Study On The Pagrosomus Major Grading Equipment For Sea Cage

This paper describes the grading technology and the application in fishery. Several different grading equipment are introduced .On the basis of Pagrosomus major's biology and behavior characteristic ,a Pagrosomus major grading equipment fitted for deep sea cage was designed and manufactured.In present, the manufacture of deep sea anti-storm cage comes into being industry .But the accessories and technology should be improved .Since the cage became larger, the bait can't be cast equally .At the same time ,there are biology distinctions between individuals ,so the fish in cage grow differently .They have differert sizes and constitutions .This will not only affect the growth of fish but also reduce the price of finished fish product and increase the labour of workers.So during the production of the deep see cage mariculture,the classifacation of fish should be done on time .On the other hand,the fish must be sorted according to the requst of the client when the fish are sold.This paper studied the theory of the sorting grid .The grading equipment which can divide fish into different standard was designed and manufactured to reduce the damage and death of the fish .This will increase the profit of the cage mariculture, decrease the labor intensity and improve the efficiency of the work.The sorting grid was usually used to divide the by-catch in foreign countries for trawl fishery and purse net fishery. The application of the sorting grid in fishery and cage mariculture was just studied in our country. The grading equipment refered in this paper are rigidity .They are used for Pagrosomus major whose weight are 500g and the grid bar space is 33mm.The average grading rate for small Pagrosomus major is 88.45% and the escape rate for big Pagrosomus major is lower than 10% in the large cage which is 30m in perimeter .All Pagrosomus major were scatheless aftergrading.The feeding behavior of Pagrosomus major is normally.