Research On Ventilation And Dust Control System Of Large Multi-span Welding Workshop

The release of welding dust will cause serious pollution of the work environment in the welding plant and damage the health of the practitioners.With the development of large-size welding workshop and the improvement of welding efficiency,the plant dust production increased significantly.The large space increases the difficulty of ventilation and dust controlled in the workshop and adds welding workshop pollution.Severe retention of welding smoke brought serious challenges to dustproof and ventilation in large welding workshop.The traditional ventilation way can not already meet the requirement of the modern large workshop.By the investigation of a welding workshop,the study its natural geographical environment parameters,the structure and size of workshop,distribution of the welding point,amount of welding smoke,welding power,ventilation and pollution situation,the main pollution sources be sure.And then amount of welding smoke radiation is calculated.Base on the size and structure of real welding workshop,high quality hexahedron mesh by using ICEM.The spread and stratification characteristics of welding plume is studied.The layered model of welding plumbing is put forward.The suitable model of large welding plant is established.By calculating the parameters of the smoke at the top of the welding point at 1 m,the parameters of the welding dust surface are determined.And then the calculation model of the natural ventilation including natural ventilation way,displacement ventilation and push-pull ventilation are built.Finally,the location and size of inlet and outlet of the super large plant are sure.The three-dimensional simulation experiment of the welding dust flow in the workshop was carried out by using the CFX calculation software to study the spatial distribution of the parameters of the welding dust and dust in the large-scale welding plant.The dustproof effect under the most unfavorable natural ventilation condition is studied,and the numerical simulation of the ventilation model of the replacement ventilation of the large welding plant is carried out.The blowout ventilation in the vertical direction is studied in detail.And the dustproof effect of three kinds of ventilation was compared.To the welding dust in the workplace air time weighted average allowable concentration of 4 mg/m~3look upon as the standards.The results show that Down into the natural ventilation air volume more than 90 m~3/s gets the dustproof deep of 150m,which is suitable for the size of less than 150 m plant welding dust control.The isplacement ventilation of both sides of the air flow at 60m~3?90m~3is best.Not only make full use of the ventilation characteristics of the replacement of ventilation,but also to ensure the separation of welding smoke.Push-pull ventilation at 50m~3/s makes the factory air in the average concentration of welding dust less than 4 mg/m~3.By comparing,push-pull ventilation as the main ventilation adopted has the feasibility and t superiority in large welding workshop.The push-pull ventilation of vertical direction make welding smoke and dust leave the workshop under the smaller air volume,get the high levels of pollution,improve the efficiency of dust removal and provides reference for the application of large space ventilation.