Everything Flashcards
1
Q
How many primary views in orthagraphic projection and what are they?
A
3: top, front and side
2
Q
How many views can be determined with orthographic projections?
A
Six
3
Q
What’s the difference been cast iron and steel?
A
Carbon
4
Q
What two things does grade indicate?
A
Degree of strength and oxidation
5
Q
What pressure is acetylenes critical point?
A
28 psi
6
Q
What kind of threads do oxygen cylinders have?
A
Right hand threads
7
Q
Acetylene is unstable above what pressure?
A
15 psi
8
Q
What kind of threads and fittings does an acetylene cylinder have?
A
Internal left hand threads and notched fittings
9
Q
What part of undercut is measured?
A
Depth not width
10
Q
Over what thickness of material does it need preparation?
A
5/8»
11
Q
What are the two types of pictural drawings and describe them in one word.
A
- Perspective drawings: true photos
- Isometric drawings: distorted photos
12
Q
What does the auxiliary view show?
A
Slanted surface
13
Q
What are the four types of sectional view?
A
- Full section
- Half section
- Broke section
- Revolved section
14
Q
What are baseline dimensions primarily used for?
A
Machinery fabrication
15
Q
What is another name for notational dimensioning?
A
Linear
16
Q
What is a characteristic of notational dimensioning?
A
Often repetitious
17
Q
What are running dimensions primarily used for?
A
Structural fabrication of columns, beams and trusses
18
Q
Name this type of dimension:
All size and location dimensions originate at a single edge and shave a single dimension.
A
Running dimensions
19
Q
What is required when dimensioning curved surfaces?
A
Centerline to properly locate
20
Q
Square groove butt joints are used when: (2 things)
A
Material is 3.2 mm (1/8’’) or less with oxy-acetylene welding
21
Q
What are closed corner joints recommended for?
A
Light gauge sheet metal
22
Q
What type of joints are used to join metals of different thicknesses?
A
Lap joints
23
Q
What is buttering intended for?
A
Buildup to provide a buffer or a transition for another surface weld
24
Q
Hard facing creates a hard or tough surface to control what?
A
Wear
25
Name the weld positions by number:
1: flat position
2. Horizontal
3. Vertical
4. Overhead
5. Pipe - axis of pipe fixed horizontally
6. Pipe - axis of pipe fixed at 45• incline
26
The groove angle for prequalified joints is usually smaller is SAW or SMAW? What are these abbreviations and indicate the heat input.
Smaller for SAW, submerged arc welding, (high heat input) than SMAW, shielded metal arc welding, (low heat input)
27
Name a welding process where the electrode has a coating.
SMAW - shielded metal arc welding
28
A single groove is usually for thinner plates of what size or less?
20 mm or less
29
What type of joints are typically used for thicker material?
J or U-groove
30
What angle is typically used for plate?
30•
31
What angle is typically used for pipe ends?
37.5•
32
What angle is typically used on V-grooves (wider bevel than normal)?
45•
33
What four types of groove welds typically require less filler metal?
1. Single bevel
2. Single J
3. Double bevel
4. Double J-Groove
34
What is the quickest and easiest method of preparing straight edges on a plate up to 20 mm (3/4’’) thick?
Shearing
35
How is an abrasive saw different than a band or disc saw?
It wears metal away like a grinder
36
True or false
Planing has the advantage of flattening warping issues in materials that are in excess of 20 mm (3/4’’)
False
37
Oxy-fuel gas cutting can also be used for gouging steel plates. This method is limited to thickness up to what?
25 mm (1’’)
38
Oxy-fuel gas cutting is a rapid form of what?
Oxidation (rust)
39
What type of metals cannot be cut with the oxy-fuel process and why?
Aluminum, stainless steel, other metals that can’t be oxidized
40
Oxy-fuel gas shape-cutting machines are sometimes called?
Profile machines
41
What does CAC-A and AAC stand for?
Carbon Arc Cutting - Air
Air Arc Cutting
42
This electrode shape is required with semi-automatic and automatic machines to permit continuous cutting.
Jointed
43
This electrode shape can produce both a shallow and a broad groove.
Half round
44
This electrode shape is mainly used to make wide, rectangular and shallow grooves.
Flat
45
This electrode shape is a good general-purpose solution for removing metal and maintaining a consistent tip size.
Round pointed
46
What type of materials can PAC/PAG be used on?
