Spi 20-383-6 Hardness Calibration Test Block Leeb D

Product Description

The SPI 20-383-6 is a hardness calibration test block designed for verifying and calibrating Leeb D-type hardness testers. It provides a certified reference surface in the high hardness range, covering 55 to 59 HRC, and is used to confirm instrument accuracy before and after testing cycles. The block measures 3.56 inches in length, 2.16 inches in height, and 1 inch in width, and weighs 3 pounds. Calibration technicians, metrologists, and quality control personnel in manufacturing and metalworking environments rely on reference blocks like this to maintain measurement traceability and instrument performance.

This test block is suited for use in industrial calibration labs, machine shops, heat treatment facilities, and quality inspection departments where Leeb rebound hardness testing is part of the inspection workflow. The Leeb D scale is the most common impact device type used with portable hardness testers on ferrous metals and heavy steel components. This block serves as a stable, repeatable reference standard for daily instrument verification routines.

Key Features

• Leeb D scale reference block for portable hardness tester calibration
• Hardness range of 55 to 59 HRC — high hardness classification
• Compact block form factor at 3.56 x 2.16 x 1 inches for bench use
• Single-unit packaging — sold individually (MOQ 1)
• Compatible with Leeb D impact device instruments requiring a high-range reference standard

Compatibility

Designed for use with Leeb D-type portable hardness testers requiring a high-range HRC calibration reference block. Specific instrument compatibility should be confirmed against the tester manufacturer's calibration requirements.

Installation Notes

Calibration test blocks should be handled and stored according to the instrument manufacturer's guidelines to preserve surface integrity. The reference surface must be kept clean and free of debris before each use. Do not use the calibration surface for impact testing beyond normal calibration verification cycles, as repeated impacts can alter the surface hardness over time. Calibration work should be performed by qualified metrology or QC personnel following applicable laboratory procedures.