ERVW® AOD Blocks with EDM Notches

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Watch the ERVW Video with Paul Holloway

PH Tool™ and Holloway NDT have jointly designed and produced a set of three Extended Range Variable Wall (ERVW)® Piping Calibration Blocks.  The first iteration of the ERVW Piping Calibration Blocks was released with Side-drilled Holes as the reference reflector type. Now, PH Tool is pleased to announce that a version with EDM Notches is also available for those who prefer that reflector type over holes. 

Created for calibration in the axial direction for examination of circumferential butt welds, these blocks come in three sizes: small (3” to 5”), medium (6” to 10”) and large (12” to 20”). As a set of three, these blocks are kitted in a protective storage case for transportation to inspection sites, offering convenient calibration on over 96 inspection sizes.

The key to the Extended Range Variable Wall series is the "variable" aspect. Only three blocks are needed to cover a large range of pipe sizes, which would otherwise require dozens of calibration blocks. The small block covers 12 pipe sizes, while the medium block covers 29 sizes. The large size covers a massive 55 inspection sizes on the pipe schedule chart. See the chart above for more information about which ERVW Piping Calibration Block can be used with which pipe sizes. Each step is also engraved with the pipe sizes (OD/wall) covered.

All Notch Blocks Back

The ERVW blocks feature EDM Notches in accordance with T-434.3-1 and -2 for testing circumferential pipe welds. The slanted end cut eliminates corner trap reflections and allows for full DAC/TCG calibrations with conventional ultrasonic testing or phased-array ultrasonic testing. Each block is machine-engraved with a unique serial number and alloy. The surface finish is media-blasted to 125 Ra max to simulate inspection conditions.  The steps were placed on the ID rather than the OD to maximize usefulness of wedge curvature in accordance with the requirements of T-432.2 introduced in 2017. 

If you have questions about our Extended Range Variable Wall (ERVW) Piping Calibration Blocks or would like to place an order, please contact us for a quote. 

Don't need the whole set of three blocks? No problem; we now offer the ERVW® blocks as Singles. Simply specify if you need the Small, Medium, or Large block. 

Looking for Extended Range Variable Wall Piping Calibration Blocks with Side-drilled Holes instead of EDM Notches? Click here to find out more!