Welded Pipe Fittings – Stop By Our Site Now To Look For Further Resources..

We get plenty of questions about welding pipe. Whether it’s about welding high-pressure pipe, Erw Black 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 anything from improper shielding gas and drive rolls to choosing 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 give attention to a few of these basic variables within the pipe welding process that can impact these efforts. In the following paragraphs, we’ll look at 13 of the most common issues we see in pipe welding applications and how to resolve them.

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

Both oxyfuel and plasma cutting processes give a layer of oxide for the cut edge. This oxide layer has to be removed just before welding, since the oxide often includes a higher melting point compared to base metal. When the arc gets hot enough to melt the oxide, it’s too hot for the base metal and can lead to burnthrough. The oxides may also remain in the weld and cause porosity, inclusions, insufficient fusion as well as other defects. It is crucial that welders remember to grind the joint right down to the parent material before welding, in addition to grind the outside and inside diameters of the pipe to get rid of these oxides and other potential contaminants.

2. Cutting corners with cutting

When welders assist materials very likely to distortion and also the affects of higher heat input, including stainless steel and aluminum, a bad cut can cause poor fit-up and produce 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, is able to reduce the corrosion-resistant qualities from the base metal. It can also cause insufficient penetration or excessive penetration. Poor preparation also results in longer weld cycle times, higher consumable costs and potential repairs.

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

3. Forgetting to cut out and feather tacks

Tacking is critical to match-up, and best practices recommend that the welder reduce and feather that tack to be sure the consistency of the final weld. Specifically in shops when a fitter prepares the Lsaw Pipe then someone else welds it, it’s important that the welder knows exactly what is within the weld. Tacks left within the joint become consumed through the weld. When there is a defect within the tack, or if perhaps the fitter used the incorrect filler metal to tack the joint, you will find a risk for defects within the weld. Cutting out and feathering the tacks helps eliminate this potential problem.

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

Training welders is a top priority for many fab shops, and – for better or worse – many welders bring past experiences together to the new job. These experiences could be addressed with adequate training, but 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 wish to keep your gap as narrow as is possible. As pipe shops switch over to easier, more productive MIG processes like Regulated Metal Deposition (RMD™), we prefer welders take that landing area right down to a knife’s edge and space the joint at approximately 1/8-inch. This place is wider than those trained in Stick and TIG processes are used to and can cause numerous problems: focusing excessive heat in to the edges of the weld, an absence of penetration and insufficient reinforcement on the inside of the pipe. Shops should train their welders towards the specifics 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 possess a misconception that “more shielding gas is better” and can crank the gas wide open, mistakenly believing they may be providing more protection for the weld. This method causes several problems: wasted shielding gas (resources and expense), increased and unnecessary agitation in the weld puddle, and a convection effect that sucks oxygen in to the weld and can lead to porosity. Each station ought to be outfitted using a flow meter and every welder should understand how to set and follow the recommended flow rates.

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

We have seen shops that, to get a stainless steel application that will require 75/25 percent argon/helium, setup a separate tank of argon as well as a separate tank of helium and after that depend on flow regulators to bleed in the proper quantity of shielding gas. The truth is you actually don’t know what you’re getting in a mix using this method. Buying cylinders of 40mm Galvanised Steel Pipe from reliable sources, or buying a proper mixer, will ensure you already know precisely what you’re shielding your weld with and this you’re implementing proper weld procedures/qualifications.

7. Welding power sources don’t cause porosity

It is really not uncommon to get a call coming from a customer who says “Hey, I’m getting porosity from your welder.” Plainly, welding power sources don’t cause porosity. We tell welders to recount their steps back from the point where the porosity began. Welders will often find that it began just whenever a gas cylinder was changed (loose connections, incorrect gas used), a brand new wire spool was put in, when someone didn’t prep the material properly (oxides found in the weld), or if the content was contaminated someplace else along the line. More often than not the issue is due to an interruption or trouble with the gas flow. Tracing back your steps will often 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:sales0@rise-steel.com
Eason Gao: sales1@rise-steel.com
Miao lin: sales2@rise-steel.com
Amy Shi: sales5@rise-steel.com
Hamer Chen:+86 18202505824
Eason Gao: +86 18622403335
Miao lin: +86 13251845682
Amy Shi: +86 18630426996

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