呼吸阀类似于单向止逆阀，它只能向外呼气，不能向内吸气，当系统内压力升高时，气体便经过呼吸阀向外放空，保证系统的压力恒定。一般它被用在常压或低压贮罐上。焦炭塔的呼吸阀有两个用处：一、放水时，吸气，以利塔内存水顺利放出；二、呼气，蒸汽赶空气时，用以放净空气，脱水放汽时，用以检查塔内是否为正压。呼吸阀是用于安装原油、汽油、煤油、轻柴油、芳烃等固定顶式储罐上的主要安全设备，是起蒸发损耗与保护储罐在受超压或 真空时免遭破坏的作用。此阀通常与阻火器配套使用。当外界大气压力大于罐内压力时 就会往罐内补气 从而达到内外压力的平衡。呼吸阀是固定在储罐顶上的通风装置，以保证罐内压力的正常状态，防止罐内超压或真空使储罐遭受损坏，也可减少罐内液体挥发损失。根据中国《石油化工设计防火规范》（GB50160-92）的规定：“甲、乙类液体的固定顶罐，应设阻火器和呼吸阀”，结构紧凑、重量轻、通风量大、泄露小等优点。产品有单呼阀、单吸阀、呼吸阀，各种结构型式均可与阻火器组合构造，也可配制所需的接管。
德国福林阀门(FRING)是亚太地区流体控制领域的主要生产和供应商之一，公司总部位于法兰克福，公司致力于科研开发流体控制阀门，生产流体控制设备系统，在许多个国家均有生产阀门基地。公司产品的用户涉及石油、化工、电力、冶金、制药、食品、水处理、市政给排水、天然气、造纸、电子工业、楼宇、机械设备配套等领域。
The German FRING valve is of the Asian and Pacific area fluid control domain one of main production and suppliers, the Base company is located at Frankfurt, the company devotes to the scientific research development fluid control valve, the production fluid control device system, has the production valve base in many countries. The company product s user involves the petroleum, the chemical industry, the electric power, the metallurgy, the drugs manufacture, food, the water treatment, the municipal administration to give draining water, the natural gas, the papermaking, the electronics industry, the building, the mechanical device necessary and so on domains.
The German FRING valve main product includes: Electrically operated valve, air operated valve, high temperature high pressure valve, ball valve, gate valve, reed valve, cut-off valve, check valve, regulating valve, solenoid valve, safety valve, needle valve, condensate trap |、 The draining valve, the stopcock, the diaphragm valve, the duck mouth valve, puts the material valve, the discharge valve, the respiration valve, the filter, the fire barrier, the throttle valve, the angle place valve, the by-pass valve, the wash water valve, the mud valve, the trip valve, the pressure relief valve, the tube to clamp the valve, the plunger valve, the bottom valve, to regard the mirror, the flange, the water power control valve, and so on serial productses.
中国总代理：上海前泽阀门有限公司
电话：021-31265668 联系人：陈深安
手机：13661441718
