虾球麻麻
This paper introduces the classification of ball valve and ball valve of the advantages and disadvantages of various types, focusing on large-diameter ball valve types and applications, as well as my subject DN500 large diameter natural gas ball valve of the applicable valve type. Including how the selection, calculation. According to GB150-1998, "Design and Simulation valve", "ball valve design and selection", "Valve Design Manual", "Practical Design Manual Valves", "Mechanical Design Manual" in the contents and formula, I chose make two side-mounted ball valve. This article has done a series of calculations on the ball. Describes the calculation of body thickness, two-way ball valve stem seal fixed torque and strength checking, double-seat two-way ball valve seal sealing surface of the fixed and the calculation of total force than the pressure on the ball of the valve seat ring Calculation of friction torque, the inlet valve seat ring on the ball of the friction torque terms, the import side of the ball valve seat ring friction torque terms, the export side of the ball valve seat seal the calculation of the friction torque, valve seat seal circle on the sphere of the friction torque, bearing friction torque calculation of thrust pad friction torque, friction torque and valve packing and O-ring and the friction between the valve stem, two-way ball valve stem seals switch to a fixed moment, stem strength calculation
是的。 国外也进行学术打假。
随着社会的高速发展和全球化的加速推进,各国的学术研究也在不断壮大和深入。中国的学术研究也不例外,各个领域的论文层出不穷,尤其是在一些科技领域,中国的研究成果已经
可以。在写毕业论文的时候要,需要写国内外的研究现状,研究现状可以参考文献当中的资料,也可以引用部分的资料,引用的内容是不算重复的,当然引用的不能太多,不能成段成
国内外研究现状的写法: 在撰写之前,要先把从网络上和图书馆收集和阅读过的与所写毕业论文选题有关的专著和论文中的主要观点归类整理,找出课题的研究开始、发展和现在研
毕业论文国内外研究现状在写之前、或者说是查找相关文献之前,需要明确以下问题: (1)研究所属的领域或者其他领域,这个问题已经知道多少。 (2)已完成的研究有哪些