HOMOGENISATION FACILITIES
SPECIFICATION FOR HOMOGENISING FURNACE
Utilities
FUEL Natural Gas, 300 Nm3/h
Pressure at entry, 300 mbar
Calorific value assumed 11.000 Kcal/Nm3 LPG
ELECTRICITY 380V, 3 phase, 50 Hz
COMPRESSED AIR 7 Bar
Furnace Data
INTERNAL LENGTH 6800 mm
MAXIMUM LOAD LENGTH 6500 mm diameter
NUMBER OF CIRCULATING FAN 3 x 30.000m3/h@125 mmWC
BURNER CONTROL ZONES 3
BURNER CAPACITY IN EACH ZONE 500.000 Kcal/H x 3
OPERATING TEMPERATURE RANGE 550-650 oC
DESCRIPTIONS
Furnace Casing
The casing would be fabricated from 5 mm mild steel plates fully welded construction reinforced with rolled steel sections to form a strong and rigid structure.
The furnace would be heavily insulated to reduce heat losses to a practical minumum and minimise the thermal mass for optimum efficiency and to cater for thermal cycle.
The sidewalls would be lined low resin mineral wool and ceramic fibre blanket to total thickness of 300 mm with overlapping joints and no voids.
After installing the insulation the furnace roofs and walls would be lined with press braked stainless steel panels clamped in position with channels held back to the outer casing on hook bolts. The system ensure minimal through metal contact and a very low casing temperature.
Door Operating Mechanism
The door would be fabricated from mild steel plates internally reinforced with steel sections, lined with insulation and clad with brake pressed panels similar to the furnace casing.
The vertical movement of door would be by means of an electric geared motor with integral brake.
The door would be suspended on two chains which connect to a balance weight via sprockets which are located on axles supported in bearing units on to the overhead structural steel frame.
When the door is in the “down” position a clamping system moves the door in a horizontal plane to form positive seal to prevent ingress of cold air into the furnace chamber. A ceramic fibre seal would be located around the periphery of the door.
Recirculating System
The circulating fans would be mounted in the furnace side wall with air passing through stainless steel fabricated ducts forming a false ceiling within the working chamber.
Air is equally distributed due to the furnace aerodynamic shape and passes through the charge at high velocity for heating by forced convection.
Speed of circulating fans will be controlled by AC motor drivers (frequency controls) depending on the furnace temperature.
Rotors and shaft of fans would be made from 310 grade stainless steel.
SCOPE OF SUPPLY
• Refractory materials, rockwool insulation and ceramic fibre insulation for furnace and door.
• Circulating fan assemblies, “V” belt and drive pulleys and electric motors.
• Burners, motorised valves, gas ratio valves, regulators, pressure switches, air fan, solenoids valves, shut off valves, flame relays, ignition transformers.
• Door gear mechanicals, pneumaticals cylinders, pressure gauge, valves, etc.
• Thermocouples
• Electrical control panel with control instrumentation motor starters, relays, etc.
• Steel fabrication and machined steel components including furnace casing and structural steel, packs and shims, motor brackets, furnace load supports and rails, door, door structure, brackets, door frame and balance weight, exhaust duct, stainless steel lining.
COOLING CHAMBER
SPECIFICATION FOR COOLING CHAMBER
NOMINAL CAPACITY 17 Tons
INSIDE LENGTH 7800 mm
WIDTH OF DOOR OPENING 2200 mm
OVERALL WIDTH 4500 mm
OVERALL LENGHT 7000 mm
COOLING FANS (3x 60.000 m3/h)
MOTOR SIZE Option_1 30 KW
TIME TO COOL CHARGE 3,5 hours
INITIAL COOLING RATE 300 oC/h
ELECTRIC SUPPLY 380 V 3 ph 50 hz
DESCRIPTIONS
Cooler Construction
The cooling chamber would be fabricated from 4 mm thick steel plate, reinforced with steel sections, to form a rigid floor mounted unit.
The load would be supported on heavy duty rolled stell beams, arranged longitudinally on vertically mounted tubular stools, in a similar configuration to the furnace hearth.
Access would be via a roller shutter door.
Cooling System
The cooling fans would be pedestal mounted in the chamber side walls, to draw air horizantally through the load at high velocity, to promote rapid and uniform cooling of the billets.
The fan assemblies would incorporate “vee” belt drives, fabricated support stools, guards, motors, plug housing, bearings, heavy duty shafts and backward inclined impellors.