Any conductive materials
47
What type of current is the plasma gas ionized by?
High voltage direct current
48
How much hotter is the plasma jet over the oxy-acetylene?
10x hotter
49
Where does the current travel in the non-transferred arc mode?
From the tungsten electrode to the torch nozzle through arcing, no current going through the workpiece
50
Where does the current travel in the transferred arc mode?
Through the workpiece, which must be grounded
51
What direction do you cut for shapes or holes?
Clockwise for outside cuts, counterclockwise for inside cuts
52
Surface hardening in the HAZ is minimal when using what as the plasma gas?
Oxygen
53
PAC uses what type of electrode?
Hafnium
54
What is laser an acronym for?
Light amplification by stimulated emission of radiation
55
What are the two primary types of lasers?
Solid state and gas
56
What thicknesses can be laser cut?
1/2’’ to 1’’
57
What type of cut does a laser produce?
Cleaner towards the top, rougher towards the bottom
58
Water jet cutting operates on the principle that a high-velocity water jet (_______ m/s) under high pressure (________ psi) can erode many materials.
500-100 m/s
30,000-87,000 psi
59
What is the centreline used to indicate?
The centre of holes and cylinders
60
How much should extension lines be separated by?
1.6 mm (1/16’’)
61
What are phantom lines used to indicate?
Alternate positions of moving parts
62
What are the two different types of leader lines?
1. Arrowhead
2. Black dot
63
What type of dimensions are used for welded fabrication of tanks, hoppers, bases and frames when tolerance is not rigid?
Conventional dimensions
64
The angle or inclination a structural member makes with reference to a horizontal position is called a _______ or a ________.
Slope or bevel
65
The two numbers that show the slop or the bevel are called what?
The rise and the run
66
The thickness of a steel sheet may be specified by either a ___________ or in ___________.
Gauge number or in millimeters
67
When the G.A. Is large, the material is what?
Thinner
68
Plates are commonly designated with what letters followed by thickness x width x length.
PL
69
How are HSS shapes classified?
Actual Outside Dimension x Actual Outside Dimension X Wall Thickness
70
For rectangular HSS, what dimension is always listed first?
The longest side
71
What does a note stating that a bolt is A325-3/4’’ *diameter symbol* 10 UNC indicate?
Bolt is 325 grade, with a 3/4’’ diameter, 10 threads per inch and is a Unified National Coarse thread.
72
There are three classes, what are they and briefly describe:
Class 1: allows for greatest tolerances
Class 2: allows for less tolerances than class 1
Class 3: indicates an extremely close fit with the least tolerance
73
What does UNC and UNF stand for?
United National Course and United National Fine
74
Unless otherwise specified in the specification, the thread is what kind of thread?
Right handed thread
75
What does BC stand for
Bolt Circle or Bolt Centre
76
What did BP stand for?
Base Plate
77
What does ELL stand for?
Elbow
78
What does F & D stand for?
Flanged and Dished
79
What does GR stand for?
Grade
80
What does HSS stand for?
Hollow structural steel
81
What does JE stand for?
Joint efficiency
82
What does NPS stand for?
Nominal Pipe Size
83
A spool is a collection of what?
Pipes, associated components and fittings that form a required assembly or subassembly to be fabricated and shipped
84
What is the takeoff formula?
Takeoff = (centre to centre length) - (total length of fittings) - (total length of gaps)
85
In lap joints, the min overlap of parts shall be what? And not less than what? While the gap between mating surface should not exceed what?
- Min overlap should be 5x the thickness of the thinner part joined
- Not less than 25 mm
- Gap not exceeding 2 mm
86
A disadvantage of a T joint is the flange must be how much bigger than the fillet weld size to permit the weld bead to be deposited?
2x
87
What is the formula for theoretical throat?
TT = leg x 0.707
88
The strength of a fillet weld is governed by what?
The effective throat thickness (shortest distance from the root of weld to its face, less any convexity)
89
What are the two types of fillet welds?
Continuous and intermittent
90
The diameter of the electrode or wire is chosen based on what?
Size of the groove angle (should be as small as possible)
91
Why are unequal double groove preparations made for thicker plates?
To minimize distortion
92
To prevent incomplete fusion due to heat absorption from one plate being bevelled and the other not, what can be done?
Direct the arc against the unbevelled plate
93
Single Bevel, Single J, Double Bevel and Double J Groove Welds all have what in common?
