RodGloc
Mechanical
- Apr 23, 2003
- 1
I am busy reviewing the design of pipe repair clamps that use thin sleeves or skins and operate around 16 bar or 232psi up to DN600 or 24in.
The gauge of the material is approximately 2mm thick or 0.78in.
Normally on pipe couplings one would use Barlows formula for Hoop strength with a safety factor of 50% of Yield Stress as specified in the American Waterworks Association specification on pipe couplings. There the hoop stress is all the way in the barrel or sleeve of the coupling.
Whereas, in a pipe repair clamp the stress is localised at the repair area and acts more or less over the repair area with stress dissipating at a distance away from it. Therefore the stress levels are localised or eccentric to a point in the pipe.
I have thought of using the approach of the "Area Replacement Method" as found in the ASME Pressure Vessel Code, however this is very conservative. This approach is used for placing welded on nozzles in waterworks pipes where a collar or wrapping plate is welded on around the nozzle as a reinforcement. This is stipulated in the American Waterworks Pipe Design Manual M11.
I appreciate some input in the matter
The gauge of the material is approximately 2mm thick or 0.78in.
Normally on pipe couplings one would use Barlows formula for Hoop strength with a safety factor of 50% of Yield Stress as specified in the American Waterworks Association specification on pipe couplings. There the hoop stress is all the way in the barrel or sleeve of the coupling.
Whereas, in a pipe repair clamp the stress is localised at the repair area and acts more or less over the repair area with stress dissipating at a distance away from it. Therefore the stress levels are localised or eccentric to a point in the pipe.
I have thought of using the approach of the "Area Replacement Method" as found in the ASME Pressure Vessel Code, however this is very conservative. This approach is used for placing welded on nozzles in waterworks pipes where a collar or wrapping plate is welded on around the nozzle as a reinforcement. This is stipulated in the American Waterworks Pipe Design Manual M11.
I appreciate some input in the matter
