How Often to Check Vibration — and When That Check Should Become a Balance Job

設定正確的監測間隔

沒有通用的排程。「每月」並非總是正確，「每季」並非總是錯誤。正確的間隔取決於一件事： 故障從首次可偵測症狀發展到功能性失效的速度有多快？ ISO 17359 calls this the "lead time to failure."

規則很簡單：測量間隔應短於失效前導時間的一半。如果軸承通常從首次剝落到卡死需要兩個月，則至少每月測量一次。如果風機葉輪積塵導致振動偏移只需三週，則每 10 天檢查一次。半間隔規則確保您在故障發展視窗內至少獲得兩個數據點——足以觀察趨勢並在失效前規劃行動。

基於風險的間隔選擇

ISO 17359 requires a criticality and risk audit before choosing intervals, but it does not prescribe numbers. The intervals below are our field defaults, built on that framework — start there and adjust as your own trending data shows how fast faults actually develop.

這些只是起點。一旦偵測到變化——振動水平緩慢上升、頻譜中出現新頻率——請立即增加測量頻率。一台原本「每季」檢查的機器，在顯示出發展中故障的那一刻，就變成「每週」檢查。

連續監測與定期監測：兩種方法，同一目標

大多數工廠同時使用這兩種方法。關鍵資產配備線上系統，其他設備則使用便攜式儀器進行定期巡檢。關鍵在於將方法與關鍵性及故障發展速度相匹配——而不是為整個工廠選擇單一方法。

For periodic routes, the Balanset-1A has a built-in Route Inspection mode (F9 in the software): define your measurement points once, walk the round, and the software stores every reading and plots the overall RMS trend by date with ISO 10816 zone bands, plus separate trends for the 1× and 2× harmonics. Comparing each reading to the baseline and to previous rounds happens in the chart, not on paper.

振動趨勢分析：追蹤什麼以及如何追蹤

收集數據卻不追蹤隨時間的變化是沒有意義的。振動趨勢分析意味著將每次讀數與基線及先前讀數進行比較——以觀察機器是變好、變壞還是保持不變。

建立基線

每台機器都需要一個參考點。在穩定且可記錄的條件下記錄基線振動：穩定轉速、正常負載、穩定溫度。對於新機器，在調試完成後進行測量。大修後，請允許短暫的磨合期（24–72 小時）再鎖定基線——在軸承就位和組件沉降的磨合過程中，振動可能會發生變化。

將運轉條件與振動資料一併記錄。沒有轉速、負載和溫度背景的振動讀數幾乎毫無用處——您無法比較在 60% 負載下取得的讀數與在 100% 負載下取得的讀數。

追蹤項目：三個層級

第一層 — 整體 RMS 速度（mm/s）。 The simplest and fastest check. Compare to ISO 10816 zone boundaries (see table below; the ISO 10816 series has been superseded by the ISO 20816 series — the zone values are unchanged). A single number that tells you "good, acceptable, investigate, or act now." Use this for route efficiency — it takes 30 seconds per measurement point.

第二層 — 關鍵頻率成分。 當整體水平上升時，您需要了解 為何. Track the 1× RPM component (unbalance, looseness, buildup) and the 2× RPM component (misalignment, coupling). The Balanset-1A measures vibration velocity in the 5–1000 Hz band (its sensor response rolls off above roughly 550 Hz), so its FFT spectrum resolves the 1× component, its harmonics, and bearing tones that fall below 1000 Hz. Early-stage rolling-element bearing defects develop in a much higher frequency band and normally require envelope (demodulation) analysis, which the Balanset-1A does not provide — use it to catch unbalance, misalignment, and looseness, and a dedicated bearing analyzer for early bearing diagnostics.

