大口径法兰是法兰中的一种，在机械行业中普遍使用和推广，得到用户的好评和青睐。大口径法兰的用途广泛，使用范围根据不同的特点进行确定，多用于介质条件比较缓和的情况下，如低压非净化压缩空气、低压循环水，它的优点是价格比较便宜。卷制法兰适用于公称压力不超过2.5MPa的钢管道连接，卷制法兰的密封面可以制成光滑式,凹凸式和榫槽式三种.光滑式卷制法兰的应用量最大，其他两种方式的卷制法兰在使用中也是比较普遍的。卷制法兰包括很多种类型和型号，对焊钢法兰用于法兰与管子的对口焊接，主要使用在焊接技术中，表现良好的使用特点和性能，其结构合理,强度与刚度较大，经得起高温高压及反复弯曲和温度波动,密封性可靠，公称压力为0.25～2.5MPa的卷制法兰采用凹凸式密封面。卷制法兰主要应用的环境是适宜的，需要根据具体的情况确定，保证大口径法兰的具体使用价值和性能，承受住高温高压。
Large diameter flange is one of the flanges. It is widely used and popularized in the machinery industry. It has been praised and favored by the users. The large caliber flanges are widely used and their application ranges are determined according to their different characteristics. They are mostly used for relatively mild medium conditions, such as low pressure non purified compressed air and low pressure circulating water, which has the advantage of low price. Rolling flange for nominal pressure of not more than 2.5MPa of steel pipe connection, flange sealing surface rolling can be made smooth type, concave type and trough type of three. Application of smooth rolling type flange, flange coiling the other two ways is relatively common in use. Rolling flange including many types and models, butt welding steel flanges for butt welding flange and pipe, mainly used in welding technology, performance characteristics and good performance, reasonable structure, strength and stiffness to withstand high temperature and high pressure and repeated bending and temperature fluctuation, reliable seal, nominal pressure 0.25 ~ 2.5MPa rolling flange seal surface using bump. The main application environment of rolled flange is suitable. It needs to be determined according to the specific circumstances to ensure the specific use value and performance of large diameter flange, and withstand high temperature and high pressure.