Radiographic Testing (RT) Reference Standards


Industrial radiography involves exposing a test object to penetrating radiation so that the radiation passes through the object being inspected and a recording medium placed against the opposite side of that object. As with other NDT methods, it is important to have a way of controlling the quality of the image displayed on the testing equipment to ensure results can be properly interpreted. In RT, this is done through the use of tools called Image Quality Indicators, or "IQIs," sometimes also referred to as penetrameters or "pennies."

PH Tool™ is often called upon to make IQIs and other RT-related reference standards for special testing applications. We are typically involved in situations where extremely small holes or notches are required. Our highly-specialized "micro" machining techniques, and our willingness to produce custom-designed standards makes us a natural choice for these items.

Standard RT Product Offerings From PH Tool:

  • IQI's / Penetrameters in hard-to-find materials and sizes
  • RT Step Wedges and Riser Blocks
  • RT Individual Mounting Blocks or Mounting Block Sets
  • ASTM E2737 Duplex Plate Phantoms
  • ASTM E2737 5-Groove Wedges (Heavy and Light Metals)

Specialized Machining


In situations where conventional drill bits or endmills cannot be used, PH Tool employs specialized EDM (Electrical Discharge Machining) hole and notch machining techniques. The ability to EDM holes allows us to go smaller in diameter (under 0.001" / 25µm,) deeper, (and with less risk of breakage,) than conventional drill bits. Small holes like this are often used for custom IQIs with "actual 1T" holes, and for machining of pin-hole diaphragms in accordance with ASTM E1165.
Shown at right: Custom ASTM E1817 RQIs made from 0.005" thick Inconel foil with 20 small-diameter holes on each piece. Lead letters affixed one end with 1/8" character height.

The images shown below display special EDM electrodes that have been dressed down from a .040" diameter shank to an ultra-small .0007" diameter "business end" at the bottom. A human hair is shown in the image for comparison. An electrode of .0007" diameter creates holes that are .001" in diameter.  Electrodes are dressed right on the same machine that is used to make the holes to ensure excellent concentricity.  The electrode is rotated during machining of these holes to ensure even electrode wear, resulting in a perfectly round hole that is right on-size. 

Tiny FBH 2  Tiny FBH 2 001 dia



Above: Image of a PH Tool "Nano Notch" (lower) 0.0007" (~18µm) wide x 0.0044" (112µm) long compared to a human hair (upper) at 278x magnification. Notches like these can be used for POD studies in RT or other methods.

EDM technology allows us to machine without regard for material hardness or toughness. When creating notches or slots, highly sensitive "low-energy" EDM machines give us an edge in making extremely narrow notches (down to 0.0006" / 15µm in width)

Examples of Custom RT Standards


Top-left: Custom RT Contour Shims with various thickness in carbon steel, Inconel, and Copper-Nickel alloys.

Top-right: ASTM E1647 Contrast Sensitivity Indicators, Copper, Stainless Steel, and Aluminum alloys.

Bottom-left: Custom IQI holder and assembly for digital radiography (DR,) aluminum assembly with Inconel test blocks and IQIs.

Bottom-right: Custom Line Pair Linearity Gauges for digital radiography (DR,) made from Type 304 Stainless Steel

Also available: Test Blocks and Reference Standards made from refractory metals, such as Tungsten, for use as collimators or step wedges.

Do you have any questions regarding our radiography reference standards? Feel free to drop us a line. The non-destructive testing experts at PH Tool welcome all inquiries.