Why and How Oxygen Destroys Your Welding - Essay Example

Why and How Oxygen Destroys Your Welding Student’s name Affiliation Date Why and How Oxygen Destroys Your Welding Introduction Oxygen welding also termed as oxy-fuel gas welding involves the use of oxygen and other flammable liquids under pressure. It is highly used in industries and oxy-fuel is among the oldest forms of welding where oxygen is applicable. Oxygen welding is ideally suited for repair welding and for welding thin sheets, tubes and small diameter pipes. In oxy welding, oxygen is not usually the fuel but a combining agent to the fuel that produces the welding heat in a process known as oxidation. The oxidation process works in presence of pure oxygen gas as the catalyzing agent to the process. Oxygen emanates from the normal air under pressure by passing through certain chemical processes. The gas is then stored in special gas cylinders that hold it for commercial processes especially welding process (Folkhard, 2012). The welding process involves heating of the metal joints to their melting point by the flame torch formed by the oxidizing gas. The molten metal formed with the effect of heating cools leaving solid seamless joints that holds the joints together. In this case, there are factors that relatively put oxygen a limiting ingredient in the oxy-fuel welding world as discussed in the following sections. Upon using a moderate or neutral flame on steel surfaces, the metal does experience neither, boiling foaming nor high rate of sparking. This is because the steel metals experiences a low late of melting and a low pressure of the oxidizing agent (oxygen) and therefore an equivalent natural cooling process. The initial metal remains calm and clean an experience that hinders oxidation of the molten steel forming a tough joint that is precisely a hard and tough joint that would be difficult to mend or make repairs in case of a default in or in making an adjustment (Li, Ma& Li,2010). The difference in flame quality and strength gives a very diverse experience. Considering the strong carburizing frame populated by a lot of oxygen gas in the mixer to form an oxidizing flame. Usually, the strong flame adds carbon to the molten steel causing brittleness to the product. The excessive strong heat causes the molten steel to spark and foam and or puddle indicating the formation of an iron oxide that will later cause a porous weld. The excess oxygen in the flame will always change the welding environment into an oxidation process that leads to porousness in the weld (Roepke et al, 2010). The welding process is common and highly used in low-carbon steel metals and a low alloy steel of which is prone to environmental impurities that is hindrance. Considering the submerged arc welding, the oxygen effects are vivid during the negative temperature testing. This is whereby the absolute zero temperature is under test during normal conditions. Despite the fact that there are differences in the weld strength, it has attributes of environmental standards of impurities and presenting the reacting agents. The amount of oxygen is the most critical substance to concentrate upon in the welding flame. There are many known and used active gases and electrodes such as petrol, Low hydrogen-potassium, low hydrogen-iron powder, Iron oxide-sodium, Iron-oxide-iron powder, cellulose potassium among many others. The oxygen content in the flame (torch) determines the strength and the brittleness of the metal. Research done in calculating the proportions of the oxide capacity in the oxidation process have clearly shown that the increase of oxygen does not certainly in result in change of the ferrite grain bond in the metal alloy(Sathiya et al,2012). The increase of the welded metal forces through content in order to brittle fracture due to increase of oxygen content that may condition by a microscopic slag. The inclusion of the microscopic slag in the bonding boundaries known as the grain boundaries promotes crack initiation in deformed metal and oxides inclusions in ferrite that soon or later serve as stress concentrators. Such experience is common especially with the learners in their early stages of experience of conditioning the properties and the ingredients. When the metal bridge experiences stress at this stage of overloading, the oxide normally acts as a point of crack propagation. The other factor not only considers the metallic oxide inclusion but also the shape of the metal. This normally influences the toughness and plasticity of the metal. Irregular and angular shapes are always because of the high melting conditions that exhibit the metal to any kind of irregularity as the molten metal cannot cool in a uniform style. This is highly associated with alumino-solicates in the process of applying of an external load. The irregularities in shape and angular shapes form and act as stress areas to the metal. However , the fact that it is not the oxide inclusion that produces the major effect, the amount of alloy and the amount of the dead still caused by the excessive heat. This condition is controllable and solved by using an additional strengthening various alloys. Free silicon is one of the alloys used in low-alloy steels under silicon-containing fluxes. The effect provides a minimal silicon usage environment in the welding pool. The result of the metal oxygen content from the welding wire happens to reduce the