We receive plenty of questions about welding pipe. Whether it’s about welding high-pressure pipe, Welded Thin Wall 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. Included in this are from improper shielding gas and drive rolls to picking 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, it is important to concentrate on some of these basic variables within the pipe welding process that can affect these efforts. In this post, we’ll take a look at 13 of the most common issues we have seen in pipe welding applications and the way to resolve them.

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

Both oxyfuel and plasma cutting processes add a layer of oxide for the cut edge. This oxide layer must be removed before welding, because 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 can also stay in the weld and cause porosity, inclusions, insufficient fusion and other defects. It is essential that welders remember to grind the joint as a result of the parent material before welding, as well as grind the in and out of diameters from the pipe to get rid of these oxides along with other potential contaminants.

2. Cutting corners with cutting

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

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

3. Forgetting to cut out and feather tacks

Tacking is critical to fit-up, and finest practices advise that the welder eliminate and feather that tack to be sure the consistency of the final weld. Particularly in shops when a fitter prepares the Seamless Steel Pipes and then somebody else welds it, it’s essential that the welder knows exactly what is within the weld. Tacks left in the joint become consumed through the weld. When there is a defect inside the tack, or if perhaps the fitter used a bad filler metal to tack the joint, there exists a risk for defects inside the weld. Cutting out and feathering the tacks helps eliminate this potential problem.

4. Preparing a joint for MIG processes is different compared to Stick welding

Training welders is actually a main priority for many fab shops, and – for better or worse – many welders bring past experiences along with them to the new job. These experiences could be addressed with adequate training, only one common mistake we percieve is welders with Stick experience not understanding how to correctly 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 would like to keep your gap as narrow as is possible. As pipe shops switch over to easier, more productive MIG processes such as 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 region is wider compared to those trained in Stick and TIG processes are utilized to and can lead to a number of problems: focusing too much heat to the edges in the weld, an absence of penetration and insufficient reinforcement on the inside the pipe. Shops should train their welders to the details of each application and make sure they understand different weld preparation and operational techniques before they start working.

5. More shielding gas might not be better

Some welders have a misconception that “more shielding gas is better” and can crank the gas wide open, mistakenly believing these are providing more protection for the weld. This method causes a number of problems: wasted shielding gas (resources and expense), increased and unnecessary agitation of the weld puddle, and a convection effect that sucks oxygen to the weld and can lead to porosity. Each station needs to 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 count on mixing with flow regulators

We now have seen shops that, to get a stainless steel application that needs 75/25 percent argon/helium, set up a different tank of argon along with a separate tank of helium then depend on flow regulators to bleed in the proper level of shielding gas. The reality is you truly don’t know what you’re getting in a mix with this method. Buying cylinders of Erw Structural Pipe from reliable sources, or purchasing a proper mixer, will guarantee you already know precisely what you’re shielding your weld with and this you’re adhering to proper weld procedures/qualifications.

7. Welding power sources don’t cause porosity

It is far from uncommon to obtain a call from a customer who says “Hey, I’m getting porosity from the 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 find that it began just whenever a gas cylinder was changed (loose connections, incorrect gas used), a whole new wire spool was devote, when someone didn’t prep the fabric properly (oxides present in the weld), or if the fabric was contaminated somewhere else across the line. Most of the time the thing is caused by an interruption or trouble with 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