The utility model discloses a convenient fast-
assembly retractable grading ring for a field test, which comprises an air bag, a plurality of groups of
metal covers are uniformly arranged on the outer side of the air bag, the plurality of groups of
metal covers are connected with each other through wires, an inflation and deflation port is arranged at the bottom of one side of the inner side of the air bag, and the inflation and deflation port is communicated with the air bag. Six sets of hook-and-loop
fastener connecting assemblies are evenly arranged on the edge of the bottom of the air bag. According to the utility model, through mutual cooperation among the air bag, the
metal cover, the lead and the hook-and-loop
fastener connecting
assembly, when the device is installed, the device can be covered on experimental equipment, the grading ring and the experimental equipment are rapidly and reliably connected through the hook-and-loop
fastener A and the hook-and-loop fastener B, and the connection effect is enhanced through clamping of the clamping groove and the buckle; the installation and maintenance time is greatly shortened, and after the device is installed, the grading ring can inflate and expand the air bag when a product test is carried out in a use state, so that the
diameter of the grading ring meets the
voltage and anti-
corona requirements.