[NDT-Inspect]

ASME V is a standard that provides guidelines for the ultrasonic inspection of materials and components. Calibration blocks are used in ultrasonic inspection to ensure that the equipment and techniques used are capable of accurately detecting and measuring the size of defects or imperfections in the material being inspected.

ASME V specifies the use of calibration blocks for the ultrasonic inspection of materials used in the construction of boilers, pressure vessels, and nuclear power plant components. These calibration blocks are typically made of the same material as the component being inspected and contain simulated defects of known size and location.

There are several types of calibration blocks that may be used for the ultrasonic inspection of piping, including:

1. Flat-bottom hole blocks: These blocks contain a single flat-bottom hole of a known size and depth, which can be used to calibrate the equipment and techniques used in ultrasonic inspection.

2. Multi-hole blocks: These blocks contain multiple holes of various sizes and depths, which can be used to calibrate the equipment and techniques used in ultrasonic inspection over a range of defect sizes.

3. Angular offset blocks: These blocks contain a single flat-bottom hole that is offset at an angle from the surface of the block. These blocks can be used to calibrate the equipment and techniques used in ultrasonic inspection for defects that are not perpendicular to the surface of the material.

4. Corner-reflector blocks: These blocks contain a single corner reflector, which is a simulated defect consisting of a small notch or hole located at the corner of the block. These blocks can be used to calibrate the equipment and techniques used in ultrasonic inspection for defects located at the corners of components.

The use of calibration blocks is an important part of the ultrasonic inspection process, as it helps to ensure the accuracy and reliability of the inspection results. Calibration blocks should be used regularly to verify the performance of the inspection equipment and techniques, and any deviations from the specified acceptance criteria should be carefully documented.