Joining Other than Welding (10)
Criticality: High
Progress: Not Addressed
Score: 40
DOT Relevance: §192.271 – §192.287
Description of Key Area
Subpart F of 49 CFR 192 refers to requirements for joining
materials in pipelines other than by welding. It does not apply to joining
during the manufacture of pipe or pipeline components. Joining by welding is
addressed in subpart E (Welding of Steel in Pipelines, §192.221 to §192.245). Joining, in general, may take place by
welding of steel, or joining of pipes other than steel, such as plastic pipe or
composite pipe. Plastic pipe is joined by fusion. Composite pipe might be
joined by combinations of mechanical joining and some type of fusion.
Discussion of Criticality
It is important that all joining methods used be adequate to
prevent leakage, permeation of hydrogen, or pipe embrittlement.
Discussion of Progress
No information found.
Recommendations
Appropriate joining techniques must be documented and tested for
hydrogen applications. In addition, standards for flange gaskets and other
sealant materials for steel pipe used for hydrogen applications need to be
established. A definition for a qualified joint must be created. Operator
training and qualification must be developed for the joining methods. Standards
for joining (other than by welding) must be established and incorporated by
reference to the federal code.
ASME B31.12 will reference consensus standards that adequately
cover the mechanical joining of pipes in hydrogen service. Performance testing
is required and should be performed to a national standard. System design and
joint design may dictate what can and can not be mechanically joined.
|