L&L Special Furnace Company received an order for a car-bottom furnace from a manufacturer of pipes, tubes and fittings located in the southeastern United States. The gas-fired furnace, scheduled for delivery in the fourth quarter of 2021, will be used for normalizing various steels and specialty alloys at temperatures up to 2200°F (1200°C). It will also be used to preheat, stress relieve and temper various steels and large pipe fittings. Working dimensions are 48 inches wide x 48 inches high x 120 inches deep, and uniformity of ±25°F (12.5°C) or better is expected throughout the work zone.
The furnace utilizes six medium-velocity burners that fire over and under the load. The furnace car moves in and out of the unit on railroad-type rails. The door is mounted to the car and is motorized with all required stops and clearances. The side seals are pneumatic and seal to the car bottom once the car is inside the furnace. Castable piers provide support for a maximum 10,000-pound load, and the furnace is completely insulated with ceramic-fiber modules.
The furnace is controlled by a Eurotherm Nanodac program control with two slave units. Three-zone control is provided to promote uniformity, and over-temperature protection is provided along with a six-input paperless chart recorder and jack panel.