Heat Treatment Furnaces
Forged
Rolls (UK) Ltd gave Northern Combustion Systems the contract to design and build
a roll hardening and preheat furnace.
N.C.S engineers came up with a unique design; consisting of two vertical, circular, tower furnace chambers, measuring approximately 6.4 metres high x 1.5 metres diameter. Each chamber will accept a single roll loaded in the vertical plane, with each roll weighing up to 15 tons.
One tower was designed as the heating (hardening) unit, and tangentially fired with fifteen Tempest high velocity burners in five zones. Northern Combustion Systems' unique design then allowed the preheat furnace to be unfired, with the exhaust products from the heating furnace being utilised to preheat the roll in the preheat chamber. Motorised flue dampers were integrated into the system, to ensure correct temperatures in each of the chambers. Final flueing from the preheat chamber was then taken out of the building.
Great
fuel savings were made, due to having preheat facility in an unfired furnace
chamber.
Temperatures
are in the range of 400șC for the preheat unit and 1000șC for the hardening
furnace. Uniformity of ± 5șC was achieved.
Fully programmed modulating
temperature control, temperature recording, and flame control was provided and
housed in a free-standing panel.
Smaller of 2 off 'CLAM SHELL' furnaces designed and built for a large Sheffield industrial group.
The furnaces are mainly fo annealing and heat treatment of steel ingots.
High velocity burners fire the furnaces which are capable of temperatures up to 1180șC and are on a pulse fired control system. Temperature uniformity conforms to Rolls Royce Specification.