Top Heated Galvanizer
The ruggedly constructed QED Top Heated Galvanizer provides our customers with reliable performance at very reasonable cost. The molten zinc is contained in a ceramic lined bath designed for a long trouble free life of over 25 years. Special low velocity burners fire into a combustion chamber that is sealed into the zinc surface. Exhaust gasses from the combustion hood can be ducted through a dryer to effectively recycle combustion heat. QED designs Top Heated Galvanizers to operate with LPG, natural gas, oil or dual fuels. This rugged equipment is easy to operate and requires little maintenance.
Features
• Low maintenance
• Lower capital costs
• Proven reliable design
• High combustion turn-down
• Multiple Fuels (Oil or Gas)
Furnace & Combustion Hood Assembly
The galvanizer shell is solidly constructed of rolled steel plate and structural steel sections.
The bath is heated by burners firing into a combustion hood that is sealed into the zinc surface. The combustion hood is mounted above the zinc and to the side of the wire field allowing easy access for operations. Special low velocity burners and a designed heat-transfer rate permit maximum production and minimum zinc oxide formation. The hood is lined with fiber insulation and light castable refractory providing better thermal efficiency and a low cold face temperature. The hood is supported by the base end walls and is designed to be lifted to allow maintenance of the zinc surface.
Refractory Design
The refractory lining is multiple layers of the latest generation of refractory materials. The hot-face lining is made of 9” (229mm) thick, high strength, high alumina content tiles. The interlocked tiles are fully bonded to provide an impervious container for the liquid metal. A special “freeze plane” design is employed to guaranty zinc containment, even in the unlikely event of a hot-face lining crack. A layer of back-up and a layer of insulating refractory ensure additional bath integrity and low heat loss.
QED provides the installation of the refractory as part of the equipment price.
Combustion Equipment
A state of the art panel with Siemens PLC hardware and our user friendly program provide advanced control functionality. Gas fired systems use special flat flame burners while our oil fired furnaces are end fired with special low velocity burners. Both systems utilize top quality Kromschroder and Hauck combustion components.
Flat Flame Burners
The burners are a special “nozzle mix” flat flame design with independent air and gas piping. Each burner is equipped with the following components; manual gas cock, automatic safety shut-off gas valves, gas metering orifice, gas flow adjusting valve, automatic air shut-off valve and pressure gauge. In addition the burners are designed for push button starting with ignition transformers and spark ignitors.
Flame and Gas Safety
A flame detection probe on each of the burners sends a signal to independent electronic burner control modules that are located in the main control panel. In the event of a flame failure the burner control unit, coupled with control panel logic, will close the burner’s gas and air valves and sound an alarm. An over-temperature thermocouple is located in the zinc that feeds a signal to an independent High-Limit Controller. This controller will automatically shut-off the main gas to the furnace and sound an alarm if an over-temperature condition exists. A low zinc temperature alarm is incorporated into the zone temperature logic to warn if zinc temperature has dropped to an unacceptable level. In addition the following combustion equipment is supplied: Main gas cock, Inlet gas filter, Main gas regulator, Low gas pressure switch, High gas pressure switch and Low air pressure switch.
Ancillary Equipment
A roll assembly is provided at the entry end of the furnace. The rolls are fabricated of hardened steel with “U” grooves. Each roll is mounted on an individual bearing and the assembly has a common adjustable height shaft. The furnace is supplied with a hood raising system to permit easy cleaning of the oxide from the zinc surface. Also our thermocouples are protected from zinc attack by special sheaths.
Additional Features and Options
Ceramic Sinker Assembly
The QED ceramic sinker assembly is built to submerge multiple strands of wire under the liquid zinc surface of the galvanizing bath. The assembly is custom designed to suit the purchaser’s production requirements, wiping configuration and wire line layout.
Construction
The support and lifting assembly is solidly constructed of structural steel sections and heavy steel plate to provide exceptional strength and minimum vibration. The sinker block can be removed from the zinc by rotating a hand wheel that is keyed to the reduction gearbox input shaft. The gearbox output shaft is directly coupled to a cross shaft that forms the spine of the sinker block’s support and clamping assembly. The reduction gearbox is mounted to a solid base located on the working side of the galvanizer. A locking mechanism is provided to dampen vibration and prevent accidental position changes.
Sinker Block
The sinker block is fabricated of high strength wear resistant ceramic material that is designed to provide a long life under normal operating conditions. The block is cast as a single piece with clamping taper, neck and body designed to suit the application. The radiused surface of the sinker is constructed with individual wire grooves to maintain the position and spacing of the wires. Lubricating ports on the radiused surface allow for zinc penetration to the contact side of the wires.