First, the choice of pipeline connection mode depends on what material the pipeline is made of. 1, steel pipe connection: mainly welding, flange connection and threaded connection. 2. Connection of cast iron pipes: there are two types: rigid connection and flexible connection. 3. Connection of plastic pipes: Bonding and welding are widely used.

Second, pipes with different pressure grades should be connected through pressure regulating devices. When it is possible to exceed the maximum allowable working pressure, a safety protection device should be set to prevent the pipeline from overpressure.

If you want to know more, you can buy a national training textbook for pressure pipeline design approvers for reference.