Various filter works and the advantages and disadvantages: gravity settling chamber: by gravity to separate dust particles from a gas stream, after the dust stream entering gravity settling chamber, the flow rate of the rapid decline in the production of ventilation ducts in Hangzhou, in laminar or close layer state of the stream next campaign, in which the hopper dust slowly settling under gravity. Applicable diameter> 50μm. Leakage Rate Testing and inspection should be qualified special measuring instruments or measuring devices used in line with national standards in force measurement device (flow measurement throttling device) shall erection. Leakage testing device can be ducted or plenum type. Duct testing devices using orifice metering device for ventilation ducts, air-chamber test device using a nozzle for ventilation ductwork metering elements, the measured and design values ??given the last measure of not less than 10 percent qualified. In some large hotels malls ventilation pipe processing, basement smoke control engineering, clean room engineering and ventilation and air conditioning engineering and other occasions, smoke control system is essential. Hangzhou ventilation pipe processing, building ventilation pipe processing, Xiaoshan District, Hangzhou Xingda ventilation pipe supplied by ventilation equipment. Hangzhou Xingda ventilation equipment (www.tz1288.com/shop/index_6525.html) located 192 萧绍东 Road, Xiaoshan District, Hangzhou, Zhejiang Province. Scraps and development in the wave of market economy, currently has a high profile Xingda ventilation in fan, ventilation equipment, and enjoys a good reputation. Xingda ventilation made the whole network business alliance certification, marking our service and management level has reached a new height. Ventilation Xingda staff is willing to all people of insight and common development, for a better future.