1. Weld and structural areas of concern identified — typically high-stress structural connections and known fatigue-prone details 2. ACFM scan run along the weld through the existing coating 3. Crack indications sized (length and depth estimate) and logged at the point of detection 4. Findings mapped onto the 3D hull model with the supporting scan data

ACFM Weld & Hull Crack Inspection

Alternating Current Field Measurement to detect surface-breaking fatigue cracks through paint on structural hull welds, mapped onto the 3D twin.

Camera, lighting, and manipulator array on an inspection-class ROV

Overview

What This Involves

Alternating Current Field Measurement (ACFM) detects and sizes surface-breaking cracks in steel through the coating, without the surface preparation magnetic particle inspection requires — well suited to in-water structural welds where grinding back to bare metal isn't practical. Every crack indication found is sized and mapped directly onto the vessel's 3D digital twin, alongside the video record of the read.

Method

How It's Done

Weld and structural areas of concern identified — typically high-stress structural connections and known fatigue-prone details

ACFM scan run along the weld through the existing coating

Crack indications sized (length and depth estimate) and logged at the point of detection

Findings mapped onto the 3D hull model with the supporting scan data

Output

Deliverable

A crack-sizing report with every indication mapped onto the 3D model, without stripping the coating.

Fit

Who It's For

Owners and surveyors investigating known fatigue-prone structural details or following up a reported indication.

Frequently Asked

What does ACFM Weld & Hull Crack Inspection involve?

How does it work?

Weld and structural areas of concern identified — typically high-stress structural connections and known fatigue-prone details
ACFM scan run along the weld through the existing coating
Crack indications sized (length and depth estimate) and logged at the point of detection
Findings mapped onto the 3D hull model with the supporting scan data

What's the deliverable?

A crack-sizing report with every indication mapped onto the 3D model, without stripping the coating.

Who is ACFM Weld & Hull Crack Inspection for?

Owners and surveyors investigating known fatigue-prone structural details or following up a reported indication.

Also in Vessel & Maritime Husbandry

Interactive 3D Digital Twin Hull Audits

A complete photogrammetric 3D scan of a hull, rudder, and propeller, delivered as a shareable model a client can rotate, zoom, and measure directly.

UWILD Class Inspections with 3D Mapping

Underwater Inspection in Lieu of Drydocking for DNV, Lloyd's, and ABS class, backed by an interactive 3D model with clickable video callouts for survey sign-off.

In-Water Ultrasonic Thickness (UT) Testing

Steel plate thickness measurement on hulls, sea chests, and ballast tanks, with every sounding georeferenced and pinned to the vessel's 3D digital twin.

Pre-Purchase & Insurance Hull Surveys

Rapid 3D digital baseline mapping for buyers, charter fleets, and insurance adjusters to verify structural condition or document grounding damage.

Propeller & Bow Thruster Disentanglement

Inspecting and clearing fishing line, rope, or netting wrapped around shafts and thrusters using a subsea robotic claw.

Spot Biofouling & Propeller Cleaning

Subsea water jets to clean localized marine growth off propellers or weld lines before NDT testing or high-detail 3D scanning.

Available Near

Kotor Bay, Montenegro

Discuss ACFM Weld & Hull Crack Inspection

← All services