SPED Piping Design Principles & Standards 2 — Questions and Answers
Question 1: Which ASME code governs the design of process piping in industrial facilities?
- ASME B31.1
- ASME B31.3 (Correct answer)
- ASME B31.4
- ASME B31.8
Correct answer: ASME B31.3
ASME B31.3 is the Process Piping code that governs chemical, petroleum, and other process plant piping systems.
Question 2: What is the purpose of a spectacle blind (figure-8 blind) in piping systems?
- To reduce pipe vibration
- To allow full flow or complete isolation by rotating the blind (Correct answer)
- To measure flow rate through the line
- To absorb thermal expansion
Correct answer: To allow full flow or complete isolation by rotating the blind
A spectacle blind provides a visual indication of line status and allows operators to switch between full flow and complete isolation by rotating the figure-8 plate.
Question 3: In piping isometrics, what does the abbreviation 'BOP' stand for?
- Bottom of Pipe (Correct answer)
- Basis of Process
- Bottom of Platform
- Back of Pipe
Correct answer: Bottom of Pipe
BOP stands for Bottom of Pipe and is used as a reference elevation datum for pipe routing and support design.
Question 4: What is the minimum clearance typically required between insulated pipe surfaces and structural steel per standard practice?
- 1 inch
- 2 inches
- 3 inches (Correct answer)
- 4 inches
Correct answer: 3 inches
Standard practice requires a minimum 3-inch clearance between insulated pipe surfaces and structural members to allow for insulation installation and maintenance.
Question 5: Which type of valve is best suited for throttling service in process piping?
- Gate valve
- Globe valve (Correct answer)
- Ball valve
- Butterfly valve
Correct answer: Globe valve
Globe valves are specifically designed for throttling service because their disc and seat configuration allows precise flow regulation.
Question 6: What does the pipe schedule number indicate?
- The pipe's outer diameter in inches
- The wall thickness relative to pipe size (Correct answer)
- The maximum operating temperature
- The pipe material grade
Correct answer: The wall thickness relative to pipe size
The schedule number is a dimensionless number that, combined with nominal pipe size, determines the wall thickness of the pipe.
Question 7: What is the primary function of an expansion loop in a piping system?
- To increase flow velocity
- To filter particulates from the process fluid
- To accommodate thermal growth without overstressing pipe or equipment (Correct answer)
- To reduce pressure drop across long runs
Correct answer: To accommodate thermal growth without overstressing pipe or equipment
Expansion loops absorb the thermal expansion of pipe runs by flexing, preventing excessive stresses on pipe, fittings, and connected equipment nozzles.
