Squeeze Tools for Plastic Pipe
Squeezing pipe to close off fluid flow is a common procedure used, for the most part, in emergency situations but there are occasions when pipe may be squeezed to allow downstream connections or for repair and maintenance. On the emergency side, damaged pipe sections can be quickly isolated using this procedure while maintenance crews conduct their repair work. Upon completion, the pipe may be re-rounded to once again allow the free flow of fluid back through the pipe.
Care must be taken when squeezing plastic pipe as standard procedure allows for a maximum squeezing ratio of 80%. If exceeded, the possibility of pipe damage increases dramatically until a 100% squeeze virtually ensures a reduction in hydrostatic performance after the clamp load is released. In addition, the distance from the squeezed region to the nearest connection or another squeezed area should exceed five times the external pipe diameter.
In light of the above, a complete stoppage of fluid flow will not, and should not, be attempted or achieved. It is only reduced to a rate that does not endanger the work area and maintenance crew.
A successful squeeze-off depends on a combination of factors including;
- pipe material being used
- design of the tool being used
- procedure being followed by the maintenance crew
- pipe diameter and wall thickness
Following is a list of specifications that relate to pipe squeezing and pipe squeeze tools.
- ASTM F1041-02(2008) Standard Guide for Squeeze-Off of Polyolefin Gas Pressure Pipe and Tubing
- ASTM F1563-01(2007) Standard specification for Tools to Squeeze-off Polyethylene (PE) Gas Pipe or Tubing
- ASTM F1734-03(2009) Standard Practice for Qualification of a Combination of Squeeze Tool, Pipe, and Squeeze-Off Procedures to Avoid Long-Term Damage in Polyethylene (PE) Gas Pipe
Another excellent source for information on squeezing plastic (PE) pipe may be found at the Performance Pipe web site.
Technical Note PP 801-TN - Polyethylene Pipe Squeeze-Off
