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SECO/WARWICK

manufactures custom engineered aluminium log and billet homogenizing furnaces for most process applications. Equipment designs include batch types (both car and tray designs), traveling styles and continuous styles, complete with material handling systems and load cooling equipment. Unique reversing airflow designs and temperature control systems produce fast heating rates with

Continuous Patented Baffle Design

Continuous log homogenizers are used by plants having higher production levels and a narrow range of product to be homogenized. High velocity jet heating is used to heat each log to homogenizing temperature very quickly. This design uses charging equipment to load one log at a time into a walking beam SECO/WARWICK holds the patent on the adjustable airflow baffle. These movable baffles greatly increase furnace performance, especially when less than the maximum size loads are being homogenized. The baffles are adjustable according to the height of the load to effectively limit or block the open space that exists above the load. The blocking of the airstream forces the recirculated air to pass through the spacing between each layer of logs or billets rather than taking the path of least resistance over the top of the load. Thus, an increased airstream velocity through the load is created, providing faster heat transfer and close temperature uniformity throughout the entire load. furnace or a similar semi-continuous type furnace. The logs are advanced through the heating and soaking chambers on specially designed hearth saddles to reduce friction and improve straightness. At the discharge end, each log passes through a specially designed quench chamber and then onto the accumulator table. Automatic controls adjust improved load temperature uniformity. One side of each movable baffle is fixed to the stationary horizontal baffle by an engineered hinge arrangement. The other side is connected to roof mounted electric operators. The operators include position transducers and limit switches to provide location information to a PLC. Benefits of the adjustable baffle include:

Batch

increased airflow velocityPreventing short circuiting of the airflow when less than the maximum size load is homogenizedPreventing overheating of the top layerLower energy requirements since faster heat-up rates are achievedIncreased uniformity since the airflow is channeled more evenly across all load surfaces With the batch type design, typically an electrically driven insulated car is used to move a load into and out of the furnace. Often, a double-ended furnace (door at each end) is used with two cars so turnaround time is reduced, thus maximizing production.The alternative to the car bottom design movements, timing and cycle parameters according to log diameter. SECO/WARWICK can also provide the auxiliary equipment for a complete system. for the batch type units is the tray design. With this design, the load tray rests on a series of support piers within the furnace. A charge machine/transfer car is used for charging/discharging of the tray and transferring the tray from the furnace to a cooling station or to a load/unload

Airflow Patterns

The patented reversing airflow design with upstream/downstream temperature control using an axial flow fan wheel reverses rotation on a timed basis, which, in turn, reverses the direction of the horizontal airflow through the load. The air stream temperature is monitored and controlled on each side of the load. A thermal head station.A third type of batch unit is the traveling furnace. This furnace uses a pair of fixed load bases to support the load. When the cycle is completed on base No. 1, the furnace moves into position over the second load base and immediately begins heating a new load. The is used during the early stages of the cycle for fast, efficient heating. This design increases both the heating rate and temperature uniformity of the load compared with one-way airflow, resulting in better efficiency, lower fuel cost, and improved metallurgical results. previous load is allowed to cool, then is unloaded and replaced with a new load. This can all be accomplished before the next homogenizing cycle is completed. A traveling furnace provides savings in floor because the two load bases require significantly less floor space compared with a double-ended stationery furnace

Cooling Systems

Cooling after homogenization can add significant value to the logs or billets. Production requirements are requiring faster, more uniform cooling of the logs or billets. Evidence increasingly shows that the resulting grain structure and workability properties of the billets are a result of the cooling medium to used after homogenization. While fast cooling is desirable, it must also be uniform throughout the load space or significant bowing of the logs could occur. For batch type loads using a car or tray, SECO/WARWICK offers a variety of load cooler designs such as one-way airflow, reversing airflow, air/mist arrangements, etc., depending on the level of performance required.These chambers are designed to cool the load uniformly to your specifications. Loads are usually plunge cooled at rates that can approach 700°F/hr in the initial stages of the cycle. The cooling rate can also be controlled using variable speed cooling fans. Shorter heat up rates due to with two load cars.
Solid lines show maximum andminimum temperature all duringcycle with S/W Patented HeatingSystem. Temperature spread was27°F at 4 hoursDash lines show maximum and minimum temperaturesfor the same furnace and load but withone-way flow. Spread 30°F at 5 hours. 120010008006004002000Time in hours4 hrs.5 hrs. °F Batch style furnace with car Continuous operating system Traveling furnace Load cooler Movable baffle (lowered position) Baffle assemblies Comparison of one-way nad reversing airflow airflow

Aluminium Homogenizing Furnaces - 16223 www.secowarwick.com.pl www.secowarwick.com.pl