ANALYSES AND PROTECTION OF WATER HAMMER IN GAS-DISSOLVED LIQUID PIPELINE

摘要

For varies reasons, air enters the liquid pipeline and/or the liquid vaporize, thus the air/vapor exists in liquid pipeline. When the pipeline is shut down, the air/vapor gather together and form vapor cavity somewhere in pipeline. The vapor cavity is harmful for pipeline restart by causing downstream equipment malfunction or sharp pressure increase in pipeline. Presented in this paper is the analysis of hydraulic states of gas-dissolved liquid pipeline using rigid water hammer theory. The result show that when the gas-dissolved liquid pipeline restarts, the trapped vapor is compressed and the pressure in pipeline increase sharply, which is very harmful for pipeline safety. Installation of vapor-eliminating device on suitable location is one of the common means to protect pipeline from damage. The Author designs a novel automatic air-eliminating device, which can automatically discharge vapor and prevent liquid spill. The device is granted as national patent.