According to Section 6.2 of the astm e83 pdf , the verification device must be accurate to 1/4th of the permissible error of the extensometer. A standard micrometer usually works for Class B, but not for Class C.
: The document states it is not a complete commercial purchase specification. It also specifically excludes bonded resistance strain gauges directly glued to a test specimen from being verified with the standard mechanical apparatus mentioned inside the practice. 2. Extensometer Classification Tiers
By 3 PM, Elena’s eyes crossed. She flagged three outliers. The extensometer was drifting. She grabbed the tiny hex keys and adjusted the spring tension—an art, not a science. Another run. Closer. One more adjustment. Within tolerance.
She sighed. ASTM E83 was the holy text of extensometer classification. A 30-page document defining how to rate devices from Class C (for rough plastics) all the way to Class B-1 and B-2 (for metals with extreme sensitivity). The PDF was buried in a labyrinth of shared drives. When she finally opened it, the scan was grainy—a relic from the early 2000s, complete with hand-drawn diagrams of levers and dial gauges from a mechanical age.
ASTM E83 outlines standardized procedures for the of extensometer systems. It is applicable to systems that record values proportional to length changes in both tensile and compressive strain. Key aspects of the standard include: astm e83 pdf
Solution: You flag the instrument as "Verification Expired," run a full verification according to Annex A1 of the PDF, and document that your 50mm gauge length extensometer is still a Class B-1 between 200 µε and 15% strain.
: This is the international equivalent for the calibration of extensometers used in uniaxial testing.
What are you currently using?
ASTM E83-23 outlines the standard practice for verifying and classifying extensometer systems used in materials testing, assigning performance classes from A to C based on measurement accuracy. The standard, which mandates regular, typically annual calibration, covers both contact and optical devices, with the latest revision adding specific requirements for non-contact systems. Official copies of the standard can be purchased directly from the ASTM International Store 分析测试百科网 Verification and Classification of Extensometer Systems1 According to Section 6
Extensometer systems are classified based on the maximum allowable error of the indicated strain and their overall displacement resolution. When a calibration engineer evaluates a system, they assign it one of six distinct classes: Extensometer Class Maximum Error of Indicated Strain Resolution Requirement Typical Application Extremely strict limits Exceptionally high resolution Specialized research, high-precision calibration standards Class B-1 of reading or fixed limit Modulus of elasticity testing for aerospace alloys Class B-2 Slightly higher fixed error allowance Standard metals testing, yield strength ( Rpcap R sub p ) determination Class C Moderate error threshold General tension/compression tests, plastic deformation Class D Higher error threshold High-elongation materials, polymers, elastomers Class E Maximum permissible error tier Broad structural tear/break limits
The standard is also available for purchase from a network of authorized ASTM distributors, such as Intertek Inform, SAI Global, and the Irish Standards shop. When buying from a distributor, it is wise to confirm you are receiving the latest version (E83-25).
Detail the exact manufacturer, model, and serial number of the extensometer system.
To obtain an authorized copy of the document, you should utilize official channels: She flagged three outliers
If you are reading this because you are about to perform a verification, here is the high-level workflow as defined in the official :
The primary goal is to provide a uniform method for verifying the accuracy of extensometer systems, ensuring that strain measurements are traceable to national standards.
(available as ASTM E83-23 RLV or ASTM E83-25 RLV) is particularly useful for those who need to see changes between editions side by side; it shows deletions with strikethroughs and additions with underlining.
: Mandatory data that must be included in a verification report, such as the classification achieved and the temperature at which tests were performed. How to Access or Convert the Text
: Recent revisions, such as the 2023 version, added specific requirements for optical extensometers