How can the nick break specimens be broken?

The correct answer indicates that nick break specimens can be broken using any of the methods listed, which emphasizes the versatility in the breaking technique. Nick break tests are performed to evaluate the ductility, toughness, and overall quality of welds in pipelines.

When utilizing multiple methods for breaking these specimens, each technique has its rationale. Pulling in a tensile machine ensures controlled conditions and provides precise measurements of the specimen's strength characteristics. Supporting the ends and striking the center allows for a more practical, field-like assessment, simulating real-world conditions where such fractures might occur. Using a hammer can be a quick method to achieve the desired break, particularly in less controlled environments.

Since all these methods are acceptable according to the API 1104 standards, the choice that states any of these methodologies can be employed to break nick break specimens showcases a pragmatic approach to the testing process. This flexibility illustrates that, depending on available resources and testing conditions, different techniques can yield valid results while examining the integrity of welds.