What should be paid attention to when connecting galvanized steel pipes

The connection method specification of galvanized steel pipes depends on the type of connection method. Generally, there are several types, flange connection, clamp groove connection, and welding. In the actual connection of galvanized steel pipes, welding is a more commonly used connection method. Although welding takes a long time, the quality is the best among the three methods; the clamp groove connection is more convenient. After the two steel pipes are processed, the grooves are matched and aligned, and then the clamps are used to reinforce the hook points; the flange connection is to fix the two steel pipes on a flange plate respectively, and then fix the two flange plates, and the two steel pipes are passively connected.

The following are the specific prevention and control phenomena and measures that should be taken in the specification of galvanized steel pipe connection methods.

First, improper connection of galvanized steel pipes

1. Leakage, water leakage, and moisture return at the pipe mouth;

2. No re-galvanizing at the welding point between the galvanized steel pipe and the flange

Second, preventive measures for improper connection of galvanized steel pipes

1. In the selection of pipes, high-quality ones should be selected; the connection method should be finally determined by the design specification requirements and the size of the pipe fittings. The construction should be strictly carried out according to the standard steps and processes of various connection methods.

2. When the DN is not greater than 100 mm, the galvanized steel pipe should be connected by a threaded connection.

3. Before connecting the galvanized steel pipe, first screw the galvanized steel pipe by hand to check its tightness, and keep enough margin to tighten the pipe fittings.

4. Wrap the filler in a clockwise direction and wrap it evenly.

5. When the DN is greater than 100 mm, the galvanized steel pipe can be connected by welding flange.

6. After welding the flange, secondary galvanizing is required. If you are not sure about the cutting size of the relevant parts, you can pre-assemble them first, and then perform secondary galvanizing if there is no problem.

7. When the two flanges are connected, they should be parallel. Do not force the non-parallel flanges to connect.

8. The gasket should be placed between the two connected flanges. Its material and thickness should meet the specifications of design or construction. The gasket should be made into a handle shape before installation, and it should not protrude into the flange. In addition, its edge should be as close to the bolt hole as possible. Do not install two gaskets or install the gasket sideways.

9. For the bolts connected by flange installation, their length and diameter must meet the standards. In terms of direction, the installation must be consistent, that is, the nuts should be on the same side.

10. After the installation of the galvanized steel pipe, a water pressure test should be carried out, mainly to check whether there will be leakage at each connection. If this situation occurs, it should be marked and tested again after the repair is completed until the inspection results are completely qualified.