Stress Analysis of Pressurized Helical Wound Wire Reinforced Elastomeric Hose Subjected to Large Bending Deformation

Maximum wire stress in helically wound pressurized elastomeric spiraled hose subjected to large flexural bending is mathematically analyzed. Solution approach is to superimpose the state of stress of a straight pressurized hose and an unloaded hose bent to a small radius. Since helical wires during pressurization change both radial position and angle, stresses due to a change of radii of curvature and torsion are included along with axial stress. Bending stress is obtained by decomposing the hose into its basic element, a single helical wire, and applying a pure bending moment to it. Hose bending stiffness is approximated as a summation of the bending stiffness of each wire plus individual bending stiffness of the elastomeric cylinders representing the tube, jacket, and cover, respectively. Bending stiffness test data is provided for both four and six spiraled hose with inside diameters 1.0 and 1.25 inches (25.4 and 31.8 mm).