How to remove dust for plasma cutting of SSAW steel pipe?

When plasma cutting SSAW (Spiral Submerged Arc Welded) steel pipes, managing dust removal presents several challenges. This article will briefly introduce how to remove dust for plasma cutting of SSAW steel pipe.

Dual Direction Airflow: 

During cutting, the plasma gun nozzle blows air in two opposite directions, causing smoke and dust to emerge from both ends of the steel pipe. This makes it difficult for a suction port installed in only one direction to effectively capture all the smoke and dust.

Cold Air Infiltration: 

Cold air enters the suction port from outside the machine through gaps, increasing the total volume of air and smoke inside the steel pipe beyond the capacity of the dust collector to effectively inhale. This prevents complete absorption of the cutting smoke and dust.

Distance from Suction Inlet: 

The cutting point is far from the dust suction inlet, making it challenging for the suction force to draw the smoke and dust efficiently.

To address these issues, the following design principles for the dust cover are recommended:

Adequate Air Volume: 

Ensure that the air volume inhaled by the dust collector exceeds the total amount of smoke, dust, and air inside the pipe. This should create a negative pressure cavity inside the steel pipe, minimizing the entry of outside air and drawing the fumes into the dust collector.

Smoke and Dust Blocking: 

Position a barrier after the cutting point to prevent cold air from entering the steel pipe at the suction port. This helps maintain a negative pressure cavity inside the pipe, preventing smoke and dust from escaping. The design must be reliable, should not hinder normal production, and should be convenient to use.

Optimal Suction Port Design: 

The suction port's shape and location should maximize the capture of smoke and dust inside the steel pipe. Adding a baffle after the plasma gun's cutting point helps retain smoke and dust inside the pipe, allowing complete removal after a period of buffering.

Specific Measures

Soot Baffle Installation: 

Install a soot baffle on an accompanying trolley inside the steel pipe, approximately 500mm from the plasma gun's cutting point. After cutting, allow time for the baffle to absorb all the soot. Ensure the fume baffle is accurately positioned at the cut-off point.

Alignment with Steel Pipe Rotation: 

To ensure the accompanying trolley supporting the fume baffle rotates consistently with the steel pipe, match the wheel angle of the trolley with the inner roller angle.

This method is effective for plasma cutting large-diameter spiral welded pipes with diameters of about 800mm. For pipes with diameters less than 800mm, smoke and dust do not emerge from the pipe direction, eliminating the need for an internal baffle. However, an external baffle must be installed at the fume suction port to block the entry of cold air.