Common Connection Ways of Building Pipeline 1. Threaded connection Thread connection is made of threaded pipe fittings. Galvanized steel pipes with diameter less than or equal to 100 mm are suitable for threaded connection, mostly for open pipes.Steel-plastic composite pipes are usually connected by threads.Galvanized steel pipes should be connected by threads. The surface of galvanized layer and exposed threads damaged by threading should be treated with anticorrosive treatment. Flanges or jacket-type special fittings should be used to connect the galvanized steel pipes and flanges. The welds between galvanized steel pipes and flanges should be galvanized twice. 2. Flange connection Large diameter pipelines are connected by flanges. Flanges are generally used in the main road connecting valves, check valves, water meters, pumps and other places, as well as pipelines that need to be disassembled and repaired frequently.If galvanized pipes are joined by welding or flange, secondary galvanizing or corrosion protection shall be carried out at the welding site. 3. welding Welding is suitable for non-galvanized steel pipes, mostly for concealed pipes and large diameter pipes, and is widely used in high-rise buildings.Special joint or welding can be used for copper pipe connection. Socket or casing welding should be used when pipe diameter is less than 22mm. Socket should be installed in the direction of medium flow. Counterpart welding should be used when pipe diameter is greater than or equal to 2mm.The stainless steel pipe can be socket welded. 4. Groove connection (clamp connection) The groove connection can be used for galvanized steel pipe whose diameter is greater than or equal to 100 mm in fire fighting water, air conditioning cold and hot water, water supply and rainwater systems. It has the characteristics of simple operation, no influence on the original characteristics of the pipeline, safe construction, good system stability, convenient maintenance, labor saving and time saving. 5. Sleeve connection Aluminum-plastic composite pipes are generally crimped by threaded clamp sleeves.The fittings nut is sleeved at the end of the pipe, and the inner core of the fittings is sleeved in the end. The fittings and nuts can be tightened with a wrench.The connection of copper pipe can also be pressed by thread clamp sleeve. 6. Compression connection Stainless steel clamping pipe fittings connection technology replaces traditional water supply pipe connection technology such as threading, welding, gluing, etc. It has the characteristics of protecting water quality sanitation, strong corrosion resistance and long service life. During construction, the socket fittings with special sealing rings will be connected with pipelines, and the socket fittings will be tightened and tightened by special tools. In construction, it has the advantages of convenient installation, reliable connection and long service life.Economic and reasonable advantages. 7. Hot melt connection The PPR pipe is connected by hot melt. 8. Socket connection It is used to connect cast iron pipes and fittings for water supply and drainage.There are two kinds of flexible connections and rigid connections. The flexible connections are sealed by rubber rings, the rigid connections are sealed by asbestos cement or expansive fillers, and the important occasions are sealed by lead.