INTERPOLATED UMBRELLA TYPE EDDY CURRENT PROBE FOR NON-DESTRUCTIVELY TESTING SPIRAL HEAT PIPE IN STEAM GENERATOR

摘要

PURPOSE: A probe is provided to perform a non-destructive test for curved heat pipes as well as a spiral heat pipe of a steam generator by employing eddy currents. CONSTITUTION: A protective cover(12) is connected to a flexible centering member(10) containing a spinner. Plural guide grooves(14) are formed on the side surface of the protective cover for a test coil group to be inserted to the guide grooves. Herein, the test coil group consists of a test coil(18), a support stand(16), a test coil body(32), and a leaf spring(30) moving the support stand up and down. The test coil body includes the support stand connected by a pin(28). The test coil contains an intermediate guide tube(24) and a press roll(22) having a spring(26) on a central shaft under the protective cover. A probe is folded in an umbrella type in an insertion to improve inserting property. The probe is unfolded in a withdrawal to increase fill factor while minimizing friction.