Latest from Issues and Ideas

Warut Sintapanon | Dreamstime
Bobby17 | Dreamstime
Nordroden | Dreamstime
Nightman1965 | Dreamstime
Anthony Baggett | Dreamstime
Pop Nukoonrat | Dreamstime

Fluid-Bed Sand Cooler/Classifier

Jan. 16, 2009
A maintenance-friendly design allows quick exchange of bundles, even on a partial down shift.

The Vulcan Engineering Co. cooler/classifier offers a maintenance-friendly design that allows quick exchange of bundles, even on a partial down shift. Optional inlet vibratory screens are available to add one more level of screening for removal of unwanted debris from the sand stream. The forced air cooling system also provides an excellent method for removing unwanted fines from the sand stream. (Excess fines will absorb binder and directly reduce mold strength.)

The non-linear path of the sand and the multiple-stage weir layout ensures efficient heat transfer from the sand to the water through heavy-duty finned tubes. This design provides a maximum of sand cooling in a minimum of floor space, lowmaintenance operation and high reliability.

The plenum-plate fluidization method maintains a constantly flowing bed of sand, thus providing ample retention time for cooling as well as protecting the finned tubes from the abrasive characteristics of the sand.

The non-linear path of the sand ensures efficient heat transfer. The plenum-plate fluidization provides ample retention for cooling, as well as protecting the finned tubes from the abrasive characteristics of the sand.

Features

• Designed to fluidize, cool, and transport various types of foundry sand;
• Interchangeable heat exchanger cooling element assemblies designed for easy removal and replacement, if required;
• Multiple stage, centrifugal type, direct-drive fluidization blower complete with NEMA T-frame motor and inlet silencer. This type blower requires less maintenance and is more tolerant of contaminants than positive-displacement blowers used by competitive products;
• Fluidization air ductwork and air flow adjustment valves to allow blower to be positioned within a reasonable distance of the sand cooler;
• Thermometers for sensing sand and water inlet and outlet temperatures; and,
• Fluidization and exhaust air pressure switches. Advantages
• Finned tube heat-transfer elements greatly increase the heat-transfer surface area, thus reducing the size of the fluidized bed requiring less fluidization air, and consequently reduces power consumption;
• Larger tube diameter and wall thickness (1.5 in., schedule 40) greatly increases strength, and protect tubes from further sand abrasion;
• Thermal expansion of the cooling elements is accommodated by allowing entire cooling element to expand into the non-fluidized sand area inside the cooler;
• Finned tubes are assembled into cooling elements by welding at both ends. There are no “0” rings subject to damage from high sand-inlet temperatures. The gasket at each end of each cooling element is not exposed to actively fluidized hot sand;
• Easy-open inspection doors allow unobstructed view of sand cooler interior for initial adjustment and periodic inspection;
• Each cooling element has a dry removal weight of less than 2,000 lb, and is approximately 62 in. long. This allows for much easier and quicker removal and maintenance of the cooling elements, as compared to competitive designs; and
• Smaller overall footprint than competitive designs due to the unique cascading design.