The striped flexible hose installation shown is incorrect and will probably fail under pressure because the hose will __________. See illustration GS-0064.
• How a twist in a flexible pressure hose changes when the hose pressurizes and tries to straighten/expand • The purpose of the stripe painted along the hose (what does it show the mechanic about alignment and twist?) • The relationship between hose length change under pressure and the security of the end fittings
• Look at the stripe: what does its spiral shape tell you about the internal condition of the hose between the fittings? • When pressure is applied, will the hose tend to get longer or shorter, and how will that affect any existing twist? • Which failure mode in the choices is most consistent with the hose trying to relieve that twist while the fittings hold both ends fixed?
• Focus on the fact that the hose is already installed with a visible twist shown by the stripe • Ask yourself which option involves movement at the fittings rather than rupture of the hose wall itself • Eliminate any options that don’t depend on the hose trying to change length or relieve twist when pressurized
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