Fbe Anti-Corrosion Pipeline – Could It Get Far Better Than This..

We get lots of questions about welding pipe. Whether it’s about welding high-pressure pipe, Seamless Steel Pipe for food and beverage industries, or pipe for the oil and gas industries, there are a variety of common elements we see in pipe welding and fabrication which lead to problems. Such as from improper shielding gas and drive rolls to selecting a MIG gun with too low of an amperage rating. As companies push to train new welders, work with new materials, increase quality and productivity, and improve safety, you should focus on a few of these basic variables in the pipe welding process that could affect these efforts. In the following paragraphs, we’ll take a look at 13 of the most common issues we have seen in pipe welding applications and how to resolve them.

1. Forgetting to grind the joint after oxyfuel or plasma cutting

The oxyfuel and plasma cutting processes give a layer of oxide to the cut edge. This oxide layer must be removed just before welding, since the oxide often has a higher melting point compared to the base metal. After the arc gets hot enough to melt the oxide, it’s too hot for your base metal and can cause burnthrough. The oxides may also remain in the weld and cause porosity, inclusions, lack of fusion and other defects. It is important that welders be sure you grind the joint as a result of the parent material just before welding, along with grind the outside and inside diameters in the pipe to remove these oxides along with other potential contaminants.

2. Cutting corners with cutting

When welders work with materials prone to distortion as well as the affects of higher heat input, such as stainless steel and aluminum, a poor cut can lead to poor fit-up and create unnecessary gaps. Welders then compensate by putting more filler metal (thus, heat) in to the joint to fill it. This added heat can result in distortion and, with corrosion-resistant pipe like stainless-steel, can reduce the corrosion-resistant qualities from the base metal. It can also lead to absence of penetration or excessive penetration. Poor preparation also contributes to longer weld cycle times, higher consumable costs and potential repairs.

Shops currently using chop saws or band saws to slice pipe used in critical process piping applications should consider buying dedicated orbital pipe cutting equipment to make sure cuts within mere thousandths of an inch of the specified parameters. This precision helps ensure optimum fit-up and keeps the volume of filler and heat put in the joint at a minimum.

3. Forgetting to slice out and feather tacks

Tacking is essential to match-up, and finest practices suggest that the welder eliminate and feather that tack to be sure the consistency in the final weld. Specifically in shops where a fitter prepares the Carbon Steel Tube then someone else welds it, it’s essential that the welder knows just what is incorporated in the weld. Tacks left within the joint become consumed through the weld. When there is a defect inside the tack, or maybe the fitter used a bad filler metal to tack the joint, there exists a risk for defects inside the weld. Removing and feathering the tacks helps eliminate this potential problem.

4. Preparing a joint for MIG processes is different than with Stick welding

Training welders is actually a top priority for many fab shops, and – for better or worse – many welders bring past experiences together to the new job. These experiences may be addressed with adequate training, only one common mistake we see is welders with Stick experience not discovering how to properly create a joint for wire processes common in pipe fabrication applications. Welders trained traditionally in Stick and TIG welding often prepare the joint using a heavy landing area and want to keep your gap as narrow as you can. As pipe shops transition to easier, more productive MIG processes like Regulated Metal Deposition (RMD™), we prefer welders take that landing area down to a knife’s edge and space the joint at approximately 1/8-inch. This area is wider compared to those trained in Stick and TIG processes are employed to and can lead to a number of problems: focusing excessive heat to the edges in the weld, a lack of penetration and insufficient reinforcement on the inside the pipe. Shops should train their welders towards the specifics of each application and be sure they understand different weld preparation and operational techniques before they start working.

5. More shielding gas might not be better

Some welders use a misconception that “more shielding gas is better” and will crank the gas wide open, mistakenly believing these are providing more protection for the weld. This technique causes a number of problems: wasted shielding gas (resources and expense), increased and unnecessary agitation from the weld puddle, as well as a convection effect that sucks oxygen in to the weld and can result in porosity. Each station should be outfitted having a flow meter and every welder should discover how to set and follow the recommended flow rates.

6. Buy mixed gas – don’t depend on mixing with flow regulators

We have seen shops that, for any stainless application that requires 75/25 percent argon/helium, create another tank of argon along with a separate tank of helium and after that depend on flow regulators to bleed inside the proper quantity of shielding gas. The truth is you really don’t understand what you’re getting in a mix using this method. Buying cylinders of Ssaw Carbon Steel Spiral Welded Pipe from reliable sources, or buying a proper mixer, will ensure you understand exactly what you’re shielding your weld with and that you’re implementing proper weld procedures/qualifications.

7. Welding power sources don’t cause porosity

It is far from uncommon to obtain a call from the customer who says “Hey, I’m getting porosity out of your welder.” Plainly, welding power sources don’t cause porosity. We tell welders to recount their steps back from the stage where the porosity began. Welders will frequently realize that it began just each time a gas cylinder was changed (loose connections, incorrect gas used), a new wire spool was invest, when someone didn’t prep the material properly (oxides present in the weld), or maybe the fabric was contaminated someplace else over the line. Usually the problem is brought on by an interruption or downside to the gas flow. Tracing back your steps will usually lead dkmfgb the variable that caused the porosity.

Rise Steel consisted of subsidaries of Cangzhou Spiral Steel Pipe Factory, Hebei All Land Steel Pipe Factory, Hebei Yuancheng Steel Pipe Factory, Cangzhou Xinguang Thermal Insulation Pipe Factory .The company is located in Tianjin port, the largest comprehensive port and an important foreign trade port, engaging in the management of steel pipe production nearly 20 years.The company is a high-tech enterprise intigrated with independent production and sales business.We are committed to the concept of “innovation, technology and service”.

Rise Steel consisted of subsidaries of Cangzhou Spiral Steel Pipe Factory, Hebei All Land Steel Pipe Factory, Hebei Yuancheng Steel Pipe Factory, Cangzhou Xinguang Thermal Insulation Pipe Factory .The company is located in Tianjin port, the largest comprehensive port and an important foreign trade port, engaging in the management of steel pipe production nearly 20 years.The company is a high-tech enterprise intigrated with independent production and sales business.We are committed to the concept of “innovation, technology and service”.

Contact Us:
Address: APT. 1202 BLDG. B Kuang Shi Guo Ji Plaza, Tianjin Free Trading Testing Zone (Business Center), Tianjin, China.
Hamer Chen:[email protected]
Eason Gao: [email protected]
Miao lin: [email protected]
Amy Shi: [email protected]
Hamer Chen:+86 18202505824
Eason Gao: +86 18622403335
Miao lin: +86 13251845682
Amy Shi: +86 18630426996

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