The Xiris Blog

Using Cameras When Welding Spiral Pipe: Processing and Tacking

Posted by Cameron Serles on Wednesday, August 16, 2017 @ 10:18 AM

Helical (or Spiral) Submerged Arc Welding (HSAW) allows for larger, thinner-wall welded pipe, but this benefit has a cost—a higher chance of welding defects.

By enabling greater visibility and control during processing and tacking, high dynamic range (HDR) weld cameras are a powerful tool to counter this risk.

The Advantages of HSAW

HSAW has a unique capability for producing large diameter pipes for flammable and nonflammable liquid transportation. While longitudinal pipe welding is limited to approximately 42” (1.1 m) outer diameter due to the size of the feedstock sheet, helical pipe welding is only limited by the size of the equipment, allowing pipes as large as 140” (3.6 m) outer diameter to be manufactured.  

Helically welded pipe also has a distinct advantage over longitudinally welded pipe because the radial stress in the weld seam is not concentrated along a single axis but instead rotates around the circumference of the pipe, creating a more-even stress distribution. This advantage allows for thinner tube wall construction using more economical, non-high-strength materials.

Limiting Defects with HDR Weld Cameras

Spiral welded pipe is made using either one-stage or two-stage weld processing.  While both processes begin with the incoming skelp coil of material being unwound, flattened, trimmed, squared, and then fed into the forming  stage, in one-stage processing, the forming process is immediately followed by simultaneous inside and outside Submerged Arc Welding.

In two-stage processing, the material is formed and tack welded into the pipe body shape by a gas metal welder prior to the Submerged Arc Welding process. The tack welding stage is critical for the quality of the pipe because misalignment of the initial tack will cause defects when further processed during the Submerged Arc Welding stage. Numerous factors can cause misalignment, including defects in the metallurgical properties of the feedstock, gaps between sheets, misalignment of the welding heads, or dull tooling during the processing of the skelp coil.

With the latest in camera and software technology, the Xiris XVC-1000e high-dynamic-range weld camera permits the operator to see the spiral pipe feedstock,  the weld head, and torch location relative to the weld seam during the welding process. By monitoring the images directly, an operator can make adjustments to the material inputs or torch position to quickly correct the fault before the defect propagates throughout the length of the weld.  The camera’s robust, IP65-rated enclosure allows it to survive the harsh environments of HSAW pipe mills.

Additionally, the XVC-1000e can be used with Xiris’ seam tracking software, as shown in the figure below. The seam tracker software identifies the location of the welding head and the arc contact with the material and the material seam, detecting fluctuations in alignment. With such software, out-of-alignment conditions can automatically alert the operator to make process-control adjustments or even provide closed-loop feedback to automatically move the torch back into position.

XVC-1000e with Seam Tracker Software

Summary

Adding a Xiris XVC-1000e weld camera to an HSAW pipe mill can help operators monitor the feedstock material forming process and alignment to the welding torch, ensuring that minimal defects occur during the preliminary material processing and forming stages. In so doing, pipe weld quality can be improved, reducing the risk that weld defects will propagate down the pipe mill and make it to the customer.

Topics: Tube and Pipe welding, submerged arc welding, weld seam alignment

Using Weld Cameras For Torch Alignment

Posted by Catherine Cline on Tuesday, August 16, 2016 @ 11:09 AM

When Xiris demonstrates its weld camera systems, one of the unexpected benefits an operator notices right away is the ability to quickly align the torch and seam.   Xiris weld cameras have integrated LED’s that provide a nice bright image of the seam and torch prior to starting the weld process.  Before we begin our demonstration, we ask the operator to align the torch and the seam which is usually done manually with a visual check.  Once we are told the system is aligned, we ask the operator to look at the computer screen and, 90% of the time, the torch and seam are misaligned.  The operator then begins to use the weld camera system right away to achieve perfect alignment on a consistent basis.

Here are three videos that demonstrate the alignment process.  In these examples the manufacturer has installed a positioning sensor on the robotic arm which is meant to ensure perfect torch alignment during each weld and the operator simply verifies the alignment prior to welding.

Operator Alignment:

The positioning sensor and the operator have misaligned the torch, resulting in a bad weld.

 

 

Weld Camera Assisted Alignment:

The operator has used the weld camera system to verify the alignment and you will see the adjustments that were made after the robot had been aligned.  Not only do the cameras ensure accuracy, the operator can perform the alignment quickly, right from the console rather than bending, stretching or climbing up on to the equipment to achieve proper alignment.

 

 

 

 

 

 

 

 

 

 

 

For more information on how Xiris Weld Cameras can ensure accurate alignment of your torch and weld seam, visit Xiris.com

Topics: quality control, weld camera, welding, High Dynamic Range, productivity, color weld camera, weld seam, weld seam alignment

Latest Posts

Follow Me