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Vertical-welding-tips:the Theory behind the Practice.SOLUTIONS with Effective, Powerful AdviceVertical-welding-tips are offered to the apprentice welder that has already mastered the basic welding skills. It is commonly accepted that an arc welder should have acquired during the training period sufficient skill in manipulating the electrode and in managing the weld pool in order to produce acceptable welds. The easiest position for welding is without doubt the flat one. It permits to achieve the highest deposition rate with adequate penetration. When making out of position welds some knowledge and experience with a few tricks of the trade should be applied for successful performance. In this page on Vertical-welding-tips we remind some basic facts and recommendations to develop the necessary skills, in order to weld in vertical position. Some of the knowledge refers to arc welding in general, other tips may be specific to welding with covered or flux cored electrodes. The right combination of technique selection and of acquired manual skill is needed for successful application of Vertical-welding-tips. The conscious welder should strive to improve the knowledge of the functions of the different materials composing the coverage or the core of shielded electrodes and of their influence on the behavior of the slag and the weld pool. Personal application and training will develop confidence in selection and use of suitable electrodes for applying successfully Vertical-welding-tips. A short explanation on the functions and types of flux covering for shielded electrodes used for Vertical-welding-tips can be found in the page on Slag inclusions at
The following sentence reported here from the above document is fundamental for essential understanding: "For vertical welding, the slag must be more fluid to flow out to the weld pool surface but have a higher surface tension to provide support to the weld pool and be fast freezing." Much depends on the ingredients, out of a list of about a dozen of them, which make up the slag produced by the electrode. The main tasks of the covering or core are to produce a shielding gas around the arc, to protect from contamination from the air, and to develop a suitable slag that insulates the weld bead to avoid oxidation at high temperature. Furthermore some of their characteristics are essential for making possible out-of-position welding as explained in Vertical-welding-tips. See the article "Filler Metal for Welding - Part two at Most common weld metal grades have been designed with various types of shielding. They offer a suitable variety of welding characteristics, with specific advantages in different welding positions. Some of these ingredients influence also the properties of the molten slag, like viscosity, surface tension and melting range. Therefore one should always select the electrode that is most suitable to perform the work at hand. "All positions electrodes", as sometimes advertised, is a misleading indication because one cannot optimize all the characteristic of the molten slag for whatever position including Vertical welding. In particular, for vertical welding one prefers to enhance certain properties of electrode covering, like fast freezing and a certain viscosity (to avoid too rapid dripping away) even at the cost of lower deposition rate than that attainable in flat position. Vertical down is done with electrodes having a cellulosic cover, which permits the use of high currents for welding at high travel speed. In general vertical down is used on thinner sheets, because it is considered less prone to burn through, as it provides for reduced penetration, and it is faster than vertical up. Skilled welders familiar with Vertical-welding-tips are said to prefer positioning thin sheets for vertical down welding even if the flat position is available, to increase welding speed and avoid burn through. Vertical up is used for thicker plates, the border being somewhere between 3 and 6 mm (1/8 to 1/4"). Using reverse polarity (direct current electrode positive) concentrates the heat on the tip of the electrode, leaving the work cooler. This is what one would want for out-of-position welding, because cooler work permits faster weld cooling, with less risk of drip off. A number of practical hints likely to be of substantial help to welders engaged in vertical welding, can be found in the following resources, available online. Stick Electrode Welding Guide - Lincoln (44 pages) available at A thorough treatise discussing the fine points of vertical welding and the differences to be taken into account when the progression is in the down direction as opposed to the up direction is presented with special emphasis to applications in pipeline constructions in a useful booklet by Lincoln Electric, called In the page on Fundamentals of Professional Welding, at
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