第三層 — 變化率。 增長率與絕對水平同樣重要。一台穩定運行 12 個月且振動為 4.5 mm/s 的機器，與三週前為 2.0 mm/s 現在升至 4.5 mm/s 的機器截然不同。快速加速意味著故障迅速發展——應縮短間隔並立即規劃行動。緩慢的線性增長則支持在下一個方便的時間窗口進行計劃性維護。

何時進行重新動平衡校正：4 種基於狀態的觸發條件

動平衡校正不是按日曆執行的任務。不要在没有證據的情況下安排「每 6 個月」或「每年」進行動平衡校正。當資料顯示需要時才進行校正——且僅在您確認不平衡是主要故障時進行。

為何動平衡校正後振動很快又回升

如果動平衡校正後幾天或幾週內振動再次出現，不要再次進行動平衡校正——請進行調查。反覆出現的振動意味著動平衡校正只是在處理症狀，而非根本原因。

轉子髒污。 沉積物移位或剝落，破壞平衡。如果您對髒污的葉輪進行了動平衡校正，校正配重是針對污垢進行補償的。當污垢移動時，配重會成為新的不平衡源。解決方案：在動平衡校正前清潔至裸金屬。

熱變形。 轉子在熱狀態下彎曲或不均勻膨脹，改變質量分佈。在 20°C 繞組溫度下冷態動平衡校正的馬達，在 80°C 時可能會產生嚴重振動。解決方案：在運轉溫度下進行動平衡校正。

配合鬆動。 轉子在軸上移位、輪轂滑動或鍵在啟動和停止過程中鬆動。每次啟動都會略微改變位置，因此平衡也會改變。解決方案：在動平衡校正前修復機械配合。

共振。 運轉轉速接近結構自然頻率會放大微小的殘餘不平衡。由於微小的質量變化（熱膨脹、沉積物移位）被放大，機器似乎需要「不斷重新動平衡校正」。解決方案：改變轉速或修改結構以移動自然頻率——請參閱我們的 vibration isolation guide.

Field Report: 14 Months Without a Rebalance

A food processing plant in Central Europe had four identical 30 kW centrifugal fans on a drying line, each running at 2,920 RPM. The maintenance team was rebalancing all four every 3 months — a technician came in for a full day, balanced each fan, and left. Four campaigns a year, four fans each time: 16 scheduled balance jobs per year.

We set up a monthly monitoring route using the Balanset-1A in vibrometer mode. The first three months of data showed: Fan 1 and Fan 3 were stable at 1.8–2.2 mm/s overall (Zone B — acceptable for long-term operation, no action needed). Fan 2 was climbing slowly — 2.4 → 3.1 → 3.8 mm/s — with a rising 1× component indicating unbalance from product buildup on the impeller blades. Fan 4 had a strong 2× component suggesting coupling misalignment, not unbalance at all.

Result: we balanced Fan 2 (after cleaning) and aligned Fan 4's coupling. Fans 1 and 3 were left untouched. Fourteen months later, Fans 1 and 3 still don't need balancing — they're at 2.0 and 2.3 mm/s respectively.

The savings came from stopping unnecessary work. Two fans didn't need balancing at all. One needed alignment, not balancing. Only one actually had an unbalance problem. Monthly monitoring with a portable instrument cost 30 minutes per round — the data told the team exactly which machine needed what, and when.

ISO 10816 振動嚴重度參考

ISO 10816-3 applies to industrial machines with a rated power above 15 kW and nominal operating speeds between 120 and 15,000 RPM (the often-quoted "up to 50 MW" is the cap of its Group 1 category, not the scope of the standard). The table below shows the zone boundaries for Group 2 machines (15–300 kW) on rigid foundations. Use these as reference thresholds for your trending program. Your plant may set tighter limits based on experience.

Note: the ISO 10816 series has been superseded by the ISO 20816 series; the numerical zone boundaries below are unchanged in ISO 20816-3.

These limits apply to broadband RMS velocity measured on the bearing housings or machine structure in the 10–1000 Hz band (2–1000 Hz for machines running at or below 600 RPM). Do not compare a single narrow-band component — for example the 1× peak — with these zone boundaries; they are overall values.

These values apply to Group 2 machines (15–300 kW) on rigid foundations. For Group 1 (>300 kW) and flexible foundations, thresholds differ — consult the full standard. The key point: Zone A/B = monitor normally. Zone C = investigate and plan. Zone D = act now.

Note that the Route Inspection trend chart on the Balanset-1A draws its zone bands from the ISO 10816-1 machine classes (I–IV), not from the ISO 10816-3 group scheme in the table above — so the zone shown on the screen and the zone from this table can differ for the same reading. Pick one scheme for your plant standard and stay with it.

常見問題