Secondary molding and manufacturing method for raw coal sample standard test piece of soft and easily crushed coal body

The invention discloses a secondary molding and manufacturing method for a raw coal sample standard test piece of a soft and easily crushed coal body. The method comprises the following steps: selecting a coal body geological unit which is slightly influenced by mining, and sawing a cuboid coal briquette; sleeving the coal briquette by using an iron sheet square frame, and pouring polyurethane in a gap between the iron sheet square frame and the coal briquette; taking down the coal body from the coal seam, conveying the coal body to the ground, and performing wax sealing on the coal body to be conveyed to a specified site; removing the wax seal, sawing a circle along the polyurethane layer, and removing the polyurethane between the coal briquette and the iron sheet square frame; manufacturing the coal briquette into a cuboid test piece, grinding the cuboid test piece on a double-end-surface stone mill, and sawing off four corners of the cuboid test piece, so that the test piece is cylindrical; and putting the test piece into a cylindrical grinding tool, and supplementing the test piece into a standard coal sample test piece by using silicone acidic glass cement. The method disclosed by the invention has the beneficial effect that the raw coal test piece which can replace a coal briquette test piece can be manufactured.