The hydraulic baler is mainly suitable for steel mills, crop straws, recycling and processing industries and non-ferrous and ferrous metal smelting industries. The hydraulic baler can extrude various metal scraps (steel shavings, scrap steel, scrap aluminum, scrap copper, scrap stainless steel, and scrapped automobile scrap, etc.) into qualified furnace materials of various shapes such as cuboid, octagon, and cylinder, which can be reduced Transportation and smelting costs can increase the furnace speed.