ASME Vacuum Box Certification

Bubble Test

• The bubble test determines whether welds or weak joints might leak or fail under pressure. Air or liquid is run through the pipe or vessel. The pipe or vessel is then put in a vacuum box. Under low pressure or vacuum, leaks create bubbles as air or water seeps through. When the bubbles are seen in the vacuum test, it is clear proof of where a leak occurred and of its severity.

ASME Standards

• The bubble test is outlined in ASME BPVC, Section V, Article 10. The standards for the vacuum box bubble test are outlined in Appendix II. The ASME recommends near-vacuum pressures of 15 psig inside the vacuum box for the bubble test.

Related Standards

• The American Society for Testing and Materials, or ASTM, issues standards for how to perform scientific testing. ASTM E515 is the standard test method for leaks using the bubble emission technique. ASTM E479 is the standard guide for preparation of a leak testing specification. Both of these ASTM standards can be used for setting up a vacuum box for ASME certification of pressure vessels and piping.