BOILERMAKER TEST 2
Final Examination Questions & Answers with Verified Solutions
2026/2027
1. What primary layout method is used to develop a flat pattern template for a truncated
cone layout on heavy steel plate?
A. Parallel line development
B. Radial line development
C. Triangulation method
D. Direct projection method
Rationale: Radial line development uses converging lines extending from a central apex point, making it
the proper technique for conical transitions and truncated cones.
2. When calculating the flat plate blank size for rolling a cylindrical shell, how is the mean
circumference determined?
A. Outside Diameter multiplied by Pi
B. Inside Diameter multiplied by Pi
C. (Inside Diameter + Material Thickness) multiplied by Pi
D. (Outside Diameter + Material Thickness) divided by Pi
Rationale: Plate stretches on the outside and compresses on the inside during rolling. The neutral axis
lies at the midpoint, so Mean Diameter = ID + Thickness (or OD - Thickness).
3. Which non-destructive testing (NDT) method is best suited for detecting subsurface
volumetric flaws in heavy boiler drum circumferential welds?
A. Liquid penetrant testing
B. Magnetic particle testing
C. Radiographic testing
D. Visual inspection
Rationale: Radiography (X-ray/Gamma ray) penetrates the full wall thickness to reveal internal volumetric
defects like porosity, slag inclusions, and internal lack of penetration.
, 4. What is the primary cause of tube-end cracking during cold roll expansion of boiler
tubes into a tube sheet?
A. Excessive wall reduction beyond recommended percentage limits (over-rolling)
B. Insufficient lubricant on the expander mandrel
C. Low air motor operating pressure
D. Rolling at ambient room temperature
Rationale: Over-rolling thins the tube wall excessively, work-hardening the steel beyond its ultimate
tensile strength limit and causing longitudinal stress cracks.
5. What tool is used to align matching bolt holes when fitting up heavy structural steel
boiler casing panels?
A. Cold chisel
B. Tapered sleever bar or drift pin
C. Center punch
D. Brass alignment drift
Rationale: Tapered drift pins or sleever bars are driven into misaligned holes to leverage heavy steel
plates into exact alignment for bolting or tacking.
6. In boiler rigging, what factor determines the Safe Working Load (SWL) of a wire rope
sling when choking a load?
A. Choking increases the sling capacity by 20%
B. Choking reduces the rated sling capacity by approximately 25% due to the sharp
bend angle
C. Choking maintains 100% of the basket hitch capacity
D. Sling angle does not affect choked hitches
Rationale: A choke hitch bends the wire rope sharply around the fitting, introducing localized bending
stress that reduces the rated capacity to 75% or 80%.
7. What heat treatment process is performed on heavy welded pressure vessels to relieve
residual stress induced by welding?
A. Full annealing
B. Water quenching
C. Post-Weld Heat Treatment (PWHT) / Stress Relieving
Final Examination Questions & Answers with Verified Solutions
2026/2027
1. What primary layout method is used to develop a flat pattern template for a truncated
cone layout on heavy steel plate?
A. Parallel line development
B. Radial line development
C. Triangulation method
D. Direct projection method
Rationale: Radial line development uses converging lines extending from a central apex point, making it
the proper technique for conical transitions and truncated cones.
2. When calculating the flat plate blank size for rolling a cylindrical shell, how is the mean
circumference determined?
A. Outside Diameter multiplied by Pi
B. Inside Diameter multiplied by Pi
C. (Inside Diameter + Material Thickness) multiplied by Pi
D. (Outside Diameter + Material Thickness) divided by Pi
Rationale: Plate stretches on the outside and compresses on the inside during rolling. The neutral axis
lies at the midpoint, so Mean Diameter = ID + Thickness (or OD - Thickness).
3. Which non-destructive testing (NDT) method is best suited for detecting subsurface
volumetric flaws in heavy boiler drum circumferential welds?
A. Liquid penetrant testing
B. Magnetic particle testing
C. Radiographic testing
D. Visual inspection
Rationale: Radiography (X-ray/Gamma ray) penetrates the full wall thickness to reveal internal volumetric
defects like porosity, slag inclusions, and internal lack of penetration.
, 4. What is the primary cause of tube-end cracking during cold roll expansion of boiler
tubes into a tube sheet?
A. Excessive wall reduction beyond recommended percentage limits (over-rolling)
B. Insufficient lubricant on the expander mandrel
C. Low air motor operating pressure
D. Rolling at ambient room temperature
Rationale: Over-rolling thins the tube wall excessively, work-hardening the steel beyond its ultimate
tensile strength limit and causing longitudinal stress cracks.
5. What tool is used to align matching bolt holes when fitting up heavy structural steel
boiler casing panels?
A. Cold chisel
B. Tapered sleever bar or drift pin
C. Center punch
D. Brass alignment drift
Rationale: Tapered drift pins or sleever bars are driven into misaligned holes to leverage heavy steel
plates into exact alignment for bolting or tacking.
6. In boiler rigging, what factor determines the Safe Working Load (SWL) of a wire rope
sling when choking a load?
A. Choking increases the sling capacity by 20%
B. Choking reduces the rated sling capacity by approximately 25% due to the sharp
bend angle
C. Choking maintains 100% of the basket hitch capacity
D. Sling angle does not affect choked hitches
Rationale: A choke hitch bends the wire rope sharply around the fitting, introducing localized bending
stress that reduces the rated capacity to 75% or 80%.
7. What heat treatment process is performed on heavy welded pressure vessels to relieve
residual stress induced by welding?
A. Full annealing
B. Water quenching
C. Post-Weld Heat Treatment (PWHT) / Stress Relieving
