Products

Standard Strain Discs are used as reference standards in conjunction with the Agr Polariscope to identify and evaluate residual strain in annealed glass containers and similar products.   The Agr Strain Discs are manufactured in accordance with ASTM C-148 requirements for reference standards. 

The Strain Discs set consists of five glass discs.  Each disc has a radially symmetrical stress induced by a special heat-treating process and calibrated to exhibit a specific retardation value.

A proprietary manufacturing process assures radial symmetry and uniformity of retardation at any given radius. The set of discs is especially suitable for providing a means to measure temper of annealed containers in accordance with ASTM Test Method C-148.

Applications

Glass containers, candle ware, glassware and similar products for:

• Determining retardation and temper in annealed containers
• Determining residual stress 
• Observing the direction stresses

 Features

• Black anodized frame for individual discs to eliminate stray reflections
• Swivel-mount permits stacking of one to five discs
• Traceable, certified calibration
• Protective case