Abstract: A coated abrasive article comprises a backing having first and second opposed major surfaces. A make layer is bonded to the first major surface. Agglomerate grinding aid particles are directly bonded to the make layer. At least a portion of the agglomerate grinding aid particles comprise grinding aid particles retained in a binder, and are arranged according to an open predetermined pattern. Abrasive particles are directly bonded to the make layer in spaces between the agglomerate grinding aid particles. A size layer is directly bonded to the make layer, agglomerate grinding aid particles, and abrasive particles. A method of making a coated abrasive article, in which the agglomerate grinding aid particles are deposited onto a curable make layer precursor prior to depositing abrasive particles onto the curable make layer precursor in spaces between the agglomerate grinding aid particles is also disclosed.

Abstract: A pipeline retard, support, and protection method wherein a fast-setting, expandable, organic spray foam is sprayed at spaced locations in a trench to create support pads and retards in the trench. The foam constituents are mixed in a spray apparatus and directed as a spray foam into the trench where it rapidly expands and stiffens into a layer of foam. Rapid expansion and corresponding rapid stiffening is believed to cause the cells in each layer of the foam structure to be elongated essentially normal to the plane of the layer. This cellular configuration in each layer imparts vertical strength and limited lateral flexibility to the structure. A plurality of layers of foam are sequentially formed in the trench to fabricate the desired structure. The placement of each layer is sequenced so as to permit a membrane to form on the surface of each layer for improved strength and inhibition of water penetration.

Abstract: A pipeline retard, support and protection method wherein a fast-setting expandable foam is placed in a trench at spaced locations below and around a pipeline to create spaced retards and support pads in situ. Each retard and/or support pad is created in the absence of forms or other foam molding means for the expanding foam. The retards may be keyed to the trench walls and base for securement. The system is also adaptable to encapsulating a portion of the pipeline which transverses a roadbed.