Know the Features and Benefits of Sub Arc Welding

Sub arc welding is a procedure where an arc is set up between the metal product and bare electrode. The dissolved weld pool and the arc zone comprising of the finish of the electrode tip are unseen and is intangible submerged under a coverlet granular fusible substance which is known as flux. In the process of sub arc welding, the copper coated electrode and bare metal work as fillers and dissolve with the welding method.  Granular flux is used which helps to secure the finished product from environment pollution. 

Sub Arc Welding

The heat is produced by the formation of an arc between the metal work piece and electrode which is contained under the flux. Flux becomes conductive when the dissolved pool is created, and existing path is trapped between the metal work piece and electrode. This flux also caters as a shelter to keep away from metal splashing. The method used in sub arc welding can be either automatic or semi-automatic. Welding tools generally will have feed drive rolls and DC Power source to supply the electrode constantly. The welding-gun includes the nozzle and the flux. 

Features of Sub Arc Welding process

Just like MIG welding, sub arc welding entails the creation of an arc among the metal work piece and a constantly-fed exposed wire electrode. This method makes use of a flux to create slag and protective gases. It also adds alloying rudiments to the weld pool. An additional protecting gas is not required at all. Before welding, a thin coating of flux-powder is put on the surface of the metal work piece. The arc passes through the joint row and as it does surplus flux is recycled through a hopper. The rest of the fused slag covers can be simply removed after the welding process. Since the arc is totally enclosed by the flux coating, the loss of heat in this process is very low. This generates a thermal competence as high as 60 percent. 

Benefits of Sub Arc Welding Process

Sub Arc Welding

• The exceptional quality of the weld.
• Uniform and smooth finished weld.
• No smoke and no splatter.
• High rate usage of electrode wire.
• No arc flash.
• No need to transform the electrode which saves welding time.
• Heavy segment welding in towering amps. 

Disadvantages of Sub Arc Welding

• Inadequate process for some particular metals.
• Usage is restricted to straight vessels, pipes and seams.
• Flux managing can be dangerous.
• Health concerns due to the flux.
• Slag exclusion required after welding. 

Process and Techniques of Sub Arc Welding

In general, we see that sub arc welding is superior to labor-intensive welding. In sub arc welding a huge liquefied pool of metal is created, and if the supply is bad, the slag and liquefied metal may overflow through the gaps spilling the weld. In case of manual welding the joint groundwork is not consistent, and if the substance doesn’t fit together equally, the worker has to structure these deviations by transforming the rate-of-advance or changing the electrode. A mechanical welding machine must be accustomed to making a suitable weld under a known set of terms, plus the apparatus will supply welding wire at the determined rate and speed of arc travel among the joint and the electrode. 

The union faces should be sparkling. It would be good to clean and line up the elements prior to welding. Inadequately cleaned mixture faces will create flaws of welding. The important factors in sub arc welding process are the welding speed, arc voltage, and arc welding current. These factors along with the depth of mix, the size and shape of the weld will ensure a high rate of production with the least use of power and electrodes.