UTM Ultrasonic Thickness Measurement Project
Independent ultrasonic thickness measurement project involving a 57,850 DWT bulk carrier built in 2018 during technical attendance at Subic Bay, the Philippines.
Project Overview
PAMS Pacific Admiralty Maritime Services carried out an independent ultrasonic thickness measurement project involving a 57,850 DWT bulk carrier built in 2018 at Subic Bay, the Philippines.
The assignment focused on obtaining objective ultrasonic thickness measurement data from the agreed vessel structural areas and organizing the information for technical assessment and reporting.
The project demonstrates the practical application of ultrasonic thickness measurement within an independent marine technical consultancy assignment, where measurement data, structural condition and applicable technical requirements are considered together.
Project Profile
| Project Type | Ultrasonic Thickness Measurement Project |
| Vessel Type | Bulk Carrier |
| Deadweight | 57,850 DWT |
| Year Built | 2018 |
| Project Location | Subic Bay, the Philippines |
| Technical Service | Ultrasonic Thickness Measurement |
| Technical Discipline | Marine Technical Consultancy and Vessel Condition Assessment |
| Inspection Approach | Independent ultrasonic measurement, structural observation and technical documentation |
Project Objective
The primary objective of the project was to obtain reliable ultrasonic thickness measurement information from the agreed structural areas of the bulk carrier.
Thickness measurements provide objective technical data that can assist in evaluating the condition of steel structures and identifying areas where further technical assessment, maintenance consideration or repair planning may be required.
The assignment was approached as an independent technical inspection, with emphasis on accurate measurement recording, traceability of measurement locations and clear technical reporting.
Technical Scope
The project scope covered ultrasonic thickness measurement and associated technical inspection activities within the agreed vessel areas.
Vessel Structural Assessment
Review of accessible structural areas identified within the agreed inspection and measurement scope.
Ultrasonic Thickness Measurement
Ultrasonic thickness readings were obtained at designated measurement locations using suitable measurement equipment.
Measurement Location Control
Measurement results were associated with the applicable structural locations to maintain traceability of the recorded information.
Structural Condition Observation
Accessible visual observations and surface conditions were considered together with the measurement activity where applicable.
Technical Data Review
Available vessel information and relevant technical documentation were considered as part of the overall technical assessment.
Technical Reporting
Measurement information and relevant observations were organized into a structured technical record for the intended project purpose.
UTM Measurement Approach
Ultrasonic thickness measurement is a non-destructive technique used to determine the remaining thickness of suitable metallic structures without destructive removal of the inspected material.
Within a bulk carrier inspection, UTM data can provide quantitative information concerning structural thickness and can support the wider technical assessment of corrosion, wastage and structural condition.
Inspection Planning
The agreed measurement scope and vessel structural locations are reviewed before the measurement activity. Accessibility, safe access and practical inspection conditions are considered.
Surface & Access Assessment
Surface condition, coatings, corrosion, scale and accessibility are considered because these factors can influence measurement execution and coverage.
Thickness Readings
Ultrasonic readings are obtained at the designated measurement points and recorded against the relevant structural locations.
Results Documentation
Measurement information is organized into a structured record that can be reviewed together with vessel structural information and applicable technical requirements.
Structural Measurement Areas
Depending on the agreed inspection scope, ultrasonic thickness measurement on a bulk carrier can cover selected hull, deck, cargo hold and internal structural areas. Actual measurement locations are determined by the project scope, accessibility, vessel condition and applicable requirements.
Hull & Shell Structures
- Shell plating
- Side shell structures
- Bottom structural areas
- Accessible hull structural members
Cargo Hold Structures
- Cargo hold plating
- Bulkhead structures
- Frames and stiffeners
- Other accessible structural components
Deck Structures
- Accessible deck plating
- Deck structural members
- Selected areas exposed to corrosion
- Locations requiring thickness verification
Internal Structures
- Accessible internal plating
- Floors and girders
- Stiffeners and structural members
- Other areas included in the agreed scope
Technical Inspection Methodology
PAMS applies a structured technical methodology to ultrasonic thickness measurement projects. The objective is to maintain traceability between the inspection scope, physical measurements, structural locations, technical observations and final reporting.
