120101i Flashcards
Describe the oxy fuel cutting process
Oxy cutting is a controlled process of rapid oxidation in which steel is heated to its kindling temperature and a high-pressure jet of pure oxygen is directed to the heated area metal exposed to the oxygen oxidizes and is blown away by the oxygen jet stream
What two Ferris base metals cannot be cut satisfactorily with an oxy fuel cutting torch
Cast irons and stainless steals
When a piece of metal is cut, it creates a cut gap called the
A) groove
B) bead
C) kerf
D) crater
C) kerf
On a combination cutting torch, the oxygen valve on the torch handle must be
A) close tightly
B) partially open
C) fully open
D) used to adjust to a neutral flame
C) fully open
The rivet cutting tip is designed to
A) make suitable holes for riveted construction
B) facilitate right angle square hole cutting
C) facilitate cutting in confined spaces
D) cut off rivet and bolt heads without disturbing the parent metal
D) cut off rivet and bolt heads without disturbing the parent metal
Which cutting tip has preheat orifices in a smaller pitch circle around the cutting orifice
A) standard cutting tip
B) high speed cutting tip
C) gouging tip
D) rivet cutting tip
B) high speed cutting tip
The larger the orifices on a cutting tip:
A) less gas you burn
B) greater the heat loss
C) faster you cut
D) thicker the plate that you can cut
D) thicker the plate that you can cut
Which metals can you cut easily using the oxy fuel cutting process?
A) cast irons
B) mild steels
C) stainless steel
D) nickel alloys
B) mild steels
Which oxy fuel torch design has the mixer chamber inside one of the tubes leading to the torch head
A) tip mixing
B) high-speed
C) pre-mixing
D) oxygen lance
C) pre-mixing
Explain why you cannot cut non-Ferris metals using an oxy fuel torch
Unlike steel non-Ferris metals will not oxidize or burn progressively
List three methods used for starting a cut on round stock
- Use a chisel to make the surface.
- Drill into the surface.
- Apply a bead of arc weld
List three types of control systems use for mechanized oxyfuel cutting
- Machine tracer guided.
- Magnetic tracer guided.
- Electronic tracer guided.
Templates for magnetic tracers are made of
Steel
Photo electric cells and computer controls are used with ______ tracer guided cutting machines
A) manual
B) machine
C) magnetic
D) electronic
D) electronic
When preheating for flame cutting the metal should be heated until it reaches its
A) liquid state
B) bright yellow colour
C) kindling point
D) transition temperature
C) kindling point
When the cut is rough and the slag accumulates on the bottom edge, the likely cause is
A) using propane fuel gas
B) using oxygen that is only 99.5% pure
C) using a dirty tip
D) using a cutting attachment type torch
C) using a dirty tip
When piercing holes in a plate you should
A) press, the cutting lever sharply to start the cut
B) allow the preheat cones to touch the material surface
C) raise the oxygen pressure by 25%
D) raise the tip when the cutting lever is depressed
D) raise the tip when the cutting lever is depressed
What is likely to happen if the cutting travel speed is too fast
A) productivity increases in your employer is very impressed
B) slag bubbles to the surface and the cutting action eventually stops
C) the tip overheats and begins to backfire
D) clean slag free cut is produced
B) slag bubbles to the surface and the cutting action eventually stops
What is likely the problem if the curve edges are melting back together behind the cut
A) the tip is too large for the material thickness
B) impurities are in the fuel gas
C) the steel has too high carbon content
D) you are running low on fuel gas
A) the tip is too large for the material thickness
If a shop were to switch from acetylene to propane gas for cutting, it would be necessary to
A) purchase all new torches
B) install special fuel, gas regulators
C) check with the manufacturer to determine if the equipment is compatible
D) change to larger size hoses
C) check with the manufacturer to determine if the equipment is compatible
You can determine a good quality cut by
A) inspecting the kerf lines
B) asking the foreman
C) the amount of welding experience the operator has
D) the amount of oxygen and acetylene consumed
A) inspecting the kerf lines
Kerf drag lines on a properly performed shape cut should be
A) irregular in profile
B) curved to match the shape
C) perpendicular to the plate surface
D) horizontally inclined
C) perpendicular to the plate surface
If you noticed the preheat flames changing from neutral to carbonizing during the cutting process, the most most likely caused would be that the
A) oxygen cylinder is nearly empty
B) acetylene consumption is too high
C) acetylene cylinder is nearly empty
D) tip is dirty and requires cleaning
A) oxygen cylinder is nearly empty
What tools can you use to lay out a structural shape?
A) contour marker
B) hammer and centre punch
C) square and level
D) combination square
E) all of the above
E) all of the above