Abstract: Apparatus for self-clearing of clogs developed between adjacent ends of upstream and downstream conveyors adapted to carry products thereon in the course of transfer of the products past a gap defined between the conveyors. The apparatus comprises a shield disposed between the adjacent ends of the conveyors and adapted to cover less than all of the gap between the conveyors and having a proximal side edge disposed adjacent the end of the downstream conveyor, thereby defining an opening for the discharge of debris from the products being transferred between the conveyors through the opening. The shield is mounted for selected degrees of covering relationship to the gap between the conveyors.

Abstract: A wood chip sampling apparatus which includes a chip collecting tray. The tray moves to a first location where it collects a sample of downwardly flowing wood chips and then to a second location where it discharges the chips into a chip sample bin for later analysis. The tray is pivoted about a horizontal axis and is weighted on one side of the pivot axis so that it automatically assumes a horizontal, chip receiving orientation after chip discharge. An abutment prevents the tray from pivotting and dumping collected chips in the first tray location, the tray automatically pivotting to dump the chips when in the second location. The collecting tray thus reciprocates along a horizontal path and pivots over a range of 90 degrees.

Abstract: High-yield pulp suitable for the production of corrugating medium is produced by cooking hardwood chips at a temperature 180.degree.-192.degree. with sodium carbonate solutions of a concentration 65 to 120 g/l as Na.sub.2 O, at a liquor to wood ratio of 1.2-2.5, and mechanically refining the cooked chips in a primary refining stage to a C. S. Freeness less than 480, and then refining the pulp in a secondary refining stage.