... dia.)Rotary Speed(rpm)TFJ737G737High abrasive formations such as limestone, dolomite,chert and hard sandstone,etc.Large radius conical ... hard with high compressive strength and abrasiveness,such as limestone,dolomite and sandstone,etc.Conical compacts in inner row ... .10200~40THJ737G737Hard formation with high abrasiveness,such as hard limestone,dolomite,hard sandstone and chert,etc.Large radius conical ...