Non-Destructive Testing of metal tubing for medical and industrial applications

管材通常由一系列连续的拉伸操作制成，其中每一个操作都可能在最终产品中引入缺陷。这些缺陷包括不连续性（例如，拉延线）和尺寸不准确性（可能是壁厚、外径（OD）、内径（ID）、同心度或直线度）。随着管变得越来越小，精确测量这些的难度增加，导致使用管的统计抽样进行破坏性测试。不用说，这是不理想的，导致了完全良好的管的浪费。对这些管的分析问题不是新的，但是由约翰逊万丰公司生产的小规模的管给测试带来了进一步的问题，增加了测试的复杂性。此外，尺寸的范围也提供了其自身的障碍。很可能不会有一个放之四海而皆准的解决办法。尺寸范围还受管的纵横比的影响，每个管的长度可达2米。客户通常会对这段长度进行分段，以便他们能够接触到JM无法接触到的管道区域。因此，该项目的目的是与NPL一起探索使用现有无损检测技术进行测试的增强方法。该项目将首先考虑目前可用的方法，然后选择最有前途的技术。这些将被开发用于JM生产的较小尺寸的组件。最后，衍生技术的可行性将被认为是从制造的角度来看。理想情况下，这些技术将与拉伸工艺一起使用，但如果这证明是不可能的，那么就需要考虑测试将适合生产设施的位置，以及在什么阶段对管进行研究。

Tubes are often made by a series of sequential drawing operations, each of which can introduce defects into the final product. These defects include both discontinuities (e.g draw lines) and dimensional inaccuracies (which can be in wall thickness, outer diameter (OD), inner diameter (ID), concentricity or straightness. As the tubes become smaller, the difficulty in measuring these accurately increases, resulting in the use of statistical sampling of tubes for destructive testing. Needless to say this is not ideal, resulting in the wastage of perfectly good tubes.The problem of analysis of tubes such of these is not new, but the small scale of the tubing produced by Johnson Matthey introduces further problems to the testing, increasing the complexity of the testing. Furthermore, the range of sizes also provides its own obstacles. It is entirely likely that there will not be a one size fits all solution to the problem. The size range is also affected by the aspect ratio of the tubes, with each tube being up to 2 m in length. This length is then often sectioned by customers, giving them access to areas of the tube JM does not have access to.The aim of the project therefore is to explore with the NPL enhanced methods for testing using existing NDT techniques. The project will start by considering the currently available methods, then downselect to the most promising techniques. These will then be developed to function on the smaller sized components produced by JM. Finally, the feasibility of the derived techniques will be considered from a manufacturing viewpoint. Ideally the techniques would be useable inline with the drawing process, but if this proves impossible then consideration will need to be given to where the testing would fit into the production facility, as well as at what stage the tube will be investigated.