Curtiss Wright Nuclear
Inspecting HDPE Pipe Butt Welds
Posted:
Source: Evident
High-density polyethylene (HDPE) pipes have been used in infrastructure applications for nearly half a century, initially as water pipes and later in the gas industry. Pipes made of HDPE are reliable and durable, easy to repair, have a long in service life, and convenient to install on site. Installation involves joining the pipes using either electrofusion or hot fusion butt welding.

Today, HDPE pipes are used extensively for a range of applications, including:

  • Natural gas transmission
  • Water supply
  • Sewage
  • Agricultural irrigation
  • Transportation of fine particles in mines
  • Oil fields
  • Chemical industry
  • Telecommunications

As the demand for HDPE pipes continues to grow, the quality of welded joints is also of increasing concern.

For example, under cities where natural gas lines were built using HDPE pipes, there are a multitude of welded joints in these pipeworks. If the integrity of any one of these joints begins to fail, there is a high risk for a gas leak with a potential for explosion. It’s critical to inspect these joints during the construction of HDPE pipeworks to identify and repair any welding defects to eliminate these hidden dangers in advance.

DPE pipes are joined using electrofusion or heat fusion. These fusion methods typically use butt fusion machines that include an alignment jig like the one shown above.

Butt welding polyethylene pipes involves inserting and clamping the two pipe ends in the jig to align them, shaving the ends to make sure they’re flat, heating the ends with a hot plate until molten, and then pressing the ends together using a specified force until a bond forms. The pipe remains in the jig until it properly cools.

Read the full blog article at Evident.

Mistras Group