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| SMAW |
SMAW WELDING
SMAW welding is a technique by using an electric current flows and electrode arc-shaped webbed. Other types of arc welding with an electric current is submerged arc welding SAW, gas metal arc welding GMAW-MIG, gas tungsten arc welding and plasmaarc G. In SMAW welding gas occurs when the electrode terselaput penyelimut it melts, so the process is not required pressure / pressure inert gas to displace the oxygen or air can cause corrosion or bubbles in the weld-weld. Prose welding occurs because the electric current flowing between the electrodes and welding material forming the heat so it can reach 3000 ° C, thus making the electrode and the material to be welded to melt. Based on its current type, welding is divided into AC and DC current, which distinguished DC Straight polarity-polarity of the direct and reverse polarity - polarity reversed. Welding machine is being divided into two types, namely constant current - constant voltage and current fixed - fixed voltage, dimanapada any arc welding electrical current in case of an enlarged bow will lower and raise the voltage and current in a shortened arc will improve the flow and lowering the voltage.
To get a good weld should:
- using appropriate electrodes
- appropriate type of current
- polarity type is right for DC current
- avoid welding the left-right movement during welding
- short form of the arc current, welding do a steady and orderly
- the rate of welding electrodes in accordance with the speed of the melt.
The problems that often arise in the arc welding current is:
- electrode freezes / stops welding
- form an ugly seam welding
- arc welding current is bad because it expands
- Moderate membrane electrode / flux is generally made dariserat
- wood / cellulose
- titanium oxide
- + titanium base compound
- Mn + Fe + Si
- Iron oxide
- CaCO3, which will form jebnis-type electrode in the form type: E, R, ER, EC, EW, B, RB, RG and F.
Selection of electrodes is based on:
- properties of the materials to be welded
- welding position
- connection type
- number of welding
- density welding connection
- type of current available.
