Uzani wa jaribio katika kulipuka kwa rotor ni nini?

Uzani wa jaribio (pia unaitwa uzani wa jaribio au uzani wa angalizo) ni uzani unaojulikana unaoshikamana kwa muda kwenye rotor kwa radius inayojulikana wakati wa kulipuka kwa uso mmoja. Kwa kupima mabadiliko ya mitetemo yaliyosababishwa na uzani wa jaribio, chombo cha kulipuka kinakokotoa uzani sahihi wa kusahih kwa kudumu na pembe. Uzani wa jaribio huondolewa baada ya mkutano wa kupima.

Ninajua jinsi gani ya kuchagua kiwango sahihi cha uzani wa jaribio?

Uzani wa jaribio bora unapaswa kuleta mabadiliko ya mitetemo yanayoweza kupimika bila kuoza rotor au vumbi. Mwongozo wa kawaida wa uhandisi ni kutumia 5% hadi 10% ya kutokuwa na ustawa kinachoidhinishwa (kulingana na ISO 21940) kugawanywa na radius ya kusahih. Uzani wa jaribio ambao ni mdogo sana unaweza kutokasaidia kusoma kwa kuaminika; nyingi sana zinaweza kusababisha mitetemo kwa kupita kiasi au hatari za usalama.

Kwa nini kutokea kama uzani wa jaribio ni uzani ambao ni nzito?

Uzani wa jaribio ambao ni nzito kupita kiasi unaweza kusababisha mitetemo ya hatari kwa wakati wa jaribio, licha ya kuweza kuoza vumbi, mihuri, au rotor yenyewe. Inaweza pia kupita zaidi ya safu ya mstari wa hisi za mitetemo, ambayo inasababisha matokeo yasiyosawa ya kulipuka. Kila wakati kuanza na kiwango cha chini kilichokotolewa (5% ya U_per / r) na kuongeza tu ikiwa mabadiliko ya mitetemo hayajatoshi.

Wapi ninapaswa kuweka uzani wa jaribio kwenye rotor?

Weka uzani wa jaribio katika uso wa kusahih — mahali pa axial ambapo uzani wa usawa wa kudumu utaongezwa. Kwa ajili ya msomeko wa radial, shikamana kwa radius ya juu inayopatikana kuwa na chini ya uzani unaotumiwa. Njia za kawaida za kushikamana ni kufunga kwenye shimo linaloandika, kwa kumtumia uzani wa sumaku, au kuweka uzani kwenye uso wa rotor. Hakikisha uzani wa jaribio unashikamana vizuri na hauwezi kumtoka wakati wa mapinduzi.

Kwa nini kutumia 5–10% ya kutokuwa na ustawa kinachoidhinishwa kwa uzani wa jaribio?

Upeo wa 5–10% ni mwongozo wa kawaida wa uhandisi ambao unasimbika mahitaji mawili: uzani wa jaribio lazima uwe uzani ambao unasumbuka kwa kutosha kusambaza mabadiliko ya mitetemo yanayoweza kupimika (uwiano wa sigili kwa kelele), lakini nzito kwa kutosha kuepukana na mitetemo kupita kiasi. Kutumia kutokuwa na ustawa kinachoidhinishwa kama rejeshi hakikisha uzani wa jaribio unasukuma vizuri kwa ajili ya uzani wa rotor, kasi, na kiwango cha usawa.

How much centrifugal force can a trial weight safely create?

A common field-balancing guideline is that the centrifugal force of the trial weight, F = m·r·ω² (mass in kg, radius in m, ω = 2πN/60 in rad/s), should not exceed about 10% of the rotor weight (W = Mr·9.81 N). Higher forces risk bearing damage, sensor overload, or the weight detaching. This calculator caps its recommendation at that 10% force level automatically. The goal of the trial run is a measurable but safe response — typically a 20–30% change in vibration amplitude or a 20–30 degree phase shift.

Zana ya Uhandisi Isiyolipisha

Kikokotoo cha Uzani wa Jaribio kwa Kulipuka kwa Rotor

Calculate the recommended trial weight mass for single-plane rotor balancing using an empirical field formula. Accounts for rotor mass, speed, correction radius, support stiffness, and vibration severity — and automatically caps the result so the trial-weight centrifugal force stays below 10% of the rotor weight.

