Term
| 2. What is a combination welding-cutting torch? |
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Definition
| A torch handle that can have different attachments such as a cutting head or welding tip attached. |
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Term
| 3. State one advantage of owngin a combination welding-cutting torch as opposed to just having a cutting torch. |
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Definition
| The combination torch offers more flexability than the dedicated cutting torch. |
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Term
| 4. State one advantage of owning a dedicated cutting torch as compared to having a combination welding-cutting torch. |
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Definition
| The dedicated cutting torches are usually longer and have larger gas flow passages than the combination torches. The added length of the dedicated cutting torch helps keep the operator further away from the heat and sparks and allows thicker material to be cut. |
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Term
| 5. What is a mixingt chamber? Where is it located? |
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Definition
| It is one method used to mix oxygen with the fuel gas. It may be located in the torch body or in the tip. |
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Term
| 6. Define the term equal-pressure torch. How does it work? |
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Definition
| It's a type of torch mixing that requires both gases to enter the mixing chamber under the same pressure. The mixing chamber is larger than both the gas inlet and gas outlet. This larger size causes turbulence in the gases, resulting in the gases being mixed thoroughly. |
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Term
| 7. How does an injector-type mixing chamber work? |
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Definition
| The injector works by passing oxygen through a venturi, which creates a low-pressure area that pulls the fuel gases in and mixes them together. |
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Term
| 8. State the advantages of having two oxygen regulators on a machine-cutting torch. |
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Definition
| The addition of a separage cutting oxygen supply allows the flame to be more accurately adjusted. It also allows the pressures to be adjusted during a cut without disturbing the other parts of the flame. |
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Term
| 9. Why are some copper alloy cutting tips chrome plated? |
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Definition
| The chrome plating prevents spatter from sticking to the tip and that prolongs the tips usefulness. |
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Term
| 10. What determines the amount of preheat flame requirements of a torch? |
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Definition
| The type of fuel gas used and by the material thickness, shape, and surface condition. |
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Term
| 11. What can happen if acetylene is used on a tip designed to be used with propane or other such gas? |
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Definition
| The tip may overheat, backfire, or explode. |
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Term
| 12. Why are some propane and natural gas tips made with a deep, recessed center? |
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Definition
| The flame burns at such a slow rate that it may not stay lit on any other tip. |
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Term
| 13. What types of tip seals are used with cutting torch tips? |
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Definition
| Some cutting tips have metal-to-metal seals, and other cutting tips have fiber packing seats to the the tip to the torch. |
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Term
| 14. If a cutting tip should stick in the cutting head, how should it be removed? |
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Definition
| Tap the back of the head with a plastic hammer. |
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Term
| 15. How can cutting torch tip seals be repaired? |
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Definition
| By using a reamer designed for the specific torch tip and head, or new fiber packings are available for tips with packings, or it can be sent out for repair. |
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Term
| 16. Why is the oxygen valve turned on before starting to clean a cutting tip? |
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Definition
| To blow out any dirt loosened during the cleaning. |
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Term
| 17. Why does the preheat flame become slightly oxidizing when the cutting lever is released? |
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Definition
| This occurs because of a rise in line pressure when the high flow of oxygen through the cutting orifice stops. |
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Term
| 18. What causes the tiny ripples in a hand cut? |
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Definition
| The operator's heartbeat. |
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Term
| 19. Why is a slight forward torch angle helpful for cutting? |
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Definition
| The angle helps the flame preheat the metal, keeps some of the reflected flame heat off the tip, aids in blowing dirt and oxides away from the cut, and keeps the tip clean for a longer period of time because the slag is less likely to be blown back onto it. |
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Term
| 20. Why should cans, drums, tanks or other sealed containers be opened with a cutting torch? |
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Definition
| The sparks and oxygen cutting stream may cause even nonflammable residue inside to burn or explode. |
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Term
| 21. Why is the torch tip raised as the cutting lever is depressed when cutting a hole? |
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Definition
| By raising the torch tip away from the metal, the amount of sparks blown into the air is reduced, and the tip is kept cleaner. |
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Term
| 22. Why are the preheat holes not aligned in the kerf when makin a bevel cut? |
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Definition
| The flame would be directed toward the smaller piece and the sharpest edge when cutting a bevel and this would damage the edge. |
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Term
| 25. What is the best way to set the oxygen pressure for cutting? |
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Definition
| Increase the pressure slowly and readjust the flame as you watch the length of the clear cutting stream in the center of the flame. When the cutting stream becomes shortened because of turbulence, reduce the oxygen pressure until the flame lengthens once again. |
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Term
| 26. What metals can be cut with the oxyfuel gas process? |
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Definition
| Any metal that will rapidly oxidize, such as iron, low-carbon steel, magnesium, titanium and zinc. |
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Term
| 27. Why is it important to have extra ventilation and/or a respirator when cutting some used metal? |
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Definition
| They may be oily, dirty, or have been painted and produce very dangerous fumes when they are cut. |
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Term
| 28. What factors regarding a cut can be read from the sides of the kerf after a cut? |
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Definition
| It will show what was correct or incorrect with the preheat flame, cutting speed, and oxygen pressure. |
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Term
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Definition
| It's slag that is attached solidly to the bottom edge of a cut, and it requires a lot of chipping and grinding to be removed, because thate is 30-40% or more unoxidized iron in it. |
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Term
| 30. Why is it important to make good-quality cuts? |
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Definition
| Properly cut metal may be assembled and welded with little or no postcutting cleanup, but poor quality cuts require more time to clean up than is needed to make the required adjustments to make a good weld. |
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Term
| 31. Describe the methods of controlling distortion when making cuts. |
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Definition
| Making two parallel cuts on the smae plate at the same speed and time; or, starting the cut a short distance from the edge of the plate, skipping other short tabs every 2-3 feet, and then cutting the remaining tabs once the part cools. |
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Term
| 32. How does cutting small diameter pipe differ from cutting large diameter pipe? |
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Definition
| Small-diameter pipe can be cut without changing the angle of the torch, but on larger-diameter pipe the torch must be kept at a right angle to the surface of the pipe. |
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