不停输带压更换高压球阀装置

Device for Replacing High Pressure Ball Valve Under Non-stop Gas Transmission

天然气长输管道在运行过程中,各类旁通和支管上的高压球阀容易出现阀体泄漏、阀门内漏、无法注脂保养等一系列问题,为了妥善解决这类问题,依据此类阀门一端可以泄压放空的特点,研制了一套从阀门一端进行轴向封堵、更换阀门的装置。该装置主要由封堵头、操作杆、高压密封仓、分瓣式横梁、连接螺杆、环形卡箍等部分组成。在高压密封仓的封闭状态下,通过分瓣式横梁和操作杆把穿过待更换阀门的封堵头推送到管道内的封堵位置,而后旋转操作杆使封堵头受到挤压膨胀,实现对管道的压力封堵,然后更换下有问题的阀门。该装置按照DN50球阀的尺寸进行设计并制作出实物后,在现场进行试验,成功地完成了带压更换阀门的工作。该装置优点在于不用停输干线,不用焊接动火,可以在线带压更换与干线相连的旁通和支管上的球阀。

During pipeline operation process,a series of problems is easily to occur in high-pressure ball valves of kinds of branch pipelines and bypasses,such as valve leakage and being unable to inject grease for maintenance. According to the feature that the pressure of one end of the ball valve can be discharged,a device to block and replace ball valve in axial direction from the end of the valve is developed. The device consists of a blockage head,an operational rod,a high pressure seal chamber,split type beams,connection bolts,a ring clamp,etc. In the sealing state of the seal chamber,the blockage head is pushed through the needed replaced valve into the blockage position of the pipe by the operational rod.Next,rotating the operational rod squeezes the blockage head causing it expanding to block the pipe. Then the valve can be replaced. The device is designed and manufactured according to DN50 ball valve dimension,and its field test is successful. This device has the advantages such as non-stop transmission of trunk pipeline and no welding and ignition work needed. It can be applied to replace ball valves in branch pipeline and bypass under the pipeline operation condition in high pressure.