Scope Review
Review of vessel information, project requirements, requested measurement scope and available technical documentation.
Access & Preparation
Identification of accessible measurement areas and consideration of surface condition, structural configuration and practical inspection conditions.
UTM Readings
Ultrasonic thickness measurements are obtained at the designated structural locations and recorded for subsequent technical assessment.
Results & Assessment
Measurement information and relevant observations are organized into a structured technical report supporting the intended project purpose.
MSC.553(108) & Stricter Oversight of Thickness Measurement Firms
This project is also relevant to the evolving regulatory environment governing firms engaged in thickness measurement of ship hull structures. IMO Resolution MSC.553(108) introduced amendments to the 2011 ESP Code concerning the procedures for approval and certification of firms engaged in thickness measurement of hull structures.
The amendments entered into force on 1 January 2026 and place greater emphasis on verification of the firm's organization, management and technical capability. Following satisfactory document review, the Administration audits the firm to ascertain that it is duly organized and managed in accordance with the submitted documentation and capable of conducting thickness measurement of hull structures.
Organization & Management
Project Approach: The assignment is performed within a defined technical scope, with responsibilities and inspection activities organized to maintain consistency and traceability.
Technical Capability
Project Approach: The measurement process is structured around suitable ultrasonic measurement techniques and the technical requirements applicable to the assignment.
Measurement Procedures
Project Approach: Measurement locations, readings and relevant inspection observations are documented in a controlled technical record.
Personnel Competence
Project Approach: Technical inspection activities require competent personnel capable of carrying out the agreed measurement and assessment tasks.
Equipment & Calibration
Project Approach: Measurement equipment suitability and applicable calibration or verification requirements are considered as part of reliable thickness measurement practice.
Records & Reporting
Project Approach: Measurement results and technical information are organized into a traceable record suitable for subsequent technical review.
From Measurement to Controlled Technical Evidence
The significance of MSC.553(108) is that thickness measurement firms are subject to a more structured verification process. The focus is therefore not simply whether a thickness value has been obtained, but whether the firm has the organization, management and capability necessary to conduct thickness measurement of hull structures in accordance with the applicable requirements.
In practical project terms, this reinforces the importance of controlled measurement procedures, appropriate equipment, competent personnel, accurate location identification, reliable records and clear technical reporting.
PAMS incorporates these principles into its independent technical approach by treating ultrasonic thickness measurement as a structured technical inspection rather than as a collection of isolated numerical readings.
Technical Assessment of Measurement Results
Ultrasonic thickness measurements are assessed within the wider structural and technical context of the vessel. Individual measurements should not be considered in isolation from the structural location, original construction data, previous measurement records, corrosion condition and applicable technical criteria.
Remaining Thickness
Assessment: Recorded ultrasonic measurements provide objective information concerning the remaining thickness of the examined structural locations.
Corrosion & Wastage
Assessment: Measurement data can assist in identifying areas where corrosion or wastage may require additional technical review.
Historical Comparison
Assessment: Where previous measurement records are available, comparison may assist in evaluating changes in structural thickness over time.
Structural Context
Assessment: Measurement values are considered in relation to the structural member, vessel location and applicable technical requirements.
Technical Documentation & Reporting
Accurate measurement information must remain traceable from the physical inspection through to the final technical record. The reporting process therefore considers both numerical measurement data and the relevant technical context.
