What are the cleaning methods of air conditioning copper fittings before assembly

The operation effect of the multi-line not only depends on the equipment, but also has a close relationship with the installation factors such as the installation of the refrigerant tube and the filling of the refrigerant agent. This method focuses on solving the following key problems in construction:

1, the selection of refrigerant pipe should be dephosphorized seamless copper pipe, copper pipe below Φ19.05 using coil, reduce copper pipe joints, specifications greater than Φ19.05 using straight pipe;

2, the construction of refrigerant pipe must ensure that the pipe is dry, and try to avoid construction in rainy days;

3, the refrigerant pipe welding process must be filled with nitrogen protection, and according to the actual construction experience summed up a reasonable pressure value, to avoid the nitrogen flow is too large, the welding is easy to produce sand holes, the flow is too small, it will produce too much oxide film nitrogen must flow from the welding disadvantages. A feasible method of nitrogen filling is proposed.

4, the specified refrigerant pipe in the welding of various installation methods corresponding to the welding mode, mainly to prevent burns or sand holes and leakage.

5, put forward the selection and installation of diverging pipe to avoid the phenomenon of uneven hot and cold between multiple sets and multiple lines

6. Standardized the process and standard of system purge, airtight test, drying and flushing refrigerant after installation.

Process principle:

Using a solder with a melting point lower than copper, the joint gap is filled by capillary action after melting, and the joint is connected with the base metal by mutual diffusion, and the atomic bond is achieved by mutual diffusion of liquid solder and solid metal. And the two materials work together. By setting the form and position of the support and hanger reasonably, the split pipe is controlled in the horizontal or vertical state to ensure the balanced flow distribution.

Construction process and key points of operation

Construction process flow:

Construction preparation → Material selection → check piping size → Copper pipe laying → brazing connection → pipeline flushing → airtight test → pipeline insulation → vacuum drying → refrigerant addition → commissioning operation

Operating points:

1 Construction preparation:

1.1 On-site check:

Before installation, first check the drawings to check whether the pipeline layout is crossed and contradictory with the structure and other professional pipelines; Check whether the position and elevation of the embedded parts, support and casing of the pipeline are correct. Check whether the holes reserved during early civil construction are accurate and complete.

1.2 Materials:

Familiar with the various materials used in the project, including copper pipe, split pipe, steel, insulation, etc., timely and accurately check the materials provided by the material procurement department to confirm whether they meet the construction requirements.

1.3 Personnel preparation:

According to the amount of work to determine the number of construction personnel, safety and technical disclosure.

2.2 Material Selection

2.2.1 Refrigerant pipeline audit:

1) Material: dephosphorized seamless copper tube, extrusion process.

2) Appearance: the internal and external surfaces of the pipeline should be free of pinholes, cracks, peeling, foaming, copper powder, carbon layer, green rust, dirt and serious oxide film, and are not allowed to have obvious scratches, pits, spots and other defects.