Empirical Vibromera Method Kamatia la Usaidizi Kiwango cha Vibration 10% Force Cap

Uzani wa Rotor (Mr) (kg)

Kasi ya Rotor (N) (RPM)

Radius ya Ukamataji (Rt) (mm)

Kamatia la Usaidizi (Ksupp) (0.5–5.0)

Kiwango cha Vibration (mm/s RMS)

Quick presets

Results

Uzani wa Jaribio Uliopendekezwa (Mt)

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Trial Weight Centrifugal Force (F)

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Uzani wa Rotor (Mr)

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Radius ya Jaribio (Rt)

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Kamatia la Usaidizi (Ksupp)

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Mgawo wa Mitetemo (Kvib)

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Radius katika cm (Rt)

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Speed Factor (N/100)²

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Fomula ya Uzani wa Jaribio

The trial weight mass is estimated using an empirical field formula (based on Vibromera balancing experience, not derived from ISO 21940) that accounts for support conditions and vibration severity:

Mt — uzani wa jaribio (g)
Mr — uzani wa rotor (g) — ingiza kwa kg, imabadilishwa kuwa gramu ndani
Ksupp — mgawo wa rigidity ya msaada (0.5–5.0)
Kvib — mgawo wa kiwango cha mitetemo (0.5–3.0) — unachukuliwa kutoka kwa mitetemo iliyopimwa kwa mm/s
Rt — radius ya uongezaji wa uzani wa jaribio (cm) — ingiza kwa mm, imabadilishwa kuwa cm ndani
N — kasi ya rotor (RPM)

Mgawo wa Rigidity ya Msaada (Ksupp)

Mgawo huu unazingatia jinsi muundo wa msaada wa mashine unavyoathiri jibu la mitetemo kwa ulinganifu:

Ksupp	Support Type	Maelezo
5.0	Very rigid	Kizuizi kikubwa cha saruji, muundo wa chuma thabiti. Mitetemo hubadilika kidogo na ulinganifu — inahitaji heavier uzani wa jaribio (Ksupp ya juu).
4.0	Rigid	Msingi wa saruji, pedestal thabiti. Kawaida kwa pampu na kompresa kubwa.
2.0–3.0	Medium	Nosiri la kawaida ya viwanda, baseplate juu ya saruji. Hali ya kawaida zaidi kwa mipampu, motors, na mashine ya jumla.
1.0	Flexible	Nosiri la spring, isolators ya mpira. Mashine inatembea kwa uhuru — lighter uzani wa mtihani utoshelevu (Ksupp ya chini).
0.5	Very flexible	Kumimina kwa vyetezo, visomeko vya laini, jigati/msingi wa usawazaji. Jibu la juu la vibration — uzani wa mtihani mwepesi zaidi.

Rule of thumb: Rigid supports (Ksupp = 4–5) “absorb” vibration, so you need a heavier trial weight to produce a measurable change. Flexible supports (Ksupp = 0.5–1) amplify the response, so a lighter trial weight works.

Mgawo wa Kiwango cha Vibration (Kvib)

Mgawo huu unaonyesha uzani wa sasa wa vibration ya mashine kabla ya usawazaji:

Kvib	Kiwango cha Vibration	Condition
0.5	Nzuri (≤ 1 mm/s)	Uendezaji mzuri sana. Tumia uzani wa mtihani mwepesi ili ishara ya vibration iliyopungua tayari isidushwe.
0.8	Nzuri (1–2 mm/s)	Uendezaji mzuri. Marekebisho madogo tu. Uzani wa mtihani mwepesi.
1.0	Inakubalika (2–3 mm/s)	Vibration inayoonekana lakini inakubalika. Kazi ya kawaida ya usawazaji.
1.2	Inakubalika (3–4.5 mm/s)	Uzani wa kati. Hali ya kawaida ya sehemu.
1.5	Maaliko / Kuu (4.5–11 mm/s)	Uzani mkubwa na muhimu. Kesi ya kawaida ya usawazaji wa sehemu — eneo la chaguo-msingi.
2.0	Hatari (11–18 mm/s)	Uzani mkubwa, usawazaji haraka. Uzani wa mtihani mzito OK — vibration tayari iko juu.
2.5	Hatari (18–28 mm/s)	Uzani mkubwa. Uzani wa mtihani mzito unakubali ili kuhakikisha mabadiliko ya vector yanayoweza kukamatwa.
3.0	Uliokithiri (> 28 mm/s)	Vibration ya ukithiri. Chunguza mashine kabla ya usawazaji; bendi ya uzani wa mtihani mzito zaidi.

