(1) The return air flow generally contains gas. When it enters the local ventilator again, due to the high-speed rotation of the fan blades, friction will occur with the dust in the wind flow to generate sparks, which may ignite the gas. (2) As part of the cycle of polluted air to the heading face, so that the concentration of gas and dust heading face increasing may cause gas, coal dust accidents. (3) Deteriorating the climatic conditions of the excavation face and damaging the health of the staff. The main reasons for the circulation of wind are: (1) The local ventilator is improperly installed, that is, it is too close to the return air inlet of the heading face. Due to the diffusion of the wind flow, part of the return air enters the fan. (2) The amount of suction of the local ventilator is greater than the amount of air supplied to it by the full wind pressure. The measures to prevent circulating wind are: (1) The pressure local ventilation fan and starting device must be installed in the air inlet, not less than 10 meters from the return air outlet. (2) The suction air volume of the local ventilator must be less than the air volume supplied by the full wind pressure. (3) Always check whether circulating air is generated. The simple method of inspection is to stand on the side of the fan and smash the chalk end by hand. If the chalk end is observed to float toward the fan suction port, it means that the circulating wind has occurred. Otherwise, Indicates no circulation wind. Heat Preservation Anticorrosive Pipe Series Products
Anticorrosive and heat insulation fittings include anticorrosive insulation elbow, anticorrosive thermal insulation three links, anticorrosive thermal insulation bend pipes, anticorrosive and heat insulation different diameter pipes and so on. The anticorrosive and heat insulation pipe fittings are closely combined with high density polyethylene outer pipe, polyurethane foam insulation layer and inner work pipe body.
The heat insulation elbow is mainly used for the steering of the heat preservation pipe, which is generally used with the insulation pipe. It is used for compensation according to the heat insulation engineering pipeline design, so that the elbow can also have enough insulation performance, the standard elbow angle is 30, 45, 60, 90 degrees. Widely used in liquid and gas pipeline network, chemical pipeline insulation engineering oil, chemical, central heating network, central air conditioning ventilation pipe, municipal engineering pipe turning place. The main implementation standard CJ/T200 - 2004 "technical conditions for prefabricated direct buried steam insulation pipe for urban heating", CJ/T104---2005 "technical specification for direct buried steam pipeline for urban heating", SY/T114-2000, SY/T115-2001 "high density polyethylene polyurethane foam insulation Steel Pipe".
Pipeline anticorrosion refers to measures to slow down or prevent pipelines from being eroded and metamorphosed by chemical, electrochemical, or microbial metabolism.
Heat Preservation Pipe,Anti Corrosion Pipe,Underfloor Heat Preservation Pipe,Underfloor Anti Corrosion Pipe HeBei GuangHao Pipe Fittings Co .,LTD (Cangzhou Sailing Steel Pipe Co., Ltd) , https://www.guanghaofitting.com
When a local ventilator is used to ventilate the heading face, the local ventilator sends the wind flow to the heading face, and the return air after cleaning the working face has a part or all of the same into the same local ventilator. . This situation is often encountered downhole. The hazards of circulating wind are: