Tebranish Tahlilida Fazani Tushunish
Phase ikki signal orasidagi vaqt munosabatini, aylanuvchi mashinalar bilan ishlashda esa aniqroq aytganda, vibration signalning aylanuvchi val ustidagi qattiq mos nuqtaga nisbatan vaqt holatini tavsiflaydi. Bu savolga javob beradi: where in the rotation the vibration is happening, and it is normally measured in degrees from 0° to 360°, one full revolution of the shaft. If amplitude tells you how much mashina tebranmoqda va frequency tells you how fast, faza sizga ko'rsatadi u qanday harakatlanayotganini — bu aynan bir xil chastotadagi nosozliklarni bir-biridan ajratib turuvchi narsadir.
Aynan shu oxirgi nuqta fazaning nima uchun muhimligini belgilab beradi. Unbalance, misalignment, a bent shaft and looseness hammasi 1× chastotadagi running-speed cho'qqini oshirishi mumkin; faza ko'pincha mashinani demontaj qilmasdan ularni bir-biridan ajratishning yagona yo'lidir.
1. Faza Qanday O'lchanadi
Fazani o'lchash uchun ikkita signal kerak:
- Tebranish signali — mashinaning harakatini kuzatayotgan accelerometer or yaqinlik sensori dan olinadigan asosiy o'lchov.
- Mos signal — har aylanishda bir marta impuls beradigan tachometerdan, belgi har safar sensordan o'tganda toza impuls hosil qilishi uchun aks ettiruvchi lenta yoki kalit uyasiga qaratilgan holda. Funksional jihatdan bu doimiy o'rnatilgan Keyphasor.
The tebranish analizatori then measures the time delay between the reference pulse and the first positive peak of the vibration signal at a chosen frequency — usually 1× running speed — and converts that delay into an angle. A reading of 90°, for instance, means the vibration peak arrives one-quarter of a revolution after the reference mark passes the tachometer. Because the result is tied to a specific frequency, phase is most often quoted alongside the 1× component; the same idea, generalised across the spectrum, is what makes the phase angle kabi grafikllarni qurish uchun asosiy element bo'lib xizmat qiladi, masalan, Bode and Nyquist diagrams.
2. Fazaning Diagnostik Quvvati
Faza shunchaki raqamdan ko'ra ancha ko'proq ma'lumot beradi. Mashinaning turli nuqtalarida, bir xil o'lchov yo'nalishida olingan ko'rsatkichlarni taqqoslash orqali mutaxassis muayyan tashxisni yuqori ishonchlilik bilan tasdiqlashi yoki rad etishi mumkin. Asosiy tamoyil — ikki nuqtani taqqoslashdir: agar ular bir tomonga harakat qilsa together holat ma'lum bir xulosaga ishora qiladi; agar ular qarama-qarshi tomonga harakat qilsa opposition bu boshqa xulosaga ishora qiladi. Quyidagi kichik bo'limlarda klassik sxemalar ko'rib chiqiladi.
Disbalansni tasdiqlash
Pure unbalance gives similar phase readings — typically within about ±30° — when measured in the same radial direction (say, horizontal) at both bearings of a rotor. The whole rotor is being pulled in one direction at one instant by the heavy spot, so the two ends march in step. Comparing horizontal and vertical readings at one bearing adds another clue: genuine unbalance tends to show a roughly 90° difference between them.
Noto'g'ri tekislanishni diagnostika qilish
Faza val disbalansini tasdiqlashning eng ishonchli usullaridan biridir misalignment. Podshipnikning har ikki tomonida aksial faza o'qishlarini oling coupling: a 180° phase shift (±30°) across it is the textbook signature of angular misalignment, showing that as one shaft moves axially out, the other moves in — a pivoting, see-saw motion at the coupling.
Disbalansni egilgan valdan farqlash
Disbalans ham, egilgan val ham bent shaft raise 1× vibration, yet phase tells them apart. Axial phase readings taken at the two ends of the same motor or pump shaft that differ by about 180° indicate a bow: the ends move in opposite axial directions as the bend rotates.
