OXY-ACETYLENE GAS WELDING AND ITS PROCESS

Oxy-acetylene gas welding is accomplished by the melting edges or surface to be joined by gas flame and allowing the molten metal to flow together, thus forming a solid continuous joint upon cooling. This process is particularly suitable for joining metal sheets and plates having thickness of 2 to 50 mm. With material thicker than 15 mm, additional metal called filler metal is added to the weld in the form of welding rod. The composition of the filler rod is usually the same or nearly the same as that of the part being welded. To remove the impurities and oxides present on the surfaces of the metal to be joined and to obtain a satisfactory bond a flux is always employed during the welding except mild steel which has more manganese and silicon that act as a de-oxidizing agents.

Various gas combinations can be used for producing a hot flame for welding metals. Common mixture of gases is oxygen and acetylene, oxygen and hydrogen, oxygen and other fuel gas, and air and acetylene.

The oxygen acetylene mixture is used to a much greater extent than the other and has a prominent space in the welding industry.

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Mechinopedia For Mechanical Engineers

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