In rock mechanics, The Type N Original Schmidt (TR-0563 is commonly used for the classification of rock cores and brittle rock.
TR-0563 Type N Hammer is a portable and relatively inexpensive instrument for measuring the surface hardness of rock. The hammer can be used efficiently in both laboratory and field settings.
The mechanism of operation is simple; a hammer, released indirectly from a spring, impacts against the rocks surface through a plunger and the rebound is read on a scale. The compressive strength is then read directly from the curve ranging from 10 to 70 MPa (1,450 to 10,152 psi).
The type N hammer is used on NX or larger core specimens or block specimens having an edge length of at least 6 cm.
TC-3040 Calibration Anvil, manufactured from a special steel alloy, is used for the calibration of test hammers.
- ASTM D 5873