Research And Optimization Of Breathing Valve Performance Based On Hydraulic Sealing

The storage tank is an essential equipment in the petrochemical industry.The breathing valve and hydraulic safety valve are important accessories for the safe breathing system of the storage tank.The safe breathing system provides a safe ventilation path for the storage tank.Too large causes structural damage,and at the same time can reduce the evaporation loss of the medium in the storage tank.The breathing valve is the core of a safe breathing system.The existing breathing valve uses a mechanical structure to achieve sealing.This type of sealing can cause problems such as inaccurate opening pressure of the breathing valve,opening failure and inadequate sealing when the valve disc of the breathing valve is loosely deformed or the sealing surface is contaminated and damaged.The environment is polluted and there is an accident of failure and damage caused by the overpressure operation of the storage tank.The hydraulic safety valve adopts liquid sealing technology and has a good sealing effect,but the traditional structure is only suitable for emergency opening.After opening,the sealing liquid is discharged out of the valve.After a single use,the sealing liquid needs to be manually injected to restore the function.Based on the structural principles and experience of traditional mechanical breathing valves and hydraulic safety valves widely used at present,this topic summarizes the main defects of current mechanical breathing valves and hydraulic safety valves,and improves and optimizes hydraulic pressure based on the principle of liquid sealing of hydraulic safety valves The internal structure of the safety valve strengthens the gas-liquid two-phase flow separation function by setting the gas-liquid separation structure,realizes the separate circulation of the sealing liquid by setting the return structure,and realizes a new type of breathing valve based on the liquidsealing technology.The new breathing valve has a complete sealing performance in a sealed state,and at the same time,the sealing liquid is not entrained with the air flow after the breathing valve is opened,which realizes recycling and automatic reset.Through the finite element flow field analysis of the gas-liquid separation structure and the return structure,the opening pressure,flow rate distribution and water volume distribution of the breathing valve were obtained,the rationality and effectiveness of the structure were verified,and the design parameters of the new structure were optimized.According to the relevant national standards of breathing valve products,build an experimental test platform.Experimental tests such as cracking pressure and ventilation were carried out on the breathing valve based on hydraulic seals.The experimental results are in good agreement with the results of finite element simulation and simulation.The indexes of ventilation and cracking pressure meet the requirements of national standards.On-site operation test was carried out in a petrochemical storage tank.The test results prove that the breathing valve based on the principle of liquid sealing has good sealing performance,and there is no problem of micro leakage or opening failure.There is no overflow of the sealing liquid,which can realize safe and reliable operation for a long period.