SPED P&ID Reading & Isometric Drawing Interpretation

Question 1

On a piping isometric drawing, the three principal axes are drawn at what angles?

Accepted Answer

One vertical axis and two axes at 30° from horizontal

Answer

Isometric projection uses a vertical axis plus two horizontal-plane axes drawn 30° above the horizontal. The three axes are 120° apart, so east-west and north-south runs both appear at 30°.

Question 2

Which of the following is NOT normally shown on a P&ID?

Accepted Answer

Exact physical routing dimensions and elevations

Answer

A P&ID is a schematic that shows process connectivity, instrumentation and control logic. It is not drawn to scale and does not give physical routing dimensions. Those come from plans, sections and isometrics.

Question 3

In ISA-5.1 symbology, an instrument bubble with a single solid horizontal line through its center indicates the instrument is:

Accepted Answer

Mounted in the primary location (e.g., central control room), normally accessible to the operator

Answer

In ISA-5.1, a plain circle means field mounted. A solid line through the middle means primary location (usually the main control room panel or console) and normally accessible to the operator. A dashed line means a location behind the panel or otherwise not normally accessible.

Question 4

The ISA instrument tag 'FIC' identifies a:

Accepted Answer

Flow Indicating Controller

Answer

The first letter is the measured variable (F = flow). The following letters are functions (I = indicate, C = control), so FIC is a flow indicating controller.

Question 5

A typical piping line number on a P&ID or isometric usually includes which set of information?

Accepted Answer

Nominal size, service/fluid code, sequence number, and pipe class/spec

Answer

Line designations commonly combine nominal pipe size, a fluid/service code, a unique sequence number, and the piping material class. Many also add an insulation or tracing code. Weld and test records are kept separately.

(SPED) Society of Piping Engineers and Designers Certification Practice Test

(SPED) Society of Piping Engineers and Designers Certification Practice Test

SPED P&ID Reading & Isometric Drawing Interpretation