problem is provided by the pneumatically
operated power wrench which uses a simple drive
plate attached with U-bolts.
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Process Engineering Supplies