Less filler metal is required
94
What is the main advantage of shearing?
No heat effect in metal (no HAZ)
95
Saws are versatile and effective for what three things?
Cutting, shaping or bevelling
96
Bevelling by grinding is usually limited to a bevel depth of what?
3-5 mm
97
What type of reaction is caused by Oxy-Fuel Cutting (OFC)?
Chemical
98
What colour is the oxygen hose and what colour is the acetylene hose?
Oxygen = green
Acetylene = red
99
For a neutral oxy acetylene flame, what is the ratio that’s needed?
1:1
100
For a carburizing (excessive acetylene) flame, what ratio is needed?
0.9 - 1.0
101
For an oxidizing (excessive oxygen) flame, what ratio is necessary?
1.5-1.0
102
What is the result of distortion during the OFC of light gauge sheet metals?
Considérable buckling and warping
103
When cutting and bevelling quenched and tempered steels or heat treatable low alloy or higher chromium materials, what may need to be removed?
The flame cut affected edge
104
What type of current is used in carbon arc gouging?
Constant current (CC)
105
CC is used in carbon arc gouging provided they have a high open circuit voltage of at least how many volts?
60 volts
106
CAC-A is thought of as a cutting process, but it is frequently used to what?
Remove weld defects when repairing or modifying existing weldments
107
Plasma is an ionized gas that is created how?
Superheating a gas so its molecules are separated into ionized atoms
108
What type of current ionizes the gas in PAC?
DC
109
What are two common faults when using lap joints?
Overlap and convex weld bead profile
110
Intermittent fillet weld are mostly used on lap and T joints and sometimes used on what?
Square butt joints
111
Fillet welds are used to make:
Lap joints, T joints or corner joints
112
What does prequalified joint status allow ?
Allows the regulatory authority to approve the procedure without mechanical testing
113
DCEN, DCEP or AC is used when advantages of the DCEP polarity is needed?
AC
114
DCEN, DCEP or AC is used for welding metals such as aluminum and magnesium?
AC
115
DCEN, DCEP or AC is also known as reverse polarity and seldom used for GTAW?
DCEP
116
DCEN, DCEP or AC is the most common current type and polarity used for GTAW?
DCEN
117
When setting the AC balance to perform catholic cleaning, what must be increased?
Time in the electrode POSITIVE side of the AC sine wave
118
What is the result of using pulsed GTAW?
Decreased heat input resulting in less distortion
119
What feature of pulsed current maintains a constant arc throughout the process?
Background current
120
What is a tungsten alloy electrode with green on it?
Pure tungsten
121
What is a tungsten alloy electrode with yellow on it?
1% thorium oxide
122
What is a tungsten alloy electrode with red on it and what’s the current?
2% thorium oxide
AC & DC
123
What is a tungsten alloy electrode with a brown band on it? What current?
0.25% zirconia oxide
AC
124
What is a tungsten alloy electrode with a black band on it? Current?
1% lanthanum oxide
AC & DC
125
What type of tungsten produces radioactive dust when ground?
Thoriated tungsten
126
What is the result of using excessive current when welding with GTAW?
Electrode erosion, resulting in weld metal contamination
127
What does a blue/purple or blackened end of a tungsten electrode indicate?
Insufficient flow of shielding gas, resulting in oxidation of tungsten
128
When using a balled or rounded end for an alloyed tungsten electrode profile, what is the ideal size of the ball?
Equal to diameter of the electrode
129
Argon-hydrogen mixtures are used with GTAW on which metals?
Stainless steels
130
With GTAW, a longer arc length will concentrate the heat of the arc, resulting in deeper penetration.
True or False
FALSE
131
Where should the filler metal be added when manually welding with GTAW?
At the leading edge of the weld puddle
132
When would pulsed GTAW be beneficial?
When welding thin sheet metal out of position
133
The gas metal arc welding process used what type of gases?
Both inert gases and active gas mixtures
134
GMAW is more forgiving than SMAW and FCAW?
True or false
True
135
E7018 electrodes should only be exposed to the atmosphere for up to how long?
A few hours
136
What is the drawback of MCAW when used in production?
Higher associated costs
137
What is the main advantage of using the GTAW process ?
High productivity welding with no post weld cleaning required
138
What type of cores worse is most suitable for open air field work?
Metal-cored wire
