我国组装式浮盘的发展与建议

Development and Suggestions in Modular Floating Deck of Covered Floating Roof Tank

内浮顶油罐的组装式浮盘,是将在工厂制成的标准模块式构件运至施工现场后,按照构件安装顺序从油罐人孔送入罐内,用螺栓或铆钉组装成形。其造价低,安装速度快,使用安全可靠,降耗效果好。近20年,我国组装式浮盘的使用量超过5000台,且绝大多数是铝浮盘,其结构基本定型在铝合金骨架、浮力元件为浮筒的范畴之内。对国内常用组装式浮盘的结构合理性进行了分析:浮盘周向刚度较小,轴向刚度较大,以保障其顺利通过阻卡而不发生"折盘";浮筒是浮盘的浮力元件,其分布越均匀越好,同时应使浮盘周边的浮力稍大;浮盘与油面间存在油气空间是保障内浮顶油罐和组装式浮盘安全运行的有利条件。密封装置是浮盘的关键构件,宜采用舌形密封。讨论了其他辅助构件如扩散管、盖板、支腿、通气窗、溢液管在设计、安装中应注意的问题。虽然组装式浮盘涉及的行业范围较窄,但其应用数量多,经济与社会效益大,而制造商的研发和生产能力不强,为此提出了组装式浮盘的发展建议。

Standard modular structures of covered floating roof tank are generally workshop manufactured before being transported to the installation site,and then they are launched in the oil tank through man-hole in order and assembled with bolts or rivets.Modular structure of covered floating roof tank is characterized by low cost,short setting time,safe and reliable with higher energy saving rate.In recent 20 years,more than 5.000 modular floating decks have been used in covered floating roof oil tanks,the most of which are made of aluminum floating decks,and their structures are formed in aluminum alloy frames and buoyancy components as pontoon.In this paper,the structure rationality of current modular floating deck in China is analyzed.It is concluded that smaller circumferential stiffness and larger axial stiffness can ensure the modular floating deck to successfully pass through the sticking and prevent being logged and broken.Pontoon is kind of floating component of deck,and the more uniform arrangement of it is neces-sary.And at the same time,circumferential buoyancy of the modular floating deck should get a little bit bigger.The space between the floating deck and oil surface can ensure safe operation of the covered floating roof oil tank.Because sealing device is a key component of floating deck,the tongue-shaped seal is better.Some design and installation problems in auxiliary compo-nents,such as diffuser pipe,cover board,outrigger,venting window and overflow pipe,are also discussed.Although the modular floating deck belongs to an narrow field in the industry,it has been widely applied with remarkable economic and social benefits.Considering lower capacity in development and production for industrial manufacturers,some suggestions in the future development of modular floating deck are proposed.