Over the years there have been three different processes used to Crush (recycle / reclaim) Submerged Arc Welding (SAW) Flux Slag;
- Hammer Mills
- Rotary Cage Mill Pulverizer
- Fused S.A.W. Flux / Slag Crushing Unit
1) “HAMMER MILLS”
Typical Applications; Alum cake, Animal tankage, Barley shorts, Bran, Coal, Cocoa shells, Dried milk, Fish scrap, Gelatine, Gypsum, Limestone, Meat scraps, Oats, Salt cake, Shelled corn, Soya bean expeller cake, Steam bone.
Hammer mills were the most popular means of crushing SAW slag, however with today’s technology the hammer mill is no longer being used in the United States or Canada.
2) “ROTARY CAGE MILLS or PULVERIZER”
Typical Applications; Range from Asbestos Ore, to Zinc Skimmings. Typically they are mostly used in the fertilizer industry.
Rotary cage mill pulverizers have come into favor do to their being readily available and ease of use. However do to their intended purpose of "pulverizing", or turning the slag into powder (flour) the addition of new (virgin) flux is almost always required, this addition of new can be as high as 50%.
3) “FUSED S.A.W. FLUX / SLAG CRUSHING UNIT”
Typical Applications; Submerged Arc Welding Flux Slag Crushing (only).
Pros and Cons
||Slag Crushing Unit|
|No granular size control
||No granular size control
||Granular size control|
|Low production output
||Low production output
||High production output|
|No product inspection points
||No product inspection points
||Product inspection points|
|Easily trained operators
||Easily trained operators
||Skilled operators required|
The S.A.W. Flux slag Crushing equipment used at Harbert's Products, Inc., and Allied Flux Reclaiming, Ltd. was designed and built by Allied Manufacturing, Ltd. a Division of Allied Flux Reclaiming, Ltd. In fact Allied Manufacturing has sold three (3) Slag Crushing Units however only one (1) remains in use today and that unit is located at Harbert’s Products facility in Greencastle, PA. One of the two units was sold to a steel distribution company in Mississauga, Ontario, Canada in 1982 and the second to a slag crushing company in Cartersville, GA in 1988, do to lack of maintenance these two companies now use a Cage Mill Pulverizer as it is readily available and minimal skill is required to service it.
The “Fused S.A.W. Flux / Slag Crushing Unit” has been modified several times since 1958 when Alfred Beck first invented the process and equipment used, the last being 2004 this time it was modified by his sons Albert and Donald Beck. This new design has a waste stream of 6% to 10% (8% average).
The Fused S.A.W. Flux / Slag Crushing Units being used at Harbert's has waste stream of 6% to 16% (14% average), this difference is do to the type and size of the crushed flux.