Air would be drawn into the fans through duct sections with adjustable louvers, strategically positioned to facilitate an even air flow across the load and associated fan inlet cones sited in the plenum section of the chamber.
Control Panel
The control panel will comprise of a floor mounting panel which will incorporate the motor contactors, push buttons lamps and terminal rail for field wiring.
System Design Parameters
The cooling system would be designed to cool a load of 203 dia billets weighing 30000 kgs from 580 oC to 100 oC in 3,5 hours.
The initial cooling rate which is critical for optimum metallurgical properties would be a minumum of 300oC/hour.
The large volume of air circulating would guarantee fast and uniform cooling.
SCOPE OF SUPPLY
• Fans with electrical motors
• Fabricated steel casing and load supports
• Roller shutter door
CHARGING CAR FOR HOMOGENISING FURNACE
SPECIFICATION FOR CHARGING CAR
MAXIMUM LOAD 17 Tons
MAXIMUM LENGTH OF CHARGE 7400 mm
MAXIMUM WIDTH OF CHARGE 1800 mm
FORK EXTENSION 7600 mm
WIDTH OF LOAD CARRIAGE PLATFORM 1400 mm
LOAD CARRIAGE LIFT 70 mm
NUMBER OF ROAD WHEELS 6
CENTRES OF ROAD WHEELS 2500 mm
DIAMETER OF ROAD WHEELS 500 mm
OVERALL LENGTH 9000 mm
TRAVERSE DRIVE MOTOR Hydraulic
TRAVERSE DRIVE SPEED 10 m/min
LOAD CARRIAGE LIFT Hydraulic
LOAD CARRIAGE DRIVE MOTOR Hydraulic
LOAD CARRIAGE LIFT SPEED 10 seconds
LOAD CARRIAGE DRIVE SPEED 6 m/min
DESCRIPTIONS
General
The charging machine would be fabricated from rolled steel sections, suitably braced and stiffened to form a rigid structure. At the rear of the unit an operators platform would be incorporated, complete with control console and heat resisting screen.
Traversing would be achieved by the utilisation of hydraulically operated gearboxes, driven bogie type wheels, supported from the base frame by shaft and bearing assemblies.
The load carriage would be supported from wheel assemblies and driven by a rack pinion mechanism, operating in conjuction with a helical gearbox and associated hydraulic motor.
Traverse Functions
To enable loads to be transferred to and from furnace, cooler and load stations, the following motions can be carried out.
• Traverse of complete machine up and down length of shop on rails tracks.
• Forward drive of load carriage into furnace, cooler or load station.
• Raising or lowering carriage platform to pick up or put down load.
Main Frame and Traverse Drive Mechanism
The main frame will be fabricated from rolled steel sections suitably braced to form a strong and rigid structure.
Twin rails tracks would be located on top of the main frame to support and guide the load carriage assembly.
The road wheels arranged onaxles and mounted to main frame by means of bearing units. The wheels on one side of the machine would be coupled by means of a line shaft for synchronous movement when travelling. The line shaft would comprise a gear box and hydraulic motor.
Load Carriage Unit and Lift Mechanism
The lower section would incorporate wheel assemblies which run on tracks located on the machine and furnace/loading stations when extended. The wheels have integral ball bearings and run on axles located in the load carriage frame.
The upper sections or load platform would be connected to the load carriage frame by linkages enabling the platform to be raised or lowered by means of hydraulic cylinders.
The load carriage would be driven by means of a rack running the full length of the under carriage. This rack would then be engaged by chain wheel at one end of the main frame.
Chain drive would be by means of a hydraulic motor via geared unit supplied with bearings and drive shaft.
Hydraulic Power Unit
The hydraulic power unit serving the drives would be located at the rear of the machine with solid pipe and flexible hose connections as appropriate to connect to the cylinders and drive motors.
,Electrical Controls
Electrical control equipment would be housed in a control desk located at the rear of the machine.
The control equipment would include an isolator, relays, lamps, etc together with motor starter for hydraulic pump.
SCOPE OF SUPPLY
• Fabricated steel frame, wheel housing, platforms, heat shield, carriage forks, locating bolt strikers, brackets.
• Machined wheels, shafts and levers.
• Gear units, couplings, bearings, chain and chain wheels.
• Hydraulic power unit.
• Electrical control desk
• Mechanical assembly of machine.