Bo'shashishni yoki yorilgan poydevorni aniqlash
Faza ko'rsatkichlari tartibsiz, beqaror yoki takrorlanmas bo'lsa, mexanik looseness odatda asosiy sabab hisoblanadi. Zond mashina oyog'idan uning tayanch plitasiga yoki tayanch plitasidan poydevorga ko'chirilganda fazaning sezilarli o'zgarishi bo'sh langar boltiga yoki yorilgan poydevorga ishora qiladi — va yetarli darajada mustahkam emasligi haqida ogohlantiradi poydevor qattiqlik.
Rezonansni tasdiqlash
Mashina tezlanayotgan yoki kritik tezlikdan o'tayotgan paytda critical speed, the 1× phase makes a characteristic 90° shift exactly at the resonance cho'qqisi va butun rezonans mintaqasi bo'ylab to'liq 180° siljish kuzatiladi. Ushbu o'zgarishni kuzatish — bu coastdown — majburlovchi muammoga emas, aynan rezonansga ishora qilishini tasdiqlashning ishonchli usuli hisoblanadi.
3. Faza Sxemalari bo'yicha Qisqacha Ma'lumotnoma
| Observation | Ehtimoliy tashxis |
|---|---|
| Ikkala podshipnik bir fazada, bir xil radial yo'nalishda | Unbalance |
| ≈180° across the coupling, axial | Burchakli noto'g'ri tekislash |
| ≈180° across the two ends of one shaft, axial | Egilgan / qiyshaygan val |
| Beqaror, takrorlanmaydigan faza | Mexanik bo'shashish |
| 90° shift at peak, 180° through the region | Rezonans / kritik aylanish tezligi |
Bu qoidalar yo'riqnoma bo'lib, kafolat emas: ta'mirlashga kirishishdan oldin amplituda, spektr shakli va harmonic mazmunini tasdiqlang.
4. Balanslashtirish kaliti sifatidagi faza
Faza quyidagi uchun muqarrar: rotor balancing. 1× faza ko'rsatkichi og'ir nuqtaning mos yozuvlar belgisiga nisbatan burchak joylashuvini to'g'ridan-to'g'ri ko'rsatib, texnikga qayerga og'irlik qo'shish yoki olib tashlash kerakligini aniq aytadi. tuzatish og'irligining. Amalda analizator sinov trial weight o'rnatilishidan oldin va keyin amplituda va fazani qayd etadi hamda yakuniy tuzatishni beruvchi ta'sir koeffitsientlari hisoblash uchun o'zgarishdan foydalanadi. Ikki kanalli ko'chma asbob, masalan, Balanset-1A ish tezligida mashinaning o'z podshipniklarida ushbu amplituda va faza o'lchovlarini amalga oshiradi, so'ngra og'irliklar o'rnatilgandan keyin qoldiq nomuvozanat ni tekshiradi. Tuzatish og'irliklar o'rtasida taqsimlanishi kerak bo'lganda burchakli bo'linishni hisoblash uchun bizning Tebranish faza burchagi kalkulyatori vektor geometriyasini bajaradi.
5. Faza nima uchun to'liq tasvirni yaratadi
Fazasiz, vibrasiya tahlilchisi faqat qisman ma'lumotni ko'radi — amplituda va chastotalarni, lekin konstruksiya har bir aylanishda qanday deformatsiyalanishini tushunmaydi. Faza shu yo'qolgan kontekstni ta'minlab, cho'qqilar ro'yxatini harakat haqida aniq bayonotga aylantiradi va diagnostika ishonchliligini sezilarli darajada oshiradi. Bu mashinaning tebranishini bilish va uning sababini bilish o'rtasidagi farqdir. Shu sababli faza har qanday jiddiy diagnostikaga kiritilishi kerak va joysida balanslashtirishning muzokaraga uchramaydigan asosi hisoblanadi. muvozanatlash.
