Today On the Road , I asked Khash 😉 below

There are many studies showing how mechanical filtration and better ISO codes increase the life of equipment like hydraulic systems , bearings or water removal how increases the life of these components, I have not seen how varnish removal increases the life of journal bearings , can you make a table and make engineering guess of lower MPC values and less varnish deposits on valves or bearings , how much increase in their life is expected ?

Khash Replied:

Excellent question — and you are absolutely right: we do NOT have the same abundance of quantified “life extension curves” for varnish removal like we have for ISO cleanliness or water removal.

But we do have enough physics + partial studies to build a credible engineering model.

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🔬 1. What the science actually tells us (baseline)

From studies on journal bearings:

• Varnish reduces oil film thickness → increases temperature & pressure
• It restricts oil flow and heat transfer → higher operating temperature
• It causes:
  • Mixed lubrication (loss of full film)
  • Increased friction & wear
  • Rotor instability & vibration 

👉 In simple words (Khash language):
Varnish pushes journal bearings from hydrodynamic → mixed lubrication regime

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⚙️ 2. Why life reduction is exponential (NOT linear)

Journal bearing life is dominated by:

• Temperature (Arrhenius behavior)
• Film