ADA INSTRUMENTS Schmidt Hammer 225, Руководство по эксплуатации

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Schmidt Hammer 225
MEASUREMENT FOUNDATION
Working principle
Test hammer the stability of technical speciication, reliability, consistency, rebound method for ensuring the accuracy of
testing the compressive strength of concrete is essential.
Therefore, the technical parameters and speciication of test hammer should be standardized. Normal Impact energy is
2. 207N.m of concrete test hammer basic technical speciication are as following:
Normal Impact energy: 2. 207N. m (0. 225kgf. m)
it is main design parameters of the instrument, when the test hammer rebound at level, bomb attack tension spring
stretch length 75mm which has the kinetic energy. Although it can’t directly test Hammer kinetic energy of the instru-
ments, but, through controlling the stiffness and the standard tensile length of tension spring, and related precision of
the parts, may also be to control kinetic energy purposes.
Strike tension spring stiffness: 7.84N (0.80kgf) /cm.
Stiffness for tension spring will directly affect the nominal kinetic energy size of test hammer, usually through the spring
testing machine strict inspecting the technical parameters, but also can be inspect it according to “JJG817-93” standard
stated special spring testing device.
Strike hammer stroke: 75mm (Namely: strike tension spring stretched the
length of the standard).
Generally, depend on assembly and adjusting to ensure the technical requirements. Instrument self-test method: adjust
the bolt length out on the end cover, when the strike hammer shoot out (namely: unhook), the scale mark of pointer
slider and scale 100 mark of rebound value graduation scale is superposition, this time the length out for strike tension
spring should be 75mm.
Working length of strike tension spring: 61.5mm
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