Stress Engineering Services performs material condition assessments on vessels and high temperature plants by extracting small material samples commonly referred to as “small scoop” samples. These samples can be taken at various depths so that minimum wall is not violated and allows for conclusive metallurgical evaluations to be performed without requiring significant weld repairs.
The pneumatically powered scoop sample cutter is secured to a vessel or pipe magnetically, or with fast setting epoxy. A shallow, spherical 1.25 inch diameter disc is sawed out. The cutter is adjusted to make sure the combined thickness of the sample and saw kerf are above ASME minimum wall requirements, so post extraction weld repairs are not necessary. For piping, samples can be removed from pipes as small as 10” and as large as 30”.
Once extracted, the material samples can be used to create metallurgical specimens for detailed evaluation of possible aging mechanisms such as creep, HTHA and various types of cracking. This approach eliminates ambiguity regarding the need for remediation, if necessary.
Stress Engineering is currently developing and validating a range of tests using sub-size specimens cut from small scoop samples in support of remaining life assessments. These include: