A large amount of tools with abrasives on a backing material are turned into endless loop belts so that a bond location, called a seal, becomes necessary.
Great demands are placed on the tear strength of the seal area, especially at high chip removal rates. Synthetic resin adhesives and improved adhesive technologies permit large chip removal volumes without the risk of a premature belt tearing at the seal.
The abrasive belt ends are bevelled so that the seal runs diagonally to the grinding direction. In this way, the engagement of the belt in the seal area becomes practically hitchless.
The Abrasive Belt System
Abrasive belts can be constructed single or multiple-layered (Fig. 3-25). Multilayer coating leads to a much higher service life. Examples of this are the hollow ball abrasive belt [WAGN84], in which the grits are bonded in the shell of hollow balls made of vitrified or synthetic resin binding agents, and the compacted grit abrasive belt [BUCH89], in which up to 200 abrasive grits are packed together in one compacted grit.
The big advantage of the hollow ball abrasive belt is that the bearing percentage across most of the belt’s profile height remains constant. In this way, until the end of the belt’s service life, all of the abrasive grit material is engaged aside from a minimal residue remaining at the hollow ball base. At equal grit sizes and about three times the grit amount, the service life of hollow ball abrasive belts is up to 1000 % higher than conventional belts [STAR87].
Hollow ball abrasive belts are applicable first and foremost for belt grinding with support plates. In the case of peripheral belt grinding with contact rolls, strain is relatively high. For this, compacted grit abrasive belts are better suited. The latter also maintains nearly constant surface quality during the belt’s entire service life at up to a 200 % higher lifespan than conventional belts [BECK93].
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Multi Laver (hollow corundum)