Use of glass-fabric stretch material for a flexible joint of precast pipe sections

Tests of a U-shaped flexible joint connection made of glass-fabric stretch material (glass fabric impregnated with an epoxy-coal tar-Thiokol binder) showed its high sealing properties and reliable work at an internal pressure up to 1.6 MPa.The use of the U-shaped expansion joints substantially reduces the requirements imposed on the accuracy of manufacturing the ends of sections being joined as well as on their alignment during assembly.Fastening of the expansion joint to the ends of the conduit sections being joined is accomplished by bolts with smearing the zone of attachment with a paint-type epoxy composition.The absence of friction surfaces in the expansion joints has a positive effect on their performance.Fabrication of the expansion joint from glass-fabric stretch material is possible under on-site construction conditions. Tests of a U-shaped flexible joint connection made of glass-fabric stretch material (glass fabric impregnated with an epoxy-coal tar-Thiokol binder) showed its high sealing properties and reliable work at an internal pressure up to 1.6 MPa. The use of the U-shaped expansion joints substantially reduces the requirements imposed on the accuracy of manufacturing the ends of sections being joined as well as on their alignment during assembly. Fastening of the expansion joint to the ends of the conduit sections being joined is accomplished by bolts with smearing the zone of attachment with a paint-type epoxy composition. The absence of friction surfaces in the expansion joints has a positive effect on their performance. Fabrication of the expansion joint from glass-fabric stretch material is possible under on-site construction conditions.