PDI Alternative ASME Calibration Blocks

PDI Alternative ASME blocks are manufactured in accordance with the requirements of the Performance Demonstration Initiative (PDI) Procedure No. PDI-UT-1, Rev. C, Fig. 4 (Ferritic) and PDI-UT-2, Rev. C, Fig. 4 (Austenitic).

These cover the generic procedures for the ultrasonic examination of both ferritic and austenitic pipe welds. The blocks offer an economical alternative to fabricating multiple curved calibration blocks (pipe sections) in numerous diameters and wall thicknesses.

The blocks are normally supplied in sets of 3 individual blocks. Materials for each blocks are A516 Grade 70 Steel, 304/304L Stainless Steel, and 316/316L Stainless Steel. Individual blocks of any one alloy are also available.

Overall block dimensions are 2.000" wide x 2.250" tall x 10.000" long. block design consists of steps simulating wall thicknesses measuring 0.500", 1.000", 1.500" and 2.000". Each step contains a .010" wide EDM notch machined across the width of the step at a depth of 10% of wall thickness. 

Scanning surfaces and reflecting surfaces are machined to simulate pipe and plate surfaces of 250 Ra max. finish. Each block is machine-engraved on one side with the Block description, Serial No., Alloy, and Heat No. All blocks are made from ultrasonically inspected, heat number traceable materials.