gives the material that has been brought forward achance to fall out the apron opening.NOTE: When the material is spread too thin or thebowl is too low, the material will pack against thescraper cutting edge inside the bowl and will not eject.Loose Sand and GravelSand is a free-flowing material that tends to floatahead of the scraper cutting edges when being loaded.To obtain a heap scraper load when loading and to avoidbeing bogged down by the sand, use the technique calledpump loading. To pump load, enter the cut with theapron open about 3 feet and the scraper cutting edgeslowered into the sand. Continue through the cut untilthe engine(s) starts to lug down. Then lower the aproninto the sand that has piled up in front of the scrapercutting edges, and raise the bowl 2 or 3 inches at a time.Do not completely close the apron or drop the bowl sodeep that the engine stalls. This pump loadingtechnique will ordinarily allow the scraper to get a fullload.When spreading sand, always spread it as thin aspossible, and keep the scraper moving in the fill. A thinspread allows better compaction and makes it easier totravel over the fall.To obtain a full load when loading gravel, you mayhave to pump load as performed with sand. The apronmay be hard to close due to stones getting caughtbetween the apron and cutting edges. A technique usedto avoid the stones is to backup a few inches with theblade still in the ground while closing the apron. Thisshould force the stones out and allow the apron to closeall the way.Large ObjectsScrapers are not designed to dig or transport largeobjects; however, they may be used for this purposewhen more suitable equipment is not available.Approach the object with the apron and scraperbowl fully raised. When the object is too large to clearunderneath the tractor, bring the tractor past the objectuntil the drive wheels are a few inches beyond it. Pivotthe tractor sharply towards the object to allow the tractorto bypass the object, and bring the cutting edge intoposition for loading (fig. 10-43).When the tractor reaches its sharpest angle of theturn, bring the scraper cutting edges within a few inchesof the object. Lower the bowl, apply down pressure, andmove forward.When the cutting edge hooksunderneath the object, lift the bowl while inchingforward. When the object slips off the cutting edge,back up and try again. You may have to approach theobject from a different direction to get a grip to load theobject.To shove the object around, keep the ejector in thefull forward position. When the object is to be pickedup and carried, place the ejector in the normal fullbackposition. To close the apron completely after the objectFigure 10-43.-Scraper maneuver to load large object.10-23
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