Working Group on NDT for Heritage Boilers

Groups

The BINDT Working Group on NDT for Heritage Boilers was created as one of the recommendations of the BINDT Workshop on NDT Requirements for Heritage Railway Boilers, held in February 2018, and this was its inaugural workshop/meeting. The group will recommend potential improved NDT methods, NDT training and qualifications, validation methods for NDT techniques and samples required for validation and pre-inspection calibration. The other main recommendation of the requirements workshop was for the Heritage Railway Association (HRA) to form a group for reviewing the HRA boiler codes of practice (guidance notes), including allowables for defect types, safety factors going beyond the original design documents and including more on NDT with input from the BINDT Working Group on NDT for Heritage Boilers.

Working Group Objectives
The objectives of the new group are derived from the report of the BINDT Workshop on NDT Requirements for Heritage Railway Boilers, the report of which is available to download here. The objectives are listed below.

To develop and evaluate potential improved NDT methods for heritage boiler inspection and to make available the outcomes of the evaluations in terms of capabilities and limitations.
To create a recommended practice for ensuring that NDT inspections can be relied upon to accurately reflect the boiler condition, including oversight of NDT training, experience and qualifications.
To create a best practice guidance document for appropriate NDT methods including information to assist in the choice of the most appropriate method.
To make possible the validation and sign-off of NDT written procedures for specific inspections.
To collect, design and manufacture samples required for validation of NDT techniques and calibration blocks for pre-inspection calibration.
To create a central illustrated repository for shared information about failure modes, experiences and NDT inspections on specific boiler types that would future-proof the heritage sector as we lose the first-hand experience.

Requirements Workshop
The following is a summary of the other requirements identified at the requirements workshop:

Define new NDT methods to find small defects in the known problem areas and the surrounding environment. Monitoring of defects should be undertaken.
It is important to use suitably trained NDT operators and a list of those who have the required training, qualifications and experience in each method should be considered.
A review of the HRA guidance notes is required to include NDT and this review should be undertaken by a group that includes the insurers, who agree a process and establish a central repository for sharing experiences of working with boilers of specific types.
It is important to review the defect allowables standards for the heritage sector to encompass these defects, allowing for the long period of generation of defects and the potential for monitoring defects.
A central illustrated repository for shared information about failure modes and NDT inspections on specific boiler types/locomotive types would future proof the heritage sector as we lose the first-hand experience. HRA is to be approached to host this.
Guidance on the advantages and disadvantages of different NDT methods.
Guidance on NDT best practice, where possible, would provide a starting point – a validated NDT solution – allowing the competent person to consider it as their recommended inspection.
Training and certification of in-house staff, for example to NDT ‘Level 1 limited’ just for ultrasonic stay inspection.
Provision of test samples both for validation and for proving the functionality of the equipment at the time of inspection.
A process for validation of the reliability of NDT procedures (techniques) is required.

Links to documents:
Click here to view the report on the BINDT Workshop on NDT for Heritage Railway Boilers, 13 February 2018.
Link to the report on the Inaugural Workshop on NDT for Heritage Railway Boilers, 13 February 2020, will be available soon.