Exam Cheat Sheet · Quick Reference
Mississippi Welding
Mississippi · PSI Services Contractor
Verified, not estimated. Every figure below is drawn from the official exam structure we maintain — question counts, passing standard and topic weighting. Practice questions are grounded in the source law with statute citations. We omit any figure we can't verify rather than guess at it.
Total questions
60
Passing score
70%
Exam time
120 min
Administered by
PSI Services Contractor
Format
Reference materials allowed
Mississippi State Portion 60 questions
Oxyacetylene Welding and Cutting
11 Q · 18%
Oxyacetylene welding equipment components and assemblyWelding flame types and adjustment (neutral, carburizing, oxidizing)Cylinder safety, handling, and storagePressure regulators, gauges, and hose fittingsTorch startup, shutdown, and leak testing proceduresBackfire and flashback causes and preventionOxyfuel gas cutting process, tips, and working pressuresWelding joint types, positions, and quality inspection
Blueprint and Plan Reading
6 Q · 10%
AWS welding symbols and their components (reference line, arrow, tail, weld symbol)Five basic weld joint types (butt, lap, corner, T-joint, edge)Welding positions and AWS position designations (1G/2G/3G/4G, 1F/2F/3F/4F)Reading groove weld dimensions (root opening, groove angle, depth of bevel, groove weld size)Fillet weld size, leg, and throat dimensionsOrthographic projection and multiview drawing interpretationLine types on mechanical drawings (object, hidden, centerline, dimension, extension, cutting plane, section, leader lines)Title block information and drawing scale
Brazing
5 Q · 8%
Brazing vs. braze welding definitions and principles (capillary action, temperature requirements, AWS definitions)Joint design and clearance for brazing and braze welding (fit-up, joint types, dissimilar metal expansion)Base metal cleaning methods (chemical cleaning, mechanical cleaning, pickling, degreasing)Flux selection, composition, and application methods (AWS classifications, forms, application techniques)Brazing filler metal selection by base metal combination (AWS classifications, solidus/liquidus temperatures, service temperatures)Torch tip selection, flame adjustment, and working pressures for brazing and braze weldingStep-by-step brazing and braze welding procedure (heat application, filler metal addition, joint cleaning)Safety precautions and health hazards (cadmium/beryllium fumes, ventilation, PPE, toxic flux handling)
Pipe Welding
6 Q · 10%
Pipe joint preparation (beveling, root face, root opening dimensions)Welding positions for pipe (1G, 2G, 5G, 6G) and directional techniques (uphill vs. downhill)Root pass welding techniques and keyhole methodIntermediate and cover pass procedures (pass sequence, electrode selection, weave patterns)GTAW root bead welding process and equipmentPipe fit-up, alignment tools, tack welding, and featheringPipe welding defects (causes, prevention, and repair)Welder and procedure qualification standards (ASME, API 1104)
Materials
10 Q · 17%
Ferrous metal classification and carbon content rangesPhysical and mechanical properties of metals (tensile strength, ductility, hardness, toughness, brittleness)Iron-carbon phase diagram and microstructural constituents (ferrite, pearlite, austenite, martensite, cementite)SAE/AISI/ASTM steel numbering systemsStainless steel types and weldability characteristicsNonferrous metals and alloys (aluminum, copper, brass, bronze, titanium) and their welding considerationsHeat treatment processes (annealing, normalizing, quenching and tempering, stress relieving)Metal identification methods (spark test, torch test, fracture test, magnetic test)
SMAW
9 Q · 15%
SMAW equipment components and power source types (AC, DC, inverter, engine-driven)Electrode classification system (AWS numbering, covering types, polarity, position designations)Current and polarity selection (DCEN, DCEP, AC) and effects on penetration and depositionArc striking, arc length control, and travel/work angle techniquesWeld bead types and electrode motion (stringer, weave, whip-and-pause, Z-weave)Weld defects and quality inspection (undercut, porosity, slag inclusion, overlap, incomplete fusion)Multiple-pass pipe welding procedures (root pass, intermediate passes, cover pass)Electrode storage, handling, and reconditioning (low-hydrogen electrode care, drying ovens)
GTAW
9 Q · 15%
Current polarity selection (DCEN, DCEP, AC) and effects on penetration and cleaning actionTungsten electrode types, color codes, and preparation methodsShielding gas selection and flow rate settingsGTAW equipment setup including power source controls, torch assembly, and remote current controlWelding techniques for joint types in all positionsRoot bead welding procedure for pipe using GTAWPulsed arc GTAW and special current features (upslope, downslope)GTAW troubleshooting and weld defect identification
Testing and Inspection
4 Q · 7%
Nondestructive examination (NDE) methods (visual, magnetic particle, liquid penetrant, ultrasonic, radiographic, eddy current)Destructive testing methods (bend, tensile, nick break, peel, impact, hardness, macroetch)Welding procedure specification (WPS) purpose, variables, and categories (qualified, prequalified, standard)Procedure qualification record (PQR) requirements and documentationWelder performance qualification testing (positions, specimens, acceptance criteria)Common pipe welding defects and their causes (porosity, slag inclusions, undercutting, cracking, lack of fusion)Essential versus nonessential welding variables and conditions requiring requalificationWelding codes and standards (AWS, ASME, API) and their jurisdictional scope
Key Distinctions
BrazingvsBraze Welding
Brazing distributes filler metal by capillary action between closely fitted surfaces, while braze welding does NOT rely on capillary action.
