Pressure Vessel Design Quiz

Which type of vessel shape is most efficient for high-pressure applications?

• Cylindrical

• Rectangular

• Spherical

• Conical

Answer explanation

In pressure vessel design, which orientation is typically used to promote phase separation?

• Vertical

• Horizontal

• Inclined

• Inverted

Which vessel orientation typically requires less plot space?

• Horizontal

• Diagonal

• Vertical

• Inclined

What factor limits the height of most cylindrical vessels?

• Cost of materials

• Availability of cranes

• Pressure limit

• Wall thickness requirements

Answer explanation

•Most pressure vessels are at least 2:1 cylinders: 3:1 or 4:1 are most common:

•Distillation columns are obviously an exception: diameter is set by flooding correlations and height by number of trays

•Diameter gets very expensive if > 13.5 ft (4.11m). Why?

Height (length) gets very expensive if > 180 ft (54.86m). Why - limited number of cranes to lift the vessel and transport it to site, leading to expensive on-site fabrication

Which of the following vessels is most common for chemical reactors and storage tanks?

• Spherical

• Rectangular

• Cylindrical

• Cone-bottom

Which vessel support type is generally used for tall, vertical columns?

• Saddle support

• Skirt support

• Brackets

• Legs

Answer explanation

What is the primary inspection focus of a weld line on a vessel?

• Material properties

• Structural integrity

• Corrosion resistance

• Temperature tolerance

The maximum design temperature margin is typically set at:

• 25°F

• 40°F

• 50°F

• 100°F

Answer explanation

•Maximum:

•Highest mean metal temperature expected in operation, including transient conditions, plus a margin

•Margin is typically plus 50°F

•Minimum

•Lowest mean metal temperature expected in operation, including transient conditions, upsets, auto-refrigeration, climatic conditions, anything else that could cause cooling, minus a margin

•Margin is typically -25°F

•MDMT: minimum design metal temperature is important as metals can become brittle at low temperatures

•Designer should allow for possible failure of upstream equipment (e.g., loss of coolant on upstream cooler)

Corrosion allowance typically ranges from:

• 1-2 mm

• 1.5 to 5 mm

• 6-10 mm

• 10-15 mm

Which part of a pressure vessel often requires additional reinforcement?

• Saddle supports

• Shell

• Nozzles

• Head

Answer explanation