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TELGE  ROAD, HOUSTON, TEXAS  

FURNACES

These 2150 °F maximum operating temperature furnaces are hydraulically operated tip-up furnaces with a maximum load capacity of 36,000 pounds.  These furnaces are each equipped with three IGE axial flow high temperature fans driven by high efficiency 3 hp motors.  The fans provide 40,000 cfm of circulation to insure temperature uniformity and increase heat transfer rates. The speeds of these fans are controlled by variable frequency drives that are governed by the temperature of the furnace.  This provides for maximum uniformity and protects the fans at higher temperatures.

Each furnace has two (2) 5MBTU FUELSMARTÔ combustion system. This system features digital control of the fuel/air ratio that provides control of furnace atmospheres, minimizes fuel consumption and lowers power consumption.  These burner systems feature Eclipse combustion components for ease of repair and utilize a positive displacement fuel metering system with digital control interlocked with the speed control of the combustion air blowers.   This burner system exceeds the required 400oF/HR-heating rate for a maximum load weight to the maximum temperature.  The furnaces are provided with 2 zones of control. 

The furnaces are designed to handle a load with dimensions of 35 ft long, 8 ft wide and 2 ft high. Furnace uniformity is  +/- 15°F.  Furnace internal dimensions are 37 ft long, 10 ft wide and 6 1/2 ft high.  The furnaces are constructed of 3/16-inch steel plate reinforced with suitable structural members to provide a ridged casing.  Furnace pressure is controlled with a single motor, operating dampers on the twin flues.

The twin hydraulic cylinders for operation of the furnace tip mechanism are serviced by a central hydraulic system with one reservoir, two 7.5-hp pumps, and two accumulators.  The accumulators are used to provide a high furnace opening speed of 10 sec. with a low horsepower hydraulic pump system.  This one system can service up to four (4) furnaces.

The furnaces are lined with 2600 °F ceramic fiber modules with a lining thickness of 12 inches.  This is designed to provide a shell temperature of 172°F at 2150 operation.  The hearth is 12 inches thick and consists of 6 inches of a 2200 o insulating castable covered with 6 inches of 2600 oF high strength castable.  The perimeter of the hearth utilizes precast sealing blocks that are easy to replace.  The pier blocks are 18 inches high and arranged in 13 rows.  

CONTROLS

The computer in the control room provides furnace supervision and control. This computer communicates with the furnace temperature controls, the work manipulator, the quench tank agitator controls, the quench tank cooling controls and the furnace hydraulic operations.  The software provides interlocks to coordinate the operation of the furnace opening, manipulator movement and quench tank functions to insure proper implementation of quench cycle requirements.  In the event of computer failure, the furnaces may be operated from the local control panels.  The supervisory computer in the control room is a PC based system. The temperature controls are Honeywell UDC 3300’s.

Software integrates the control systems, provides order tracking and maintains the furnace operating records.  Furnace records include: time and temperature, load identification and furnace operation.  A digital multi-point recorder is provided for the furnaces to provide permanent records of all furnace and quench operations.

MANIPULATOR

The manipulator is used to load and unload the furnaces and to rapidly move loads from the furnace to the quench tanks.  The quench cycle time from furnace open to fully lowered in the quench is less than 60 seconds.  The work manipulator is constructed of structural steel beam and plate to provide a rigid assembly consisting of (three) 3 sections.  The lower carriage is provided with hydraulically driven steel wheels that ride on steel rails laid in the floor.  This unit can travel the full length of the furnace line.   The lower carriage carries the upper manipulator assembly that travels at a right angel to the lower unit.  The upper unit is also provided with hydraulically driven steel wheels that ride on rails on the lower carriage and at each end of the furnaces.  Mounted to the upper manipulator assembly is the lift arm mechanism that picks up the loads and lowers them into the quench. Two hydraulic cylinders power the lift arm mechanism. The lift arm assembly is provided with 14 lift fingers constructed of 8” wide flange structural beams.  The beams are bolted in place to provide for easy replacement.  A propane powered hydraulic unit is mounted on the lower carriage.  It is equipped with a generator system to provide both electrical and hydraulic power for the work manipulator.  A manual operator station is provided on the lower carriage to provide for local manual operation in the event of main computer failure.  Under normal operation, the main computer, through a radio link, directs the operation of the work manipulator.

QUENCH SYSTEM

The water and polymer quench tanks are reinforced structural steel construction and are located in a concrete pit.  The tops of the tanks are 42 inches above the floor and have a working volume of 55,000 gallons.  They are provided with load supports to allow the 36,000-lb. load to be left in the tank while the load manipulator is extracted for additional duties.  The dimensions of the tank are 37 ft. wide, 22 ft. long and 10 ft. deep.  The quench tanks are provided with six (6) agitators each and provide a velocity of 50 ft/min through the load area.  The agitators are mounted at the end of the tanks with draft tubes provided and distribute the flow up through the work.  Instrumentation and controls are provided for both automatic operations by the main computer or local operation in the event of computer failure.

The water quench cooling system consists of a 20 hp 1000 gpm. pump and a 375-ton Marley cooling tower.  This system provides sufficient cooling capacity to recover the quench temperature to 95°F in two (2) hours after the quench of a 36,000-lb load from 1650 °F.  The quench would recover in 2.5 hours from a 2150 oF quench.  The polymer quench cooling system consists of two 1000 gpm pumps, one Tranter SuperchangerÔ and a 375 ton Marley cooling tower.  This system provides sufficient capacity to recover the polymer quench temperature to 95 °F in 2 hours after the quench of a 36,000 pound load from 1650 °F.  The water and polymer quench systems have sufficient capacity to keep quenchant temperatures below 125 °F when quenching a maximum load from 2150 °F.

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