Welding process of spiral welded steel pipe

Basic concepts of spiral welded steel pipe:

Spiral welded steel pipe (SSAW) is a steel pipe made from steel plate or strip steel, rolled into a tube shape, and then continuously welded. It is widely used in petroleum, natural gas, chemical industry, heating, water transportation and other industries. It is characterized by high production efficiency, stable quality and low cost, so it is very popular.

Preparation work before welding of spiral welded steel pipe:

To ensure welding quality, we must first make preparations before welding, which mainly include the following:
1. Steel pipe cutting

Before cutting the steel pipe, it is necessary to ensure that its surface is clean and free of oil stains to avoid problems such as pores and inclusions. In addition, the cut must be straight and consistent in width to avoid deviations in subsequent welding.

2. Bevel processing
Grooving is a very critical step in welding. The geometric size and shape of the welded groove will directly affect the quality and overall strength of the weld. Therefore, it must be processed according to the requirements to ensure that the groove size and shape meet the requirements.

3. Surface cleaning treatment

Before welding, the surface of the steel pipe must be cleaned to remove oil, rust and other impurities to ensure welding quality and subsequent quality inspection.

Welding parameter selection of spiral welded steel pipe:

The selection of welding parameters for spiral welded steel pipes is the key to determining the quality and output of the weld, mainly involving current, voltage, speed, etc. The best welding parameters should be selected according to the material type, thickness, cross-sectional shape, welding environment and other conditions.

Precautions for welding of spiral welded steel pipes:

In the actual operation of spiral welded steel pipes, the following matters should also be paid attention to:

1. Bevel distance
The groove distance should be kept as close as possible to the weld, which can minimize the heat-affected zone and reduce welding distortion.

2. Bevel position
Try to place the groove as low as possible to avoid sparks from splashing onto the groove during the welding process, causing quality problems.

3. Welding speed
The welding speed of spiral welded steel pipes should be moderate. If welding is too fast, the weld will be weak, and if welding is too slow, the weld will be insufficiently fused and of poor quality.

4. Welding form
There are two welding forms of spiral welded steel pipes, one is internal welding and the other is external welding. Internal welding is mainly used in water pipes, air pipes, hot water pipes and other fields; external welding is used in large-diameter gas pipelines, with the advantages of high production efficiency and stable quality.

Summarize:

The welding process of spiral welded steel pipes is a multi-faceted technology that requires operators to have sensitivity and expertise in every detail. Through the introduction of this article, readers can better understand the welding technology and precautions of spiral welded steel pipes, and improve the quality and efficiency of steel pipe welding.

Go here to learn more: Seamless vs Welded pipe