Umumiy tebranish darajasi spektrdan qanday hisoblanadi?

The overall (broadband) vibration level is calculated as the root-sum-of-squares (RSS) of individual spectral components: Overall = √(a₁² + a₂² + ... + aₙ²). This applies to RMS amplitudes of individual frequency components.

Crest factor is the ratio of peak value to RMS value. For a pure sine wave, CF = √2 ≈ 1.414. Higher crest factors indicate impulsive events like bearing faults. Normal machinery typically has CF = 2–4; CF > 4 may indicate developing faults.

Tepa (peak) yoki RMS amplitudalaridan foydalanish kerakmi?

Umumiy darajani hisoblash uchun RMS amplitudalaridan foydalaning. Ko'pchilik tebranish analizatorlari spektral chiziqlarni RMS qiymatlari sifatida ko'rsatadi. Agar tepa (peak) qiymatlariga ega bo'lsangiz, yig'ishdan oldin RMS ga o'tkazish uchun √2 ga bo'ling.

Nima uchun umumiy daraja komponentlar yig'indisiga teng emas?

Chunki turli chastotalardagi tebranish komponentlari mustaqil bo'lib, ularning kombinatsiyasi arifmetik yig'indi emas, balki kvadrat ildizlar yig'indisi (RSS) bo'yicha hisoblanadi. RSS usuli turli chastotali komponentlarning statistik mustaqilligini hisobga oladi.

Qanday o'lchov birliklaridan foydalanish kerak?

Har qanday izchil birlik qo'llanilishi mumkin — tezlik uchun mm/s RMS, tezlanish uchun g RMS yoki siljish uchun μm. Asosiy talab: barcha kirish komponentlari bir xil birlik va o'lchov turiga ega bo'lishi kerak (barchasi RMS yoki barchasi peak).

Bepul muhandislik vositasi — #014

Umumiy Tebranish Darajasi Kalkulyatori

Kvadrat ildizlar yig'indisi usuli yordamida spektral komponentlardan umumiy tebranish darajasini hisoblang. Crest-faktor uchun 10 tagacha amplituda qiymatini va ixtiyoriy tepa qiymatini kiriting.

RSS Method Crest Factor 10 tagacha komponent

Results

Umumiy RMS darajasi

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Crest Factor

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Komponentlar soni

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Dominant komponent

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Dominant ulush

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Kvadratlarning ildiz yig'indisi (RSS)

Mustaqil spektral komponentlardan kelib chiqadigan umumiy tebranish darajasi quyidagicha:

Where a_i — alohida spektral komponentlarning RMS amplitudalari.

Crest Factor

CF = √2 ≈ 1.414 — Toza sinus to'lqini
CF = 2–4 — Oddiy mexanizm
CF > 4 — Zarbli hodisalar (podshipnik nuqsonlari)
CF > 6 — Kuchli zarba yoki bo'shashish

Amaliy Misol

Misol — Markazdan qochma nasos

Spektral komponentlar (mm/s RMS): 3.2, 1.8, 0.9, 0.4, 0.2

Overall = √(3.2² + 1.8² + 0.9² + 0.4² + 0.2²) = √(10.24 + 3.24 + 0.81 + 0.16 + 0.04)

Overall = √14.49 = 3.81 mm/s RMS

If peak = 8.5 mm/s → CF = 8.5 / 3.81 = 2.23 (normal)

ℹ️ Note: The dominant component (1×, usually) typically contributes the most to overall level. If one component is much larger than others, the overall ≈ that component’s amplitude.