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Correct current,travel speed, electrode angle, arc length
Bailee Jacobi
Wiki User
∙ 10y agoThere are two different issues here.
Slag is the easy one: If you weld with a process that uses a solid shielding material, like stick welding or flux-core wire feed, the slag is the residue from the shield. For slag-free welding, simply use a process that relies on a gaseous shield, like MIG. Otherwise, just pull out the ol' slag hammer and break the slag loose after welding.
Porosity has a lot of causes, and they all boil down to one thing: contamination of the weld puddle - either from the air (meaning your shielding has gone awry) or from some residue on the metal being welded. If you set your machine up right and weld only very clean material, your porosity problem should go away.
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What are the various procedures for visual examination of the welds for cracks porosity and slag inclusions?
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How would you avoid the occurrence of porosity or slag on weld?
Correct current,travel speed, electrode angle, arc length
How do you prevent the occurrence of slag inclusion and undercut?
The following techniques can be used to prevent slag inclusions: Use welding techniques to produce smooth weld beads and adequate inter-run fusion to avoid forming pockets to trap the slag. Use the correct current and travel speed to avoid undercutting the sidewall which will make the slag difficult to remove.
How do you explain welding defects and explain its testing?
Defects can be varied and classified as critical or non critical. Porosity (bubbles) in the weld are usually acceptable to a certain degree. Slag inclusions, undercut, and cracks are usually non acceptable. Some porosity, cracks, and slag inclusions are visible and may not need further inspection to require their removal. Small defects such as these can be verified by Liquid Penetrant Testing (Dye check). Slag inclusions and cracks just below the surface can be discovered by Magnetic Particle Inspection. Deeper defects can be checked thru X-raying.
How does arc length affect a weld?
Too long an arc length allows the arc to wander creating a poorly shaped weld. The slag is usually too thin and can allow Oxygen in the air to attack the molten puddle which causes Porosity in the weld. Too short an arc length buries the slag and creates less heat which traps the slag and impurities. Keep in mind that electrode coatings help determine the correct arc length.
What are the welding defects in sheet metal?
Porosity is the most common weld defect. For beginners don't rule out lack of penetration and non-compatible welding rod or filler wire. It all depends on how the weld failed if it has. Proper prep and preheat is required in many types of welding. So a little more detailed question can help me give you a more detailed answer. Trapped slag is also a common problem. It creates a void in the weld. Although porosity is the most common defect some porosity doesn't necessarily affect the weld strength.
What is remedy to prevent slag inclusions?
Remedies to prevent slag inclusions - Avoid atmospheric contamination using proper welding procedure e.g. adequate Shielding Gas Proper removal of slag from weld bead surface using wire brush Redesigning the weld joint to permit sufficient space for manipulation of the puddle of molten weld material
Is coke used to oxidise slag?
Coke is not used to oxidize the slag . It is carbon that is used to oxidize slag.
What is slag called in Australia?
its still called slag
What files and software you would need to set up an It system?
suck out you slag
What can slag be used for?
waste slag from blast furnaces is used for road surfacing.
What is slag hammer?
It is a hammer with a flat broad head for knocking slag off.