Kwa Nini Fomula Hii Inafanya Kazi

The formula Mt = Mr × Ksupp × Kvib / (Rt × (N/100)²) captures the key physics:

Heavier rotors haja ya uzani wa jaribio mnene zaidi (linear na Mr)
Higher speeds kutokeza nguvu zaidi ya centrifugal kwa kila gramu, kwa hiyo uzani wa jaribio mdogo unnahitajika (mraba wa inverse wa N)
Larger radius inamaanisha muda zaidi kwa kila gramu, kwa hiyo uzani mdogo unnahitajika (inverse wa Rt)
Msaada Thabiti haja ya uzani zaidi kutengeneza mabadiliko ya mitetemo yanayofichua (Ksupp ya juu = 4–5)
Msaada Lenye Upungufu kuosha jibu, kwa hiyo uzani mdogo unnahitajika (Ksupp ya chini = 0.5–1)
Mitetemo Zaidi Iliyopo inamaanisha usambazaji mkubwa zaidi unaokosekana — uzani wa jaribio kubwa zaidi kwa uwiano (Kvib ya juu)

Centrifugal Force Safety Cap

The empirical formula alone can suggest a mass that is unsafe at speed — especially with high Ksupp and Kvib values. That is why the calculator always checks the centrifugal force the trial weight would generate:

F = m × r × ω² , ω = 2πN / 60

F — centrifugal force of the trial weight (N)
m — trial weight mass (kg)
r — installation radius (m)
ω — angular speed (rad/s), N in RPM

A widely used field-balancing guideline is that this force should not exceed about 10% of the rotor weight (W = Mr × 9.81 N). If the empirical formula suggests a heavier mass, the calculator automatically limits the recommended trial weight to the 10%-of-rotor-weight force level and shows a warning. The centrifugal force of the recommended weight (in newtons and as a percentage of rotor weight) is always displayed in the results.

Mfano wa Vitendo

Mfano — Pengeza Centrifugal

Given: Mr = 111 kg = 111,000 g, N = 1111 RPM, Rt = 111 mm = 11.1 cm, Ksupp = 1.0, Vibration = 11 mm/s → Kvib = 1.5

Step 1: Speed factor: (N/100)² = (1111/100)² = 11.11² = 123.43

Step 2: Denominator: Rt(cm) × (N/100)² = 11.1 × 123.43 = 1,370.1

Step 3: Numerator: Mr(g) × Ksupp × Kvib = 111,000 × 1.0 × 1.5 = 166,500

Step 4: Empirical estimate: Mt = 166,500 / 1,370.1 = 121.5 g

Step 5 — force check: ω = 2π × 1111 / 60 ≈ 116.34 rad/s. For 121.5 g at 0.111 m: F = 0.1215 × 0.111 × 116.34² ≈ 182.6 N — that is ≈ 16.8% of the rotor weight (111 × 9.81 ≈ 1,089 N), above the 10% guideline.

Step 6 — safety cap: Mt(max) = 0.10 × 1,089 / (0.111 × 116.34²) ≈ 0.0725 kg = 72.5 g

Result: Tumia takriban 72 g trial weight at 111 mm radius (capped by the 10% force limit; the raw empirical estimate of 121.5 g would create excessive centrifugal force).

⚠️ Onyo wa Usalama: An excessively heavy trial weight can cause dangerously high vibration. The goal of the trial run is a measurable but safe response — typically a 20–30% change in vibration amplitude or a 20–30° phase shift. Keep the trial-weight centrifugal force below about 10% of the rotor weight (this calculator enforces that limit automatically). If in doubt, start with half the calculated weight and increase gradually. Always ensure the trial weight is securely attached and cannot detach during rotation.

Kulinganisha na Mbinu ya ISO 21940

The classic ISO approach uses balance grade G to calculate permissible unbalance, then takes 5–10% of it (divided by the correction radius) as trial weight. This Vibromera formula is an empirical field shortcut, not an ISO-derived equation; it gives comparable results while directly accounting for real-world conditions (support stiffness and current vibration level) that the ISO method assumes are ideal. The added centrifugal-force cap keeps its recommendations within safe limits even when the machine is already vibrating heavily.