Flexible eddy current testing probe for heat transfer pipe of steam generator of nuclear power plant

Abstract

The invention relates to a flexible eddy current testing probe for a heat transfer pipe of a steam generator of a nuclear power plant. The flexible eddy current testing probe comprises a guide cone, a first petal, a first line groove cover, a skeleton, a coil coiled on the skeleton, a second line groove cover, a second petal, a lantern ring, a first connecting piece, a corrugated pipe, multiple centering rings sleeved on the corrugated pipe, a copper cap, a small-diameter nylon pipe, a second connecting piece and a large-diameter nylon pipe, wherein the guide cone, the first petal and the first line groove cover are connected in series through a first spring; the second line groove cover, the second petal and the lantern ring are connected in series through a second spring; the first connecting piece is fixedly connected with the corrugated pipe; the corrugated pipe is connected with the small-diameter nylon pipe through the copper cap; the small-diameter nylon pipe is docked with the large-diameter nylon pipe through the second connecting piece; the small-diameter nylon is sleeved with multiple beads, and a stainless steel ring is arranged between the beads; and the coil is connected with a cable. According to the invention, flexibility and elasticity of the probe are increased, and the eddy current testing of an elbow with small curvature radius is completed at one time quickly and effectively.

Description

technical field [0001] The invention relates to a flexible probe suitable for eddy current testing of a heat transfer tube of a steam generator of a nuclear power plant. Background technique [0002] The steam generator heat transfer tube is an important part of the pressure-bearing boundary of the primary circuit of the pressurized water reactor nuclear power unit, and it is installed in an inverted U shape in the evaporator. With the increase of the operating time of the evaporator, the heat transfer tube will be degraded due to chemical-mechanical and other mechanisms, including wall thickness reduction, pitting corrosion, intergranular corrosion / stress corrosion cracking, fatigue, wear, etc., which directly threatens the unit The long-term safe and stable operation of the nuclear power plant will take the heat transfer tube as the key inspection object in the annual regular maintenance of the nuclear power plant. The only effective way to inspect the heat transfer tube ...

AI Technical Summary

Problems solved by technology

There are two defects in this method of two inspections. On the one hand, the use of a probe with a smaller coil diameter will reduce the filling factor and lower the detection sensitivity; The equipment will inevitably increase the radiation dose of the inspectors

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