JIS/ISO evaluation standard and bearing vibration diagnosis decision criteria

JIS/ISO vibration evaluation standards and judgement standard 2020 - bearing diagnosis 06 - 30 1 JIS/ISO vibration evaluation standard JIS/ISO standard is widely used in the field of comprehensive judge state of rotating machinery. The current JIS ( Japan standard) JISB0906 annex B of the various types of mechanical frequency of the corresponding temporary benchmark 'for speed RMS in absolute value judgement has explained in detail. Roughly divided into the following four types of measuring object. Type Ⅰ: in normal operation condition, engine and mechanical as part of the whole machine. （ On behalf of the case: general motor output under 15 kw) Medium-sized machinery vibration type Ⅱ: no special base [ Output in 15 kw to 75 kw motor] And in special pedestal mounted in the engine or mechanical ( Below 300 kw) Type Ⅲ: large motor and large rotating machinery, installed in a strong base or vibration measuring direction is of high rigidity of heavy duty base. Type Ⅳ: large motor and large rotating machinery, installed in the direction of vibration measuring with a soft and rigid base. （ On behalf of case: the output in more than 10 mw turbine generator set of gas turbine) Graph: representative regional boundary value 2 bearing decision criteria, E3 envelope acceleration vibration standard bearing diagnosis adopted the general principles, which envelope acceleration measurement values to set judgment standard. The number in the chart is only applicable to general rules. From the tendency to judge the severity of the measurement result is a very effective method. Level classification ( 一) Level 1 bearing inside diameter: Dia. From 200 to 500 mm, 500 RPM speed: the ( b） Level 2 bearing inside diameter: Dia. 50 to 300 mm, speed: 500 ~ 1800 RPM ( c) Level 3 bearing inside diameter: Dia. 20 ~ 150 mm, speed: 1800 or 3600 RPM to choose, to judge by E3 peak. Shown in the following table, object by measuring the mechanical trunnion, rotational speed to select criterion to determine. （ Source: the home of acoustic vibration)