Spiral submerged arc welding method of SSAW pipe

Spiral submerged arc welding (SSAW) steel pipes are extensively used in petroleum, chemical, and natural gas industries. The welding method is crucial for ensuring the quality and reliability of these steel pipes. This article outlines the welding method for SSAW steel pipes.

Welding Equipment for SSAW Pipes:

The welding of SSAW pipes requires specialized equipment, including:

- Welding Power Sources: Core equipment that provides stable welding current and voltage.

- Wire Feeders: Essential for feeding the welding wire.

- Traveling Mechanisms: Ensures the pipe moves smoothly during welding.

Welding Process of SSAW Pipes:

- Preparation Stage:

Clean and polish the steel pipe to remove impurities such as oil, rust, and scale.

Ensure the surface is free from contaminants to maintain welding quality.

- Assembly Stage:

Align and assemble the two sections of the steel pipe to be welded.

Ensure the gap between the sections is even and the weld seams are properly aligned.

- Welding Stage:

Fix the assembled steel pipe on the traveling mechanism.

Perform the welding using the submerged arc welding method, paying attention to the following points:

1. Control of Welding Current and Voltage:

Adjust the current and voltage based on the material and thickness of the steel pipe.

Avoid too high current to prevent burn-through or undercut, and too low voltage to avoid poor fusion or porosity.

2. Control of Welding Speed:

Maintain a stable welding speed.

Avoid welding too fast, which can cause poor fusion or porosity, and too slow, which can cause burn-through or undercut.

3. Control of Welding Wire Position:

Precisely control the position of the welding wire to ensure the quality of the weld.

Incorrect wire positioning can result in defects like pores or slag inclusions.

- Post-Welding Quality Inspection:

After welding, inspect the steel pipe for quality, including:

Appearance Inspection: Check for visible defects.

Non-Destructive Inspection: Use techniques like ultrasonic testing to detect internal defects.

Repair or Re-Weld: Address any defects found during inspection to ensure the integrity of the pipe.

Conclusion:

The welding method for SSAW steel pipes is critical for ensuring their quality and reliability. Proper control of welding parameters such as current, voltage, and speed, as well as precise wire positioning, are essential. Post-welding quality inspections are necessary to confirm the weld's integrity and the pipe's overall quality.