变电站绝缘子RTV涂料自动喷涂系统设计及试验研究

发布时间：2018-11-19 07:19

【摘要】：RTV是一种防止污闪涂料,被普遍应用于电力系统各高压变电站电气设备绝缘子上防止污闪。目前,对绝缘子喷涂RTV主要通过工人手工喷(刷)涂方式实现,易造成浪费涂料、污染环境、涂层质量无法保证,以及人身安全隐患等问题,因此,有必要探索和研制一种绝缘子RTV涂料自动喷涂清洗系统,实现对绝缘子进行RTV涂料的自动喷涂及喷涂前的清洗。首先,对喷嘴外流场进行仿真分析,研究喷涂参数对喷涂质量的影响。由于RTV涂料属于油漆类型,其变形速率与切应力不符合线性关系,因此本文仿真的流体设为非牛顿流体。基于相关流体力学的基本理论,利用流体力学仿真软件Fluent对不可压缩的非定常流动流体进行了气液两相流喷嘴外流场的仿真研究。选择Fluent软件中近壁面模型法对壁面进行处理,研究了喷枪工作运行参数(如工作压力、RTV液体流量)对喷涂外流场的影响,并对喷涂过程进行了物理实验测试,通过以上研究分析和实验对比,发现仿真效果和实际试验效果基本相符,为设置RTV涂料自动喷涂系统参数以及如何进一步提高喷涂质量等奠定了理论基础。然后,基于RTV涂料(半)自动喷涂的功能需要,结合绝缘子的伞裙结构特点,完成了新喷涂装置的原理方案设计、详细结构设计、控制系统设计、非标零部件加工制造、控制电路设计与制备等。(1)本装置采用开口转盘结构,绝缘子可以通过转盘缺口直接进入装置中心,不需要拆卸绝缘子,可以实现对电站已安装好的绝缘子伞裙进行喷涂及清洗。(2)为了适应变电站绝缘子伞裙的形状和大小的变化,在喷涂装置上添加了相应的调节装置,用于调节喷涂水平距离和垂直高度,实现对一定尺寸范围内任意直径的绝缘子伞裙的可喷涂性。(3)为了保障系统的持续可用、防止喷枪堵塞、喷涂前对绝缘子表面的净化处理等,通过切换RTV涂料喷涂管路和清洗(如水或专用清洗剂)管路,可以实现清洗和喷涂的功能集成。(4)整个系统通过研制的控制电路进行(半)自动控制,保障喷涂过程的自动化以及喷涂质量稳定性等。最后,对全套系统进行总装、联调和样机试验。基于喷嘴外流场仿真分析结果,编写设置了相关喷涂清洗工艺及参数,对整套系统总装后进行了联调,在联调通过后进行了样机的实际喷涂试验。与人工手动喷涂效果对比后,发现本套样机喷涂的涂层具有均匀性良好、表面光泽、无(少)积瘤等优点,并且室温硫化后绝缘子上表面的涂层厚度均达到电力行业标准规定的0.4-0.6mm范围要求。
[Abstract]:RTV is a kind of anti-pollution flashover coating, which is widely used to prevent pollution flashover on insulators of electrical equipment in various high voltage substations of power system. At present, RTV spray on insulator is mainly realized by manual spraying (brush), which can easily lead to waste paint, pollute the environment, the quality of coating can not be guaranteed, and the hidden danger of personal safety and so on. It is necessary to explore and develop an automatic cleaning system for insulator RTV coating, which can realize the automatic spraying of insulator with RTV coating and the cleaning before spraying. Firstly, the effect of spray parameters on spray quality is studied by simulation and analysis of nozzle flow field. Because RTV coating belongs to paint type, its deformation rate and shear stress do not accord with the linear relationship, so the fluid simulated in this paper is set as non-Newtonian fluid. Based on the basic theory of correlated fluid mechanics, the flow field of an incompressible unsteady flow nozzle was simulated by using the fluid dynamics simulation software Fluent. The near wall model method in Fluent software is selected to deal with the wall surface. The influence of the operating parameters (such as working pressure, RTV liquid flow) on the spray flow field is studied, and the spray process is tested by physical experiments. Through the above research and comparison, it is found that the simulation effect is basically consistent with the actual experimental effect, which lays a theoretical foundation for setting the parameters of RTV coating automatic spraying system and how to further improve the spraying quality. Then, based on the functional requirement of RTV coating (semi-automatic spraying), combined with the structural characteristics of the insulator's umbrella skirt, the principle scheme design, detailed structure design, control system design, non-standard parts processing and manufacture of the new spraying device are completed. Control circuit design and fabrication etc. (1) the device adopts an open disc structure, the insulator can enter the center of the device directly through the gap of the rotary disc, and the insulator does not need to be removed. It is possible to spray and clean the insulator umbrella skirt installed in power station. (2) in order to adapt to the change of the shape and size of the insulator umbrella skirt in substation, a corresponding adjusting device is added to the spraying device. It is used to adjust the horizontal distance and vertical height of spraying, to realize the sprayability of the insulator umbrella skirt with any diameter in a certain size range. (3) in order to ensure the continuous use of the system and prevent the spray gun from clogging, Cleaning the insulator surface before spraying, by switching the RTV coating spraying pipe and cleaning (such as water or special cleaning agent) pipeline, It can realize the function integration of cleaning and spraying. (4) the whole system can be controlled (semi-automatically) by the developed control circuit to ensure the automation of spraying process and the stability of spraying quality. Finally, the complete system assembly, union and prototype test. Based on the simulation and analysis results of nozzle flow field, the related spray cleaning process and parameters were programmed and adjusted after the assembly of the whole system. The actual spraying test of the prototype was carried out after the joint adjustment. Compared with manual spraying, it is found that the coating has the advantages of good uniformity, glossy surface, no (less) nodule and so on. The coating thickness of the insulator surface after room temperature vulcanization is up to the 0.4-0.6mm range stipulated by the power industry standard.
【学位授予单位】：华北电力大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ639;TM63

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