What is submerged arc welding process?

What is submerged arc welding process?

Submerged Arc Welding (SAW) is a joining process that involves the formation of an electric arc between a continuously fed electrode and the workpiece to be welded. A blanket of powdered flux surrounds and covers the arc and, when molten, provides electrical conduction between the metal to be joined and the electrode.

Why submerged arc welding is used?

Submerged arc welding is used to weld low- and medium-carbon steels, low-alloy high-strength steels, quenched and tempered steels, and many stainless steels. Experimentally, it has been used to weld certain copper alloys, nickel alloys, and even uranium. Metal thicknesses from 1/16 to 1/2 in.

What type of welding is submerged arc welding?

Submerged-arc welding (SAW) is a common arc welding process that involves the formation of an arc between a continuously fed electrode and the workpiece. A blanket of powdered flux generates a protective gas shield and a slag (and may also be used to add alloying elements to the weld pool) which protects the weld zone.

What is the difference between arc welding and submerged arc welding?

The difference between submerged arc welding and regular arc welding is that the welding wire, arc, and weld joint are covered by a layer of flux. The flux creates a pathway for the arc to travel through to the material that is being welded.

Which type of electrode is used in submerged arc?

The submerged arc welding process uses either direct or alternating current, but the direct current is used for most of the applications. Both direct current electrode positive (DCEP) and direct current electrode negative (DCEN) are used.

What is the difference between DCEN and DCEP?

The DCEN mode is often used on open root runs to reduce the risk of burn-through, whereas DCEP is used to reduce the risk of lack of fusion defects. DCEN can also be used for surfacing applications in order to minimise penetration, and thin sheet welding.

What are the advantages and disadvantages of submerged arc welding process?

Submerged Arc Welding is ideal for parts that require a long straight weld bead. It has advantages such as: High quality of the welding process; Torch travel speed can be quite high (compared to processes like MIG/MAG or TIG welding);

What are the disadvantages of submerged arc welding?

Limitations

• Not very portable.
• Process may be limited to flat or horizontal-fillet welding positions.
• Limited to steel/stainless steel, and some nickel-based alloys.
• Best for long straight seams or rotated pipes or vessels.
• Requires flux handling systems.
• Requires post weld slag removal.
• Best for thicker materials.

What type of welding is GTAW?

Tungsten Inert Gas (TIG) welding, also known as Gas Tungsten Arc Welding (GTAW) is an arc welding process that produces the weld with a non-consumable tungsten electrode. Tungsten inert gas (TIG) welding became an overnight success in the 1940s for joining magnesium and aluminium.

What is Dcsp and Dcrp in welding?

Direct Current Straight Polarity (DCSP) Direct Current Reverse Polarity (DCRP) When an electrode is connected to the negative (-ve) terminal of the power supply i.e electrode behaves as a cathode then the connection is known as DCSP.

What is another name for DCEP?

Direct current electrode positive (DCEP) is what we used to call reverse polarity. Direct current electrode negative (DCEN) is what we used to call straight polarity.

What is the biggest disadvantage of submerged arc welding?

Some of the limitations/disadvantages of submerged arc welding are:

• Due to the large weld pool, the weld has to be done in a horizontal position;
• The process requires more training from its operators given greater complexity and control of the process;

Why the quality of submerged arc welding is very good?

Because of the excellent protection of the weld metal by the blanket of molten slag, SAW can produce high-quality welds with fewer weld defects than other processes.

What is the difference between GTAW and GMAW?

In gas metal arc welding (GMAW), the electrode is consumable type as it melts down due to arc heating and subsequently deposits on weld bead. Contrary to this, in gas tungsten arc welding process (GTAW) process, electrode remains intact under intense arc heating.

What is GTAW and SMAW welding?

SMAW and GTAW are common arc welding processes in which heat required to melt parent and filler material is generated by an arc established between an electrode and the workpiece.

What is the difference between Dcsp and Dcrp in arc welding?

Distortion is less with DCRP and also HAZ is narrow. DCSP is not suitable for welding thin plates. DCSP is suitable for welding thin plates. Metals with high melting temperature (such as stainless steel, titanium) can be suitably joined by DCSP.

Which is better DCEP or DCEN?

In general, operating on DCEP results in greater penetration, and DCEN results in reduced penetration and a reduction in dilution of the weld metal with the substrate. This is important for electrodes that are capable of being used on both DC polarities (and AC).

What is DCEN and DCEP?

What are the advantages and disadvantages of submerged arc welding?

Advantages of Submerged Arc Welding

• Strong, sound welds are readily made.
• Minimal welding fume is emitted.
• Minimal arc light is emitted.
• SAW is suitable for both indoor and outdoor works.
• Less distortion.
• Deep weld penetration.
• Minimal edge preparation.
• High deposition rates are possible.

Is submerged arc welding the right process for You?

The submerged arc welding (SAW) process has the potential to substantially improve deposition rates and productivity, and to provide repeatable weld quality. However, it is better suited for some applications than others. When considering SAW, there are numerous factors that can affect process success.

Which is better, arc welding or MIG welding?

MIG welds are known to be more pleasing to the eye and would not require a lot of touch-ups. This will be highly different from arc welds that will require a lot of cleanups before they can look presentable. Arc welding will usually have a lot more sparks and debris which can make the welds not very appealing.

What are the common welding defects in arc welding?

Undercut

How does submerged arc welding work?

Pressure Vessels. Since SAW with the proper parameters can produce high-quality welds,it can be ideal for things such as gas tanks.