ADA INSTRUMENTS Schmidt Hammer 225, Руководство по эксплуатации

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MEASUREMENT FOUNDATION
Schmidt Hammer 225
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Namely: the length for strike hammer and rod instant of collision when strike tension spring is a free don’t stress state.
Maximum static friction force between pointer slider and shaft, the standard identiied as 0.5-G.SN, pointer-axis does not
allow grease smear. With 0.1-1N’s dynamometer can inspect this requirement.
Rebound values calibrated on steel anvil of hardness as HRC60 ± 2 steel anvil should be Rm = 80 ± 2, the calibrated
should be divided into four directions or rotation at any angles.
Spherical radius exposed strike rod end is 25+1 mm, collisions end with strike hammer as ring plane. Whether Test
Hammer manufacturers, or Test Hammer during use must comply with the above technical requirements, if one does not
meet, then the Test Hammer or repair, or replacement of parts, at last, it should be calibrate on the steel anvil again, and
the rebound values calibrated should be Rm= 80 ± 2.
Nominal kinetic energy of Test Rebound in the following formula:
In formula:
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E—Kinetic energy, J(N.m-kgf.m), 2. 207J-0.225kgf.m
К—Tension spring stiffness, N / m; (785N / m)
L—Tension spring standard stretching length, mm(75mm)
E = KL
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