SAMS Hull and Machinery Surveyors 4

Question 1

A surveyor discovers that a vessel's sea cock is a gate valve rather than a ball valve on a below-waterline through-hull. What is the correct disposition?

Accepted Answer

Flag as a deficiency; gate valves are not acceptable sea cocks

Answer

ABYC and SAMS standards require sea cocks to be quarter-turn ball valves or equivalent; gate valves are not acceptable because they cannot be closed quickly in an emergency and are prone to seizure.

Question 2

When inspecting a twin-screw vessel, the surveyor notes that the starboard propeller rotates clockwise when viewed from aft. What should the port propeller rotation be for optimal maneuverability?

Accepted Answer

Counter-clockwise (opposite rotation, outward-turning pair)

Answer

Standard twin-screw practice is outward-turning propellers: starboard turns clockwise (right-hand) and port turns counter-clockwise (left-hand) when viewed from astern, improving low-speed maneuverability.

Question 3

During ultrasonic thickness testing of a steel hull, a surveyor obtains readings 20% below the original design scantlings. According to SAMS practice, how should this be reported?

Accepted Answer

As a significant deficiency requiring immediate structural evaluation

Answer

A 20% reduction in plating thickness represents significant structural wastage that requires evaluation by a naval architect or structural engineer before the vessel can be considered seaworthy.

Question 4

Which document provides the primary regulatory framework for commercial vessel structural standards in the United States?

Accepted Answer

Classification society rules (ABS, DNV)

Answer

For commercial vessels, classification society rules (such as ABS or DNV) provide detailed structural scantling requirements that are referenced or adopted within US Coast Guard regulations.

Question 5

A surveyor finds a crack in a GRP hull running parallel to and adjacent to a longitudinal stringer. What does this pattern most likely indicate?

Accepted Answer

Stress concentration from the stringer hard-point

Answer

Cracks parallel to stringers typically result from the hard-point stress concentration where the stringer terminates or changes section, causing the adjacent laminate to flex and fracture.

(SAMS) Society of Accredited Marine Surveyors Certified Practice Test

(SAMS) Society of Accredited Marine Surveyors Certified Practice Test

SAMS Hull and Machinery Surveyors 4