法兰密封面的型式有三种：平面型密封面，适用于压力不高、介质无毒的场合；凹凸密封面，适用于压力稍高的场合；榫槽密封面，适用于易燃、易爆、有毒介质及压力较高的场合。不同性质的法兰管件在不同的领域中具有良好的产品性能，适应的场合和空间不同，产生的功效也会不同。
There are three types of flange sealing surface: flat sealing surface, which is suitable for situations with low pressure and non-toxic medium; concave and convex sealing surface, which is suitable for situations with slightly higher pressure; mortise sealing surface, which is suitable for situations with flammable, explosive, toxic medium and high pressure. Flanged pipe fittings of different properties have good product performance in different fields, and the effect will be different when the occasion and space are different.