Inferno Cannon

The Inferno Cannon is an immense pneumatically driven, six-barreled, air-cooled, electrically fired rotary auto-weapon that fires Heavy Bolter rounds. This weapon is commonly mounted on Warhound-class and Warlord-class Titans but they can also be mounted on the carapce hard points of an Imperator-class Titan. This weapon is also the primary weapon system of the Imperial Guard Malcador Infernus super-heavy tank. The Inferno Cannon is composed of three linked barrels that propels an a liquid incendiary chemical (Promethium, a petroleum-like jelly that can stick to a target and is very similar to the twenty-first century incendiary called napalm) that bursts into flames as it leaves the weapon. This weapon is primarily used as an anti-infantry weapon against ground troops on open battlefields or under heavy cover.

Operation
Promethium is expelled through the gun assembly by its own pressure and is ignited at the exit of the barrel through piezo ignition. This Liquid-operated flamer weapon system uses a large promethium tank to expel the liquid. For safety reasons, the promethium tank is behind the combustible liquid tanks in order to prevent being hit by a stray projectile of las blast. The promethium is fed into two tubes. The first opens in the promethium tanks, providing the pressure necessary for expelling the liquid. The other tube leads to an ignition chamber behind the exit of the gun assembly, where it is mixed with air and ignited through piezo ignition. This pre-ignition propane line is the source of the flame seen in front of the gun assembly. As the promethium passes through the flame, it is ignited and propelled towards the target.

Source

 * Adeptus Titanicus (1st Edition)
 * Apocalypse
 * Titanicus (Novel) by Dan Abentt