Chapter 17 Brazing and Braze Welding, Section 17.1BrazingvsSoldering
Brazing uses filler metal with a liquidus above 840°F (450°C), while soldering is performed below 840°F (450°C).
Chapter 17 Brazing and Braze Welding, Section 17.1Two-Stage Acetylene Regulator (1st stage)vsTwo-Stage Oxygen Regulator (1st stage)
The first stage of a two-stage acetylene regulator reduces pressure to ~50 psig, while a two-stage oxygen regulator first stage reduces to ~200 psig.
Oxyfuel Gas Welding Equipment and Supplies, Section 12.4.3Acetylene Hose Fitting NutvsOxygen Hose Fitting Nut
The acetylene nut has a groove machined around its six sides and uses left-hand threads, while the oxygen nut has flat smooth sides and uses right-hand threads.
Oxyfuel Gas Welding Equipment and Supplies, Section 12.5Neutral Oxyacetylene FlamevsOxidizing Flame
A neutral flame produces a smooth, glossy weld pool at ~5589°F, while an oxidizing flame causes the weld pool to bubble and spark excessively.
Oxyfuel Gas Welding, Section 13.1.3BackfirevsFlashback
A backfire is a momentary flame extinction or pop at the torch tip, while a flashback is a sustained backfire that continues burning back through the torch and into the hoses.
Oxyfuel Gas Welding, Section 13.2.9Fillet Weld Position Designation (F)vsGroove Weld Position Designation (G)
Fillet welds use the 'F' suffix (1F–4F) while groove welds use the 'G' suffix (1G–4G), with numbers 1–4 indicating flat, horizontal, vertical, and overhead positions respectively.
Chapter 3, Section 3.4Arrow-Side Weld Symbol PlacementvsOther-Side Weld Symbol Placement
Arrow-side weld information is always placed below the reference line, while other-side weld information is always placed above the reference line.
Chapter 3, Section 3.5.3Austenitic Stainless SteelvsFerritic/Martensitic Stainless Steel
Austenitic stainless steel is non-magnetic and will not attract a magnet, while ferritic and martensitic stainless steels are magnetic.
Modern Welding, Chapter 28Spheroidizing Heat TreatmentvsAnnealing/Normalizing Heat Treatment
Spheroidizing heats steel to just below the A₁ lower critical temperature to improve ductility, while annealing and normalizing heat above the A₃ critical temperature.
Modern Welding, Chapter 29, Section 29.4.5 (Spheroidizing)AC GTAW Aluminum Weld Pool WidthvsCarbon Steel Stringer Bead Width
AC GTAW on aluminum produces a weld pool ~3 to 4 times the electrode diameter, while carbon steel stringer beads are typically only 1½ to 2 times the electrode diameter.
Modern Welding, Chapter 10, Section 10.12.2Root Pass RestartvsIntermediate Pass Restart
For a root pass restart, the arc is struck 3/8" back on the existing bead, while for an intermediate pass restart, the arc is struck 3/8" in front of the weld crater.
