The most important factor when flaring occurs at a facility or platform is the integrity and reliability of the ignition system. Over the years many flare vendors have developed automatic electronic ignition systems both high energy as well as high tension. The common factor when working with these electronic sparking systems is that the system is only as dependable as the cable that is chosen.
During the last decade, Thermal Wire and Cable’s designs continue to operate in high energy and high-temperature environments within Flare and Combustions fields. TWC has developed multiple types of cable which outlast other similar cables. TWC worked with multiple Flare and Combustion companies to design and develop the SRGE “Flare Stack” cable as well as HEI cable, both of which have been proven to provide reliable with their automatic ignition system.
CST 450 – the Flare Stack Cable high-temperature solution
Due to the ever-changing requirements and specifications, Thermal Wire developed the CST 450. CST 450 has the same benefits as the SRGE cable with the ability to withstand higher temperatures (450C). The CST 450 cable is constructed to be durable, allowing the cable to face a multitude of climates, from the frigid air of Alaska to the harsh salt waters of the Gulf of Mexico. When properly installed, this proven cable has an excellent lifespan, and in some cases has outlasted the ignition rods.
Many of the malfunctions of flares and ignition systems are blamed on the ignition cable. These malfunctions are due to poor system installation practices. In many cases, the individuals who install the systems do not know what precautions to take when installing the cable.
TWC provides a waterblocking technique of insulated multi core conductors, very similar to what is done for Navy Shipboard cables. This proprietary technique pressure extrudes 200c silicone into the interstices (air voids) of the cable effectively preventing water ingress. This is very important for vertical runs. The majority of the reasons for cable failure is water ingress.
Examples of poor installations and suggested solutions are:
Not allowing for water to exit junction boxes and or conduit (low point drains are a MUST)
Water is a cable’s worst nightmare, and low point drains should be applied at the lowest point and bend. Also, if possible, it is suggested that the junction box nearest the bottom of the flex hose has a low point drain. In many cases, it is suggested to use a larger J-Box in which the cables enter the box from the sides, and exit the top leaving the bottom free to drain.
Not providing proper strain relief to oppose gravity (connections fall off ignition rods)
If strain relief is provided, the links at the flex hoses as well as the fire rods will not lose the gravity battle. Also, ring eye lugs are a viable option to secure the cable to the ignition wire.
Poorly constructed splices
The electrical current always finds the weak point and may strike in the J-Box rather than the ignition rod.
Cutting cables on sharp edges of conduit at bends and or openings
When pulling multiple cables through a small diameter, pipe bends can be difficult to navigate. Also, the tube edges should be free of burrs not to compromise the outer jacket of the cable.
When the cable is correctly installed, the automatic ignition systems can be as reliable as the old-fashioned FFG.