Common Connection Method of Pipeline

According to the purpose and the pipe material, the commonly used connection methods of the construction pipeline are: threaded connection, flange connection, welding, groove connection (clamp connection), card sleeve connection, compression connection, hot melt connection, etc.

1. Threaded connection

Threaded connection is the use of threaded pipe fittings. Galvanized steel pipes with a diameter of less than or equal to 100mm should be connected with threaded pipes. They are mostly used for surface-mounted pipelines.

Steel-plastic composite pipes are generally connected by threads. Galvanized steel pipes are connected by threads, and the surface of the galvanized layer and the exposed threads that are damaged during threading should be treated with anti-corrosion treatment.

2. Flange connection

Flange connection is to fix two pipes, pipe fittings or equipment on a flange plate respectively, then add a flange gasket between the two flange plates, and finally tighten the two flange plates with bolts. It is tightly integrated.

Pipes with larger diameters are connected by flanges. Flange connections are generally used in the main road connecting valves, check valves, water meters, pumps, etc., as well as pipe sections that require frequent disassembly and maintenance.

3. Welding

Welding is suitable for non-galvanized steel pipes. It is mostly used for concealed pipes and pipes with larger diameters, and is often used in high-rise buildings. Copper pipe connection can adopt special joint or welding. When the pipe diameter is less than 22mm, socket or sleeve welding should be used.

4. Groove connection (clamp connection)

Grooved connectors can be used for firefighting water, air-conditioning cold and hot water, water supply, rainwater and other systems with a diameter greater than or equal to 100mm galvanized steel pipes. It has simple operation and does not affect the original characteristics of the pipeline, construction safety, and system stability. , Convenient maintenance, labor and time saving and other features.

5. Card sleeve connection

A connection method in which the pipe is pressed tightly on the pipe with a lock nut and a threaded pipe fitting. Put the fitting nut on the end of the pipe, then put the fitting inner core into the end, and use a wrench to tighten the fitting and the nut. The connection of copper pipes can also be crimped with threaded ferrules. The ferrule joint is not suitable for places with high temperature and vibration.

6. Compression connection

The stainless steel compression pipe connection technology replaces the traditional water supply pipe connection technology such as thread, welding, and glue connection. It has the characteristics of protecting water quality and sanitation, strong corrosion resistance, and long service life. Socket pipe fittings with special sealing rings will be installed during construction. It is connected with the pipeline, and the nozzle is compressed with a special tool to play a role of sealing and fastening. The construction has the advantages of convenient installation, reliable connection, and economical reasonableness.

7. Hot melt connection

Hot melt connection is widely used in the connection of new pipes and fittings such as PP-R pipes, PB pipes, and PE-RT pipes.
Key points for the hot-melt connection of pipe fittings: After the heating time is reached, immediately remove the pipes and fittings from the heating jacket and the heating head, and insert them straight and evenly to the marked depth without rotation to form a uniform flange at the joint.

Hot-melt connection mainly includes: hot-melt socket connection and hot-melt butt welding connection. Hot-melt connection has the advantages of simple connection, long service life, and not easy to corrode.