Term
| How are metallic parts fused in the flux cored arc welding process? |
|
Definition
| Metallic parts are fused by heating them with an arc between a continuously fed, consumable, flux cored electrode and the work. |
|
|
Term
| Where are the fluxing ingredients for the primary shielding of the FCAW process located? |
|
Definition
With-in the metal tubular electrode, they are deposited as slag on top of the weld.
Flux CORED arc welding. Flux is located in the core. |
|
|
Term
| What are the two processes used for deposition of molten material in FCAW? |
|
Definition
The open arc process (FCAW-ss)and
The gas shielded arc process (FCAW-g) |
|
|
Term
| What gases may be used in the FCAW-g process? |
|
Definition
| Carbon Dioxide is used alone, or in combination with argon in a specified mixture of the two gases. C25 for example. |
|
|
Term
| When the welder deposits the weld metal using a hand-held gun, the operation is called ________. |
|
Definition
|
|
Term
| When a welding operator uses specialized equipment and monitors the process, the operation is called _______. |
|
Definition
|
|
Term
| What are the two types of supply current used in FCAW? |
|
Definition
Direct Current Electrode Negative (DCEN)
Direct Current Electrode Positive (DCEP) |
|
|
Term
| The two types of power supplies used in the FCAW process are constant ______ and constant _______. |
|
Definition
Constant Voltage (CV) the power supply unit is generally used for FCAW.
Constant Current (CC) unit may be used with a different type of wire feeder. |
|
|
Term
| An electromechanical device that feeds the required amount of filler material at a fixed rate of speed is called a(n) ______. |
|
Definition
|
|
Term
| Insufficient gas coverage will cause the weld wire and molten metal to ______, diminishing the metal's strength. |
|
Definition
|
|
Term
|
Definition
|
|
Term
| Name the advantages of FCAW. |
|
Definition
Very Good Depostion.
No stub loss.
All position.
Flux can not be broken off because it is inside the wire. |
|
|
Term
| What are the main disadvantage of FCAW? |
|
Definition
|
|
Term
| What is the purpose of a shielding gas? |
|
Definition
| To protect the weld from the atmosphere, stabilize the arc, cleans the joint, and aids metal deposition and heat transfer. |
|
|
Term
| What is the purpose of purging when welding? |
|
Definition
| Force out the atmosphere from the back of a weld joint and protect from oxidation. |
|
|
Term
| What is the purpose of purging when changing the bottle of gas? |
|
Definition
| To clear the lines of any contaminates and oxygen. |
|
|
Term
| Flowmeters measured in what? |
|
Definition
|
|
Term
| What are pressure gauges measured in? |
|
Definition
|
|
Term
| How do you test for gas leaks? |
|
Definition
| Spray the joints with soapy water and make sure there is no bubbles present. Also, the drop test. Close the bottle and see if the meter drops. |
|
|
Term
| What is the main criteria that must be observed before you weld? |
|
Definition
| Base joint and joint types. Filler materials. Current type and polarity. Shielding gas as directed by WPS or welding manufacturer. Electrode Stick Out (ESO) |
|
|
Term
| What technique is used when welding with the FCAW process is it drag or push? |
|
Definition
|
|
Term
| Why are weave beads not recommended for FCAW? |
|
Definition
| Distortion, to much heat input, possible slag inclusions, and possible undercut. |
|
|
Term
| What are the side effects of a bad ground? |
|
Definition
| Arc outages.Poor Weld quality. |
|
|
Term
| Why do we always run a test weld? |
|
Definition
| To make sure welding parameters and variable are set right. |
|
|
Term
| You're welding and you see undercut in the weld, how do you correct it? |
|
Definition
| Correct your angle and speed. If oscillating remember to pause and dwell on each side of the weld. |
|
|
Term
| What does E71T stand for? |
|
Definition
| E - Electrode, 7 is 70,000 psi tensile , 1 is for all positions, T is for tubular electrode. |
|
|
Term
| Where do you find the welding parameters and variable for any consumable electrode? |
|
Definition
| Refer to the wire manufacturer. Also, you can look it up on the internet. |
|
|
Term
| Name the three types of wire feeders? |
|
Definition
| Push, pull type, push-pull type. |
|
|
Term
| What directs the shielding gas to the weld area? |
|
Definition
|
|
Term
| How should gas cylinders be properly stored? |
|
Definition
| Up right with the cap on and secured to a solid structure. |
|
|
Term
| What is observed when welding with Carbon dioxide only? |
|
Definition
| Globular mode of deposition and spatter. |
|
|
Term
| What complications can be formed when welding over oxides or contaminated metal? |
|
Definition
| Weld defects such as porosity can be formed. |
|
|
Term
| You are welding with gas shielded flux core and you have to change to Intershield flux cored wire, run through the procedures to make this happen? |
|
Definition
