ERVW® COD Blocks for Longseam Inspection

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Watch the ERVW Video with Paul Holloway

This set of two blocks has been specially designed for situations where ultrasonic examination takes place circumferentially or “around the curve” for applications such as inspection of longseam welds in piping and vessels.  Jointly designed by PH Tool and Holloway NDT, the blocks feature side-drilled hole reflectors positioned within novel compound-curves, each with multiple thickness steps.  The unique design results in a light and compact form factor, with the largest block weighing just over 15 lbs and spanning just 16 ¾”.

Coverage is provided for nominal pipe sizes from 6” to 10” in the small block and 12” to a whopping 56” in the large block.  The compound OD curves and multiple wall thicknesses actually exceed ASME requirements, providing exceptional signal response and measurement accuracy.  Properly managing beam divergence off the ID and stabilizing beam skew due to probe rocking is essential to maintaining a consistent calibration when inspecting lengthwise on curved surfaces. 

The design maintains compliance with the requirements of ASME Sec V Article 4, Fig T-434.3-2 and the use of side-drilled holes as the reference reflector type provide optimal response and ease of use during calibration.

Set Details:

• Small Block (6-10”) is 8 inches long, and weighs 5 lbs.
• Large Block (12-36”) is 16.75 inches long, and weighs 15 lbs. (Technically covers all the way to 56" OD for select sizes! Please inquire to learn more)
• Surface Finish: Media-blasted to 125 Ra to simulate inspection conditions
• Materials: Most commonly requested in carbon or stainless steel, but other alloys available upon request. Carbon steel blocks are electroless nickel-plated for corrosion/wear protection.
• Machine-engraved transducer positioning marks to aid in functionality and maximize signal from SDHs
• Machine-engraved identification text (including unique serial no.)
• Inspection pipe sizes covered by each thickness step also machine-engraved on OD.

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 both blocks in the set? No problem; we now offer the ERVW® blocks as Singles. Simply specify if you need the Small or Large block.