The shipbuilding and marine sector
encompasses new vessel construction, in-service vessel maintenance, offshore
supply vessel and FPSO inspection, and port and terminal infrastructure
assessment. Ships and offshore vessels are complex welded structures operating
in one of the most corrosive environments on earth — salt water, cyclic
loading, and the constant mechanical stress of wave action create a demanding
degradation environment for hull structures, pressure equipment, and machinery
systems.
Inspection in shipbuilding and
marine is governed by classification society requirements — DNV, Lloyd's
Register, Bureau Veritas, ABS, and others — whose survey programmes define the
inspection scope, the frequency, and the acceptance criteria for vessels under
their class. New construction inspection must demonstrate conformance to the
applicable classification rules at each hold point. In-service survey must
demonstrate continued structural integrity, watertight integrity, and machinery
condition within the class renewal cycle.
A vessel whose structural or
machinery condition is not adequately understood represents a safety risk to
crew, cargo, and the marine environment — as well as a commercial and
regulatory risk to the shipowner. Classification survey is the minimum regulatory
requirement. Structural integrity management beyond the class minimum —
particularly for aging vessels, vessels operating in harsh environments, and
offshore assets with complex loading histories — demands a more active
inspection approach.
Ship hull plates, frames,
longitudinals, and welded connections are subject to corrosion from seawater
and cargo, fatigue cracking from cyclic wave loading, and structural damage
from grounding, collision, and cargo handling. Hull inspection requires systematic
thickness survey, close-visual inspection of weld connections, and PAUT for
fatigue crack detection at high-stress structural details.
Ballast tanks, void spaces, and
other confined internal spaces in ships and offshore vessels are among the most
difficult inspection environments — restricted access, poor lighting, uneven
surfaces, and atmospheric risk create both technical and safety challenges.
Internal drone inspection and robotic NDT crawlers significantly reduce the
personnel exposure and time cost of systematic internal tank inspection.
Marine diesel engines, shaft
seals, propeller hubs, and auxiliary machinery are subject to wear, fatigue
cracking, and corrosion-related degradation. Access for inspection is
constrained by machinery arrangement, and many critical components require NDT by
methods appropriate for the material and defect type — MT and PT for surface
cracks in ferrous and non-ferrous components, UT for shaft and component
volumetric assessment.
Ship hull anti-corrosion and
anti-fouling coating systems require periodic inspection to assess condition,
adhesion loss, and cathodic protection effectiveness. Thermal imaging from
drone platforms identifies coating breakdown and moisture ingress patterns
across large hull areas without requiring scaffolding or diver support.
Systematic UT thickness survey of
hull plating, frames, and structural members — supplemented by magnetic crawler
robotic NDT for access-restricted internal surfaces and external hull areas.
Thickness data referenced to classification society diminution allowances for
structural acceptance disposition.
New construction weld inspection
for classification society hold points — PAUT and TOFD for structural and
pressure welds, digital radiography (DR/CR) for weld quality records.
In-service inspection for fatigue cracks at structural connections using PAUT
and ACFM through coating.
Collision-tolerant internal drone
inspection of ballast tanks, cargo tanks, and confined internal spaces —
providing detailed visual condition assessment without personnel entry,
reducing both confined space risk and inspection time.
ACFM for surface crack detection
and sizing at structural connections, weld toes, and high-stress details
through paint and coating — eliminating the preparation and reinstatement cost
of MPI inspection in marine environments where coating integrity is critical.
UAV external survey of vessel
superstructure, funnel, masts, and upper deck structures — providing
close-visual assessment of coating condition, structural deformation, and
mechanical damage from controlled standoff distance without staging or rope
access.