Section III—Operation and Welding Concerns
This section is to be utilized to assist in visual inspection of welded joints performed on
the UF2000 non-contact butt-fusion equipment. The manual outlines common problems to look
for during fusion and how to correct them. The manual also describes a few techniques for
ensuring your tool is performing to manufacturer’s expectations. However, it should be noted that even
the best looking joint can still be a “cold weld” and that inspection can never replace the need for strict
accordance to welding procedures.
Common Concern #1
Poor Alignment:
When a joint is welded without properly being aligned, the joint will not be fully pressure
rated. The amount of the offset will determine the likelihood of a failure.
Solution:
It is recommended that the pipe be aligned, not to exceed an offset of 10% of the wall thickness.
As standard procedure, the UF2000 equipment is provided with the best alignment features of any
tool on the market. It is essential to fully utilize these adjustments during the alignment process.
If the pipe and fittings cannot be aligned, the pipe should be removed and reloaded. If alignment
problems persist, it may be necessary to adjust the tool.
Common Concern #2
Oversized beads:
Joints may appear oversized after the joint has been made. This problem may be from
attempting to preheat the pipe or from welding with incorrect parameters.
Solution:
It is not recommended to preheat pipe. The tool automatically compensates for the outside
temperature. If there is a significant amount of air flow, preheating will not overcome the flow of
air. It is preferred to move the tool or protect it in some fashion against the wind.
If joints appear larger than normal, it may be due to welding at incorrect parameters. Check the
tool setup to ensure you are utilizing the correct outside diameter and wall thickness. If the
problem persists, verify the temperature of the heating element.
Common Concern #3
Non uniform bead:
If a bead appears wavy or notched, it may be due to improper planning or capping of the
material. It is common on the UF2000/2 that joints have a wave in the three areas of the clamp
opening. The size of the wave will vary depending on the diameter size and wall thickness. The
waves will appear most prevalent in 6” and 10” welding. The wave is not significant to the joint
quality and only appears on the outside, not internally. Since weld strength is primarily based on
the material internally and in the pipe wall, the waves are normally not cause for concern, unless there is a
large wave on one side where the bead disappears altogether. If the wave causes the bead on either side to
disappear, the joint should be cut and redone.
Asahi/America, Inc.
UF 2000/1
Page 9 of 1
8
