JK Controls Ltd has the in house
capabilities to analyze, design and manufacture control and protection
client constructed a 2 km long 300 mm diameter high pressure steam pipeline to
supply energy to a chemical manufacturing plant. The source steam, superheated to 540
has to be de-superheated to about 350 °C for transport in the carbon steel pipes (yield temperature approx. 450 °C).
Under possible failure of the de-superheater the source steam would
reach the carbon steel pipe and cause a catastrophic rupture. High integrity protection is required to quickly isolate the line if
such an event should occur.
Controls staff designed and built high integrity multi-channel relay
protection systems to cover this and other potential fault events. Interlocked test circuits were incorporated to enable regular
validation of the trip circuits. This included invoking the first 10% of travel of the final trip valves
to check if the valves are still live. We also provided the on site expertise to install and assist with the
test and commissioning activities.
pipeline trip would cause severe disruption to the power utility boilers that provide
the source steam. JK Controls staff designed a sequence and modulating control scheme to
divert the pre-existing steam flow rate to a dump area whilst the boiler
conditions are being stabilized.
relay based sequencing schemes were designed and built by JK Controls. In this instance the relay logic was computer modeled to test the
design prior to committing it to hard wire assembly, to avoid the possibility
of costly corrective work.
Controls staff analyzed the de-superheater thermodynamics to optimize the
control valve characteristics to obtain control over a wide range of operating
conditions. Similarly the main pipeline split range pressure control valve characteristics were
carefully defined to cope with the very wide range of flow conditions
Boiler Control System
JK Controls are providing boiler control
expertise to a large power boiler manufacturer for design and implementation
of burner management and other control and instrumentation functions.