Modern Welding, Page 23-27Key Terms
Maximum Safe Working Pressure – Acetylene Oxyfuel Gas Welding Equipment and Supplies, Section 12.3.1 and 12.3.3
Per Oxyfuel Gas Welding Equipment and Supplies Section 12.3.1/12.3.3, acetylene must never be used above 15 psig (103 kPa) because it becomes unstable and hazardous at higher pressures.
Flashback Arrestor Replacement Temperature Oxyfuel Gas Welding Equipment and Supplies, Section 12.6
Per Oxyfuel Gas Welding Equipment and Supplies Section 12.6, a flashback arrestor cannot be reused after reaching 220°F (104°C) because its heat-sensitive check valve has been triggered.
Regulator Gauge Maximum Working Pressure Oxyfuel Gas Welding, Section 13.8.5
Per Oxyfuel Gas Welding Section 13.8.5, the working pressure used on a regulator gauge must never exceed two-thirds of the gauge's maximum calibration value.
Cracking the Valve Oxyfuel Gas Welding, Section 13.2.1
Per Oxyfuel Gas Welding Section 13.2.1, cracking the valve means quickly opening and closing the cylinder valve slightly to blow out dirt and particles from the outlet before attaching a regulator.
Keyhole Technique Oxyfuel Gas Welding, Section 13.4.1
Per Oxyfuel Gas Welding Section 13.4.1, the keyhole technique involves waiting until a keyhole shape forms at the leading edge of the weld pool before adding filler metal, ensuring 100% penetration on butt joints.
Torch Travel Angle (Oxyacetylene) Oxyfuel Gas Welding, Section 13.3.1
Per Oxyfuel Gas Welding Section 13.3.1, the proper travel angle between the torch axis and a line perpendicular to the weld axis when creating a continuous weld pool is 35°–45°.
Acetylene Cylinder Filler Porosity Oxyfuel Gas Welding Equipment and Supplies, Section 12.3.1
Per Oxyfuel Gas Welding Equipment and Supplies Section 12.3.1, federal safety regulations require the inert porous filler material inside an acetylene cylinder to cure to a porosity of 85% to safely absorb acetylene dissolved in acetone.
Cadmium Oxide Fume Exposure Limit Chapter 17 Brazing and Braze Welding, Section 17.10
Per Chapter 17 Brazing and Braze Welding Section 17.10, the maximum permissible exposure limit for cadmium oxide fumes is 0.1 milligrams per cubic meter of air during a daily eight-hour work period.
Overlap (Weld Defect) Modern Welding, Chapter 6, Page 143
Per Modern Welding Chapter 6, overlap is unfused metal lying on the base metal surface at the weld toe, caused by insufficient heat input from a too-short arc length.
Fillet Weld Leg Chapter 3, Section 3.1 (Fillet Weld discussion near Figure 3-8)
Per Chapter 3 Section 3.1, the leg of a fillet weld is the shortest distance from the toe to the surface of the other piece of base metal.
Brazing vs. Soldering Temperature Threshold Chapter 17 Brazing and Braze Welding, Section 17.1
Per Chapter 17 Section 17.1, the AWS defines brazing as using filler metal with a liquidus above 840°F (450°C), which is the dividing line separating it from soldering.
Copper-Phosphorus (BCuP) Filler Metal Restriction Chapter 17 Brazing and Braze Welding, Section 17.5
Per Chapter 17 Section 17.5, BCuP filler metals must NOT be used on ferrous alloys, nickel-based alloys, or copper-nickel alloys containing more than 10% nickel.
Dip Brazing Flux Restriction Chapter 17 Brazing and Braze Welding, Section 17.4
Per Chapter 17 Section 17.4, fluxes containing water must never be used in dip brazing because the water converts to steam and causes the liquid metal to erupt from the dip bath.
Silver Filler Flux Clear-Liquid Indicator Chapter 17 Brazing and Braze Welding, Section 17.7.2
Per Chapter 17 Section 17.7.2, when brazing with silver-based filler metals the flux turning clear and liquid at ~1100°F (600°C) signals the metal is just below brazing temperature and filler metal addition should begin.
Cobalt-Based Filler Metal Service Temperature Chapter 17 Brazing and Braze Welding, Section 17.5
Per Chapter 17 Section 17.5, cobalt-based filler metals have the highest upper service temperature of any brazing filler metal at 1900°F (1040°C).