Quality Management Issues in Nondestructive Testing

As an effective quality control method in scientific research and production quality assurance activities, non-destructive testing is one of the testing methods to confirm quality and obtain evidence. The correctness of non-destructive testing results depends on the rationality and completeness of the testing process, as well as the skills and emotions of the testers. An effective way to improve the confidence of non-destructive testing is to incorporate non-destructive testing activities into an effective quality management system, strictly follow the relevant quality management system requirements, and make the individuals or departments involved in non-destructive testing management, testing operations and supervision responsible for their own work quality and coordinate work.

In view of several problems existing in non-destructive testing, this paper emphasizes the concept of "customer focus" and strengthens the node control of scientific research and testing implementation process. It also proposes some control methods, hoping that through the implementation of these methods, all employees can work hard around a goal and continuously improve the efficiency, accuracy and technical level of non-destructive testing research and testing implementation.

2 Establishing the “Customer” Perspective

Although the quality management principle always emphasizes the concept of "focusing on customers", its essence is to emphasize the current and future benefits of the organization itself. The organization and the "customer" should be equal. The organization does not unconditionally accept the requirements put forward by the "customer". The degree of acceptance should be a process of mutual discussion and compromise. However, for the requirements that have been accepted, the organization must complete them.

From the perspective of its own current and future benefits, as a department providing testing services, the non-destructive testing room should regard the functional departments and related departments as "customers". Only by recognizing this can we actively and creatively complete various tasks, gradually and consciously transition from non-destructive testing (NDT) and non-destructive inspection (NDI) to non-destructive evaluation (NDE), walk at the forefront of the discipline, and gain full recognition from the functional departments and related departments.

3. Quality control point management of scientific research work

Quantitative management of scientific research projects has always been a difficult problem. Usually, for a relatively large project, the functional department will require the preparation of management documents such as implementation plans, while relatively small projects are controlled by the research room itself. These relatively small projects are usually only controlled in the form of half-year or year-end summaries according to the requirements of the internal management department, so that some projects cannot be completed on time due to various reasons, or the various problems and difficulties encountered are reported during the internal inspection before the project acceptance. At this time, the functional department can no longer take corresponding compensatory measures. In addition, since there is no document record of any communication process, there is no sufficient reason for the extension of the task. Therefore, regardless of the size of the project, planning and implementation plans should be carried out. Quality control points that keep the entire scientific research process under control should be set in the implementation plan to clarify these control points and requirements for easy implementation.

It is very necessary to review the implementation plan in the whole department. The reviewed implementation plan implements the principle of full participation, provides an opportunity for the leaders to create good scientific research conditions for the research team, and keeps the entire scientific research process under control.

4 Control Verification in Production Testing

In non-destructive testing, starting from the discussion requirements and the requirements that must be completed and accepted, the "recipient" column of the test task list and the delivery card must be filled in carefully. The "recipient" often becomes the first or only person to communicate with the "customer" in actual scientific research and production. Therefore, the "recipient" must undergo professional training, must have a full understanding of the equipment, technical status and current testing capabilities of this process, must carefully check the acceptance standards and other requirements of the task list submitted for inspection, and must be obliged to correct any errors instead of mechanically executing them. For the progress requirements that cannot be guaranteed to be completed, it is necessary to negotiate with the task proposer and obtain understanding, and strive to complete the progress that is implemented in writing.

Unit leaders can organize inspection teams to inspect and verify the production inspection situation; inspection and verification work is controlled by nodes; nodes include quality control nodes and progress nodes. An example of a work checklist is shown in Table 1.

The inspection and verification of progress nodes is to check the completion progress of the work. It mainly checks whether the inspection work is carried out according to the planned nodes, whether the adverse factors affecting the progress are actively overcome, and the degree of satisfaction with the progress plan temporarily adjusted by the "customer".

The inspection procedures and inspection schedule are reviewed, approved and released, fully reflecting the technical requirements and schedule requirements of the "customer" for the inspection work. The implementation of the inspection and verification inspection procedures is to check the degree of meeting the "customer" inspection technical requirements; and the completion of the inspection and verification inspection schedule is to check the degree of meeting the "customer" progress requirements.

Nondestructive testing requires statistics on test data for products with large test volumes, especially statistics on the number of products entering and leaving each project, the qualified rate, the number of unqualified product reports, and the test cycle. Statistics on product defect types should also be collected during the required period to facilitate the process department to find problems. Table 2 gives an example of defect statistics for a casting.

It can be seen from Table 2 that the frequency of defects such as pores and underfill is relatively high. The process department can focus on studying corrective measures for these two defects to further improve the product yield.

5. Non-conforming Product Report

At present, when filling out the unqualified product report for the unqualified products detected, the laboratory only describes the unqualified products without filling out any disposal opinions. The development trend of non-destructive testing is to continuously transition from NDT and NDI to NDE. NDE requires non-destructive testing personnel to conduct a comprehensive evaluation of the integrity, reliability and performance of the equipment or components being tested while mastering the load conditions and environmental conditions of the object (such as predicting the safety and life of materials in fracture mechanics). Therefore, non-destructive testing workers should set higher requirements for themselves. It is recommended to attach corresponding disposal suggestions after filling out the unqualified product report; especially for major or single products, based on the experience and knowledge of the testing personnel, considering the load conditions of the workpiece and environmental conditions such as operating conditions, and not sticking to the requirements of technical conditions, put forward their own suggestions, and provide reference for superiors or expert groups to make final disposal decisions.

6 Conclusion

This article emphasizes that in non-destructive testing work, we should firmly establish the concept of regarding functional agencies and relevant departments as "customers"; in scientific research projects, regardless of the size of the project, implementation plans and other documents should be prepared to ensure that quantitative management in scientific research management is implemented; in production testing, specific methods of inspection and defect statistics are proposed to provide a basis for quantitative assessment of employee work and process improvement by process departments.