Blue Demon - Model SH 800 - Replaceable Blade
The Type SH-800 bit is primarily designed for drilling with extra-heavy weights. Such drilling equipment generally uses up to 3½' 88.9mm) or 4½' (114.3mm) drill pipe. In formations predominantly shale where hard stringers are encountered, the 55/8' (142.9mm) through 8¾' (222.2mm) Insert Blades are most successful. In softer formations where 3½' (88.9mm) or larger drill pipe is commonly used, Insert Blades through 12' (304.8mm) are available and Rock Cutter Blades may be obtained in sizes through 16' (406.4mm).