Spirotherm 20-386-9 Leeb D Hardness Test Block 55-59 Hrc

Product Description

The SPIROTHERM 20-386-9 is a Leeb D scale hardness calibration test block rated for the high hardness range of 55 to 59 HRC. It is used to verify and calibrate Leeb-type portable hardness testers before and during field or shop testing operations. The block measures 3.56 inches in length, 2.16 inches in height, and 1 inch in width, with a total weight of 3 pounds. Calibration blocks of this type are essential quality-control tools for technicians and inspectors who need confirmed accuracy from rebound hardness instruments on hardened steel components.

This test block is suited for use in manufacturing, maintenance, and inspection environments where portable Leeb D hardness testers are employed to assess material hardness on finished or in-process parts. The high hardness range designation makes it appropriate for verifying instrument response on hardened tool steels, bearing surfaces, and similarly treated metals. It is typically used by quality control technicians, metallurgical inspectors, and maintenance engineers working in industrial or fabrication settings.

Key Features

• Leeb D scale configuration matches the most common portable rebound hardness tester probe type
• High hardness range of 55 to 59 HRC for calibration on hardened steel applications
• Compact block form factor at 3.56 x 2.16 x 1 inches for bench or field use
• Single-unit packaging with a minimum order quantity of 1
• 3-pound block mass provides stable, repeatable test surface response

Compatibility

Designed for use with Leeb D probe-type portable hardness testers requiring a high-range HRC calibration reference block.

Installation Notes

Calibration test blocks do not require installation but should be handled and stored according to the instrument manufacturer guidelines to preserve surface integrity. The test surface must be kept clean and free of oil, debris, and oxidation before each use. Never use a damaged or heavily indented block surface for calibration, as repeated impacts in the same location will degrade accuracy over time. Follow the applicable instrument calibration procedure and relevant quality management standards when verifying hardness tester performance.