Research On Scaling Method For Freshwater Fish

The freshwater fish production of our country is the highest in the world, however, its processing relatively lags behind, which has already restricted the development of freshwater aquaculture. Basis on broad and full understanding of technology and equipment to the scales of freshwater fish both home and abroad, we measured the bio-adhesion force between fish scale and its body, analyzed and experimentally verified its influence on scaling, studied continuous scaling method for freshwater fish, for the demand of mechanized processing of large freshwater fish, especially scaling link.Took common carp, grass carp, crucian and bream as objects, used TMS-PRO type texture analyzer to measure the bio-adhesion force between fish scale and its body, studied some factors' influence on fish scale's bio-adhesion force, such as fish scales' position,loading rate and length of dead and so on. The results show, the bio-adhesion forces of scales between different species of fish are significant different; For common carp, grass carp and bream, the bio-adhesion forces of different parts are significant different, for crucian, they are not significant; when the loading rate between 10-50mm/min, it has no significant influence on the bio-adhesion forces of fish scales; but time of death has a significant influence, showed that the fish is fresher, the bio-adhesion forces of fish scales will be bigger.Used a test bench made by ourselves, measured silver carp's friction angle both forward and reverse, studied the relative velocity and angle between fish and tool's influence on scaling effect of freshwater fish. The results show, both the relative velocity and angle between fish and tool has a significant influence on scaling, scaling effect is better when the relative velocity is lager; when the angle between tool and silver carp is 32°, scaling effect is the best, and crucian is 23°,bream is 28°. Then analyzed and verified bio-adhesion force per unit area of fish scale's influence on scaling, the result shows that scaling is more difficult when the force per unit area is larger.Took sliver carp, bream and common carp as test objects, made several scaling brushes that made by different sharps and materials, studied their effect of scaling, the result shows that the brush that mainly made by spring has the best scaling effect. Then studied some factors'influence on scaling ratio and body injury of freshwater fish, such as spring external diameter, brush rotating speed, brush diameter and so on. Afterwards, we determined the optimal combination of the key factors, which were spring external diameter 21mm, brush rotating speed 840r/min, brush diameter 90mm. This study can provide reference for the design of continuous shelling scales equipment for freshwater fish.