dry type vs wet type fish feed extruder : 4 main differences

what is dry type fish feed extruder?

there are two types of fish feed machines for making floating aquatic feed, one is dry type fish feed extruder, the other is wet type fish feed extruder. The dry type fish feed extruder is mainly used for the production of aquatic feed, such as making fish feed pellets, tilapia feed, catfish feed pellets, shrimp feed, crab feed, turtle feed, goldfish feed pellets, etc. The finished pellet feed is extruded at high temperature through the heating plate in the dry type fish feed machine.

Therefore, the finished granules can float on the water for about 24 hours due to being puffed. Finished particle sizes can be 0.9mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm, 5.5mm, 6mm etc up to a larger 15mm. dry type machine heating the material by electric heating plate, this dry type machnine extrudes the material from the holes of the die under the action of the screw extruder. When the pellets come out of the machine, the pressure and temperature drop sharply, and the water evaporates. The material is then expanded into particles with a porous structure. During this process, moisture ranges from 15% to 20%.

video of dry type fish feed extruder

working principle of dry type fish feed extruder

when extrusion operation, the material from the open end of the extrusion cavity input, by the screw transport to the entire extrusion cavity, and then the auxiliary extrusion part into a number of areas, in each area between the placement of a ring (pressure ring) as the flow and pressure control, the screw conveying action to promote the material flow through the ring gap between the pressure ring and the inside of the cavity, the mechanical energy generated by the rotational movement of the screw into heat The friction between the material and the parts of the dry type fish feed extruder machine and the internal friction of the material.

As the material is extruded through the die hole at the end of the puffing cavity, the dough-like material is processed into a certain shape, and due to the huge propulsion of the screw in the puffing cavity of the dry type fish feed machine, a huge pressure is generated. Forming in the material, when these materials are extruded from the die hole, a large amount of water in the material evaporates instantly, which greatly reduces the moisture content of the material.

what is wet type fish feed extruder?

Wet type fish feed extruder machine is also widely used to produce raw materials into high-grade floating aquatic feed pellets, which is suitable for fish, catfish, shrimp, crab, cat, dog and other pets. The raw materials used by the wet type fish feed machine are wheat, soybean, cake and other scraps, etc., and the puffed particles produced by the wet type fish feed extruder machine can float on the water surface for more than 24 hours without dissolving.

Wet type feed extruder machine are mainly used in large and medium-sized feed processing plants and farms. it works with the steam boiler, the boiler continuously can supply hot steam to the wet type fish feed machine extrusion part. The working principle of the wet type machine is similar to that of the dry type fish feed extruder machine. But the wet type requires adding water or steam in the wet type fish feed machine to increase the moisture to twenty percent, or more than thirty percent during processing. It raises the temperature of the material by steam.

video of wet type fish feed extruder

working principle of wet type fish feed extruder

the wet type fish feed machine consists of screw, barrel, template, fixture, etc. The screw and barrel are combined in sections, and the compression degree can be adjusted according to the type and requirements of the extruded feed, and the expansion degree of the extruded feed can be changed. When the raw material enters the filling device, no additional heating is required and the screw is pressurized at high pressure and high temperature to fully cook and sterilize the raw material.

During the high temperature curing process, the starch and fibers in the raw material expand. The material is then molded into pellets through the molding die under pressure-sealed conditions. Finally, the high pressure generated by the regular rotation of the screw is cut by the regular high-speed rotation of the front cutter, and the finished product is shrunk into an average small puffed ball at room temperature and pressure.

dry type fish feed machine

wet type fish feed machine

4 main differences between dry type and wet type

sepecifications of wet type fish feed extruder

specifications of dry type fish feed extruder