绳拖网网口结构设计和装配工艺

本文主要阐述适用于我国东海和黄海渔场的双船两片式底层绳拖网网口结构设计，上、下纲和悬纲长度计算方法及其装配工艺。根据绳拖网的上纲和下纲的工况特点，上纲呈抛物线状；下纲呈悬链线状，分别依据其各自的曲线方程组求算。关于悬纲和上、下纲之间的装配工艺，是按我国底层拖网特点设计的。经生产实践，证实这些设计和装配都是合适的。

A DESIGN FOR THE STRUCTURE OF THE NET MOUTH OF ROPE TRAWL AND ITS RIGGING TECHNICS

This paper describes a design for the structure of the net mouth of the two-panelbottom rope trawl, the method calculating the lengths of the headline, footrope andhanging line, and the rigging technics. According to the different working conditions between the headline and footrope,the following formulas are adopted. The headline (assuming the parabolic form): y =a₀x²; s=integral from x₁ to x²(1+y'~3)~(1/2)dx The footrope (assuming the catenary form): y=a/2(e~(x/a)+e~(-x/a)); s=a/2(e~(x/a)-e~(-x/a)) Where y-rope length; x-horizontal distance; a,a_0-parameter; s-headline orfootrope length The rigging technology for the headline, footrope and hanging line was designedin accordance with the characteristics of China's bottom trawl. It has been proved thatthe design and rigging described above are useful.