brittleness of the metal more preferably than the killed steel welding wire (Yan, Gao & Zeng, 2010). Research to determine the relationship of oxygen content in different conditions of the supplements explains the above problems in a more open and a better scenario to make a reliable conclusion. The experiment involves a gradual assessment of the effect of oxygen and silicon content on the weld metals and the non-metallic alloy on the inclusion on the bases of brittleness fracture. The results gives another interesting scenario whereby a conclusion is made from the observations that in any addition of 0.1% of oxygen leads to a demand of 2.5 times the content of oxygen which is a big bridge in the as compared to the amount of silicon alloy (Folkhard, 2012). Normally, these kinds of tests are considerably very intensive, as many samples have to be present in the exercise. In the calculation of the susceptibility of a material to brittle stress intensity, a factor defined by the crack profile is the most critical measure in this experiment as it is simply the oxidation catalyst to the welding content. On the other hand, the brittle factor that the material poses stands out to be an important factor to keep in mind as the effect experienced has relationship with the effects of the material or the metal under operation. The experiment shows a good and preferable scenario that explains the above assumptions fully. It is absolute that the effect of oxygen to the toughness of the metal has close relationship with the characteristics of other additional factors whereby the decrease in the oxygen content increases the toughness. The experiment also shows that the plasticity of the metal also lowers in a large factor while the oxygen content decreases to less than precisely 0.02%. This is ultimately the result of lowered melting points and therefore unexpectedly enhancing the formation of sulfides, silicates and oxy sulfides. This promotes precipitation whereby oxides and carbide particles ends up deposited because of the melting of sulfur. The welding pool experiences other additional materials as far as porousness maybe observed (Li, Ma, T & Li, 2010). The tests assert that 0.2% – 0.035% is the standard oxygen content as far as the material under welding. The brittleness and the fracture strength depend on the metal-based oxides inclusion content than the alloy itself. In this case, the precipitation is an added advantage to the strength of the metal. It is only in the welding scenario whereby the oxygen content is at the range of 0.035% and the effect of precipitation is evident. Although this is a microscopic process, the microscopic oxides precipitate which are partially located along the grain boundaries block the dislocations and serve as the crack nuclei giving a strong feel (Li, Ma, T. & Li, 2010). During welding overheating is a common phenomenon whereby power surge is evident. Use of inappropriate power carrying cables and poor adjustments of the welding machine is the common error identified. Under normal circumstances, Overheating causes a number of negative factors to both the metal and the user. First, an overheated metal joint will always be a loss to the user or the principle person involved. The fact that the high intensity flame may cause even a bigger crack than it was there before or even dislocates an unintended joint. This is misconduct or poor work and an injustice to the owner (Folkhard, 2012). An overheated metal also does not maintain its normal texture and therefore the act degrades its corrosion resistance and its other mechanical properties as well. This may leave the metal in a condition that minimizes or disregards its function to the purpose initially intended making it useless. The other factor is vivid to the eye and can be spotted from a distance unless there is another coating involved. The color of an overheated metal piece changes levels of black and blue, this is because of the high temperature that reacts depositing the product color on the sides of the metal. This place becomes porous and can well react with the air outside forming rust and with time, the metal wares out reducing its life span (Sathiya et al, 2012). Conclusion It is paramount to put in mind the type of the material under welding. It is so unfortunate that the errors in welding are hardly undone and therefore require keen handling and precautions to deter the mistakes that may arise through negligence. To reduce overheating, we should consider reducing the amperage, increasing the traveling speed or shortening the arc length. References Folkhard, E. (2012). Welding metallurgy of stainless steels. Springer Science & Business Media. Li, W. Y., Ma, T., & Li, J. (2010). Numerical simulation of linear friction welding of titanium alloy: effects of processing parameters. Materials & Design, 31(3), 1497-1507. Roepke, C., Liu, S., Kelly, S., & Martukanitz, R. (2010). Hybrid laser arc welding process evaluation on DH36 and EH36 steel. Welding journal, 89(7), 140-149. Sathiya, P., Mishra, M. K., & Shanmugarajan, B. (2012). Effect of shielding gases on and mechanical properties of super austenitic stainless steel by hybrid welding. Materials & Design, 33, 203-212. Yan, J., Gao, M., & Zeng, X. (2010). Study on microstructure and mechanical properties of 304 stainless steel joints by TIG, laser and laser-TIG hybrid welding. Optics and Lasers in Engineering, 48(4), 512-517. Read More