5. If the valve and fan interaction should be used with double micro-switch device. 6. The valve should be steel blade thickness of 2 ~ 6mm, the body of non-combustible materials factory fire dampers, rotating parts should be corrosion-resistant metallic materials, and flexible rotation. Shall not be less than the thickness of the valve housing 2mm. Yi Rong parts shall comply with recognized standards of the fire department. Damper is now gradually widely used in major construction industry, as we are now increasing awareness of fire, so the major building fire safety requirements are also rising, which requires to have a good fire dampers feature on the main role dampers, we know how much today as we detail below: damper that is used to block the smoke and flames from the fire zone by and within a certain time to meet the fire resistance stability and refractory integrity pleading valve. When construction materials fires ballistic flue damper, fire along the ventilation, air conditioning system of rapid extension of the case is a serious loss of many. In order to reduce the fire caused damage to a minimum level of damper 70 ℃, it is necessary to employ a useful fire, smoke control measures in order to seize the fire extension, and fire dampers in ventilation, air conditioning and smoke control system in a reasonable equipment, then played a primary effect. Fire dampers, fire dampers fvd, Plumper ventilation equipment (certified merchants) are provided by Shandong Dezhou Plumper ventilation plant. Dezhou Plumper ventilation plant (0) in Shandong Dezhou City, Shandong Wu Tun right. Scraps and development in the wave of market economy, the current rich ventilation equipment has a high profile in the fan, ventilation equipment, and enjoy a good reputation. Rich ventilation equipment made the whole network business alliance certification, marking our service and management level has reached a new height. Rich ventilation equipment staff willing to work with all people of insight and common development, for a better future.