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What are the effects of the electrode polarity on welding in the SAW process?
Think of Polarity as water flow in a pipe. Reverse Polarity means the flow is from the work to the machine. Straight Polarity is flow from the machine to the work. Heat is released when the flow tries to jump the gap. So in Reverse Polarity (where most SMAW is done) the heat builds up in the base metal which is usually thicker than the Electrode. The extra heat there helps melt the base metal. Straight polarity is usually employed when welding thin metals.
When current flows through a resistance is heat produced?
Yes, heat energy is produced by the electrons;however small it may be,actually if we consider a resistance then it is an hindered to the flow of electrons,as a result of which the electrons collide with the particles of wire resulting in loss of energy in the form of heat.the equation of heat generated is: H=(I^2 *R*t) where- H=heat produced in joules R=resistance of the material in ohm t=time of current flow in seconds
When to use dc welding machine and ac welding machine?
Dc welding can be used for non consumable electrodes with consumable electrode heat is transferred from electrode to work by molten metal. Ac welding is desirable for aluminum and magnesium, because it helps break up oxides AC is more stable than Dc.
When the bulb is the resistance what this tells about the resistance?
An incandescent bulb has a filament that has a resistance. The value of the resistance determines the current that will flow for a given supply voltage. The heat generated by the current flowing through the filament gives off light. As the resistance of the filament decreases the current increases and you get more light.
Why is heat transfer efficiency greater in arc welding processes that utilize consumable electrodes?
Because generally the tool used for arc generation (for example the tungsten electrode in GTAW) will absorb some of the heat.
The joining of metals by heat for making something structural or producing a continuous and permanent path for the flow of electric current is known as?
welding
In ultrasonic welding what creates the heat required for welding?
What creates the heat is the flame inside the torch
What is the difference between arc welding and resistance welding?
in arc welding only heat is used to weld metal. but in resistance welding pressure will also be used along with heat.
What are the effects of the electrode polarity on welding in the SAW process?
Think of Polarity as water flow in a pipe. Reverse Polarity means the flow is from the work to the machine. Straight Polarity is flow from the machine to the work. Heat is released when the flow tries to jump the gap. So in Reverse Polarity (where most SMAW is done) the heat builds up in the base metal which is usually thicker than the Electrode. The extra heat there helps melt the base metal. Straight polarity is usually employed when welding thin metals.
Can you use argon instead of oxygen with propylene?
No. Propylene is oxidised in presence of oxygen and the reaction is exothermic. The heat generated is used in welding. Argon is chemically inert and will not result in combustion.
What is the Different between TIG arc welding and gas welding?
Gas welding basically used for weaker joints(in sheets) and arc welding for stronger one(plates). mobile welding (not in a shop)is the ideal time for arc welding . gas welding is the way to go as far as production is concerned , but requires environment with little air circulation or wind , plus gas bottle , machine , and a short lead , which makes it ideal for shop work answer Gas welding - generally use for welding of thin plates/pipes. Less heat input and less likely to burn off the edge of the plates (undercut). It is a more expensive process because of gas shielding. Arc welding - use for thicker plates usually with larger size electrodes. Higher weld production rate. Shielding by means of electrode coating. Both processes can meet the required mechanical properties usually
What is the wasteful energy change that takes place in the wires of an electromagnet?
I believe it is the heat generated by the resistance of the wire to the flow of electricity that produces heat, which results in the loss of electromotive force, or electricity
What is the term tw refers to in welding?
TW = thermite welding, a welding process that requires no external source of heat or current.
What is used in welding?
A device that can generate heat. Melted material and the welding operation is performed.
What type of welding is when metal is fused together by the heat of a welding flame?
It's called Fusion Welding. You answered your own question.
What is resistance welding?
Arc. It's where electrical resistance is used to create the heat for the welding process.
How you calculate heat input and traveling speed for Gas Metal Arc Welding?
How you calculate heat input and traveling speed for Gas Metal Arc Welding?
