Aerovent Fans Increase Aluminum Extrusion Production By 25%
Remelt Technologies, Inc. specializes in aluminum processing equipment. Their customers include the largest aluminum manufacturers in the U.S. and Canada. Remelt provides engineering design services and equipment for aluminum melting furnaces, holding furnaces, homogenizing furnaces, burner and control systems, casting machines, casting molds, billet saws, etc. Remelt purchases Aerovent fans for use in a wide variety of applications in the manufacturing of aluminum metals.
Remelt contacted Aerovent representatives to assist in the design and selection of fans for an aluminum log cooling station. Aluminum logs ranging in diameter from 6” round to 13”round x 17’-0” long are stacked in a load approximately 17’-0” wide x 8’-10” high x 11’-0” deep. Each row of aluminum logs is spaced from the next row using custom fabricated 2” or 3” stainless steel spacers. The load of aluminum logs is approximately 160,000 lb. and is heated to 1080°F in a homogenizing furnace. The purpose of the cooling station is to cool the load from 1080°F to 500°F in one hour. This process is critical to achieving the proper metallurgical properties for subsequent extrusion.
There are many factors that affected the fan selections. The types of fans used for an aluminum log cooling station range from inexpensive commercial grade products like portable man-coolers or panel fans to very large and expensive centrifugal fans. Entering air temperatures can be -20°F to +98°F. The large volume of air required to cool the load is limited to the small open slotted area between the 2” or 3” spacers. The sizes and weights of the aluminum logs vary in each load so the requirements for air volume and pressure change. The fans had to be compact, lightweight, durable, high volume, and stable at varying pressures.
Six (6) Aerovent model 48W723VW-1160RPM-20HP were selected. The fans were provided with inlet bells, inlet guards, and custom mounting brackets for installation in Remelt’s portable log cooling station. The fan inlets on three of the fans were lengthened and staggered to reduce inlet airflow system affects. The portable cooling station incorporated a movable baffle system that retracted out of the way for positioning of the aluminum logs and extended over the loads during operation.
“The improvement to extrudability was substantial” according to the customer. There was a 25% increase in pressing speeds with no signs of diminishing surface quality. The billets could be run so fast that the press overheated at the end of the runs and speeds were limited to reduce stress on the machines. Remelt has received inquiries for two more cooling stations as a result.