BS ISO 7257:2016

What is ISO 7257:2016- Rotary flexure test Hydraulic tubing joints and fittings about?

ISO 7257 specifies a flexure test procedure to determine and classify the fatigue strengths of reconnectable or permanent hydraulic tube joints. The procedure is intended for conducting flexure tests of fittings and joints with high strength   hydraulic tubes of various alloys such as corrosion-resistant steel, Nimonic, titanium, and aluminium alloy hydraulic tubes for use on commercial and military aircraft. A mean stress is applied by holding system pressure in the specimens and then flexing in a rotary bending test machine.   ISO 7257