Measurement Records
- Measurement location identification
- Recorded ultrasonic thickness values
- Relevant structural reference information
- Applicable inspection observations
Technical Review
- Review of available vessel information
- Consideration of structural condition
- Comparison with historical information where available
- Identification of areas requiring further review
Project Outcome
The project produced an independent technical record of ultrasonic thickness measurement information obtained from the agreed structural areas of the 57,850 DWT bulk carrier at Subic Bay.
Technical Value of the Project
- Objective ultrasonic thickness measurement data for the agreed structural locations.
- Structured recording of measurements and associated technical observations.
- Technical information supporting structural condition assessment.
- Measurement information suitable for further technical, maintenance or survey review where applicable.
- A documented technical approach consistent with the increasing emphasis on organization, capability, procedures and records for thickness measurement firms.
Independent Technical Approach
PAMS Pacific Admiralty Maritime Services
PAMS Pacific Admiralty Maritime Services provides independent marine surveying, marine technical consultancy, engineering assessment, technical inspections and maritime compliance services.
For ultrasonic thickness measurement projects, PAMS focuses on objective technical evidence, measurement traceability, structural assessment and professional reporting within the agreed project scope.
The technical approach is independent and does not replace the statutory authority, Administration or classification society responsible for the applicable survey or approval decision.
Frequently Asked Questions
What vessel was involved in the UTM project?
The project involved a 57,850 DWT bulk carrier built in 2018 and attended at Subic Bay, the Philippines.
What technical service was performed?
The project involved ultrasonic thickness measurement as part of an independent marine technical inspection and vessel structural condition assessment.
What is Ultrasonic Thickness Measurement (UTM)?
Ultrasonic Thickness Measurement (UTM) is a non-destructive testing and measurement method used to determine the remaining thickness of suitable materials, including ship hull plating and marine structural components.
What is UTM used for on ships?
UTM is used to determine the remaining thickness of ship structural components and to support structural condition assessment, corrosion monitoring, classification and statutory survey preparation, dry-docking, repair planning and technical investigations.
What structures can be measured using UTM?
Depending on the inspection scope and accessibility, UTM can be used on hull and shell plating, decks, frames, floors, girders, stiffeners, bulkheads, cargo holds, tanks and other accessible marine structural components.
Are UTM measurements affected by surface condition?
Yes. Surface condition can affect measurement reliability and accessibility. Coatings, corrosion, scale, surface preparation and other physical conditions may need to be considered when planning and performing measurements.
Are UTM measurements affected by accessibility?
Yes. Accessibility can affect the measurement scope, locations and practical execution of UTM. Safe access, structural configuration and surface condition should be considered when establishing measurement coverage.
What is MSC.553(108)?
MSC.553(108) is an IMO resolution adopted on 23 May 2024 that introduces amendments to the 2011 ESP Code concerning procedures for approval and certification of firms engaged in thickness measurement of hull structures of bulk carriers and oil tankers. The amendments entered into force on 1 January 2026.
How does MSC.553(108) affect thickness measurement firms?
Following satisfactory document review, the Administration audits the thickness measurement firm to ascertain that it is duly organized and managed in accordance with the submitted documents and capable of conducting thickness measurement of hull structures.
Can UTM results support classification surveys?
Yes. UTM results can provide objective thickness data that supports classification and statutory survey activities. Acceptance of measurements and reports remains subject to the applicable Administration, classification society and survey requirements.
Which classification societies may be relevant to UTM?
UTM work may be relevant to requirements of classification societies including ABS, DNV, Lloyd's Register and Bureau Veritas, depending on the vessel, class status, survey scope and applicable approval or certification requirements.
Can UTM results support repair planning?
Yes. UTM results provide thickness information that can assist technical teams in evaluating corrosion wastage and structural condition and in planning steel renewal, repairs and maintenance during dry-docking or other technical interventions.
Discuss Your UTM Requirements
PAMS Pacific Admiralty Maritime Services provides independent ultrasonic thickness measurement and marine technical consultancy for vessels and marine structures. Contact PAMS to discuss your vessel, inspection scope or technical requirement.