| Turn off your gas. Change to a proper flux core whip. Change drive rollers and contact tip. Change the polarity from DCEP to DCEN. Run test welds. |
|
|
Term
| You are preparing metal for FCAW or GMAW welding. Describe the best cleaning procedures for sound welding. |
|
Definition
| Hit it with a torch to burn off oil, if any. Descale the metal and if possible use a alcohol based cleaner. |
|
|
Term
|
Definition
| Electrode with 70,000 tensile strength, Solid electrode, 6 is alloy composition. |
|
|
Term
| You are welding with FCAW or GMAW and you suddenly notice porosity in your welds. Describe the process of elimination to find the source of the porosity. |
|
Definition
| Check the source of the gas. Make sure your work piece is cleaned properly. Make sure there is no drafts or high winds by putting up shields. Check all the gas lines and hoses. Make sure your wire is stored properly away from contaminates. Leaks in the whip. |
|
|
Term
| If you can not find a suitable ground location, how would you overcome it? |
|
Definition
| Weld a removable ground tab. |
|
|
Term
| What is the purpose of preheating? |
|
Definition
| Bring the metal up to a working temperature and remove moisture and contaminates. |
|
|
Term
| What is the purpose of checking interpass temperatures when doing multi pass welds? |
|
Definition
| To Control the distortion and stop the metal burn through and blow out of filler material. |
|
|
Term
| Name the drive rolls for hard wire, flux core, and aluminum? |
|
Definition
| V groove for hard wire, Knurled groove for flux core, U groove for aluminum. |
|
|
Term
| What changes would you make to the wire feeder if you had to change the size of the wire |
|
Definition
| Drive rollers, contact tip, liner. |
|
|
Term
| Name the three types of metal deposition modes in GMAW. |
|
Definition
| Short Circuit, Globular, and spray. |
|
|
Term
| List the main advantages of GMAW. |
|
Definition
| High quality welds, usable in all positions, no slag, and highly efficient. Also can be used to bridge large gaps. Easy to learn. |
|
|
Term
| You are about to weld on zinc coated metal. What procedures should you follow? |
|
Definition
| Respirator, ventilation, clean down to bare metal as much as possible. |
|
|
Term
| Your about to weld on a metal you are unsure of. What procedure should you follow? |
|
Definition
| Determine if it is ferrous or Non ferrous by use of a magnet. Select the appropriate filler material. Refer to the WPS. |
|
|
Term
| Explain duty cycle and how it is measured. |
|
Definition
| Duty cycle is how long a machine can run at max capacity in a ten minute period. |
|
|
Term
| What procedure would you follow if you have a birds nest? |
|
Definition
| Select the correct break roll tension and drive roll tension. |
|
|
Term
| What effects does short ESO have on penetration? What effect does a long ESO have on penetration? |
|
Definition
| Short ESO increases the penetration and Long ESO decreases penetration. |
|
|
Term
| Name the characteristics of Aluminum. |
|
Definition
| Excellent Thermal and Electrical conductivity. Good Strength to weight ratio. Light Weight, low density. corrosion resistant. |
|
|
Term
| What gases are used in aluminum welding? |
|
Definition
| Pure Argon and Helium or a Argon helium mix. |
|
|
Term
| Whats the melting point of aluminum? |
|
Definition
|
|
Term
| What are the procedures of cleaning aluminum before welding? |
|
Definition
| Clean it with acetone cleaner, Use a stainless steel wire brush to break off the oxidation. |
|
|
Term
| What color does aluminum change when heated? |
|
Definition
|
|
Term
| Whats the main alloy in 5 series aluminum and what effect does it have on the metal. |
|
Definition
| Magnesium. Strengthens the metal and helps resist corrosion. |
|
|
Term
| How do you avoid craters at the end of the weld? |
|
Definition
| Use a run off tab at the end of the weld or Crater fill techniques. |
|
|
Term
| Do you push or pull during aluminum welding and why? |
|
Definition
| Push because it helps to clean as you are welding into it. |
|
|
Term
| Name the two most common types of guns used in aluminum welding. |
|
Definition
| Push-pull and spool guns. |
|
|
Term
| Why is it important to remove the oxide layer on aluminum? |
|
Definition
| The oxide layer melts at a higher temperature then alumium. Melts at 3600F and can hold moisture that leads to weld discontinuities. |
|
|
Term
| What is the main current used to aluminum welding? |
|
Definition
|
|
Term
When the welding process involves the electrode contacting the work piece, what is this called?
When the welding process involves dropping the electrode to the work piece in a fine mist, what is this called? |
|
Definition
| Short-circuit mode. Spray mode. |
|
|
Term
| What is the purpose of a welding log? |
|
Definition
| To record welding data for quick reference. |
|
|
Term
| What is the procedure for successful multi pass welding? |
|
Definition
| Clean between each weld and monitor your inter pass temperature. |
|
|
Term
|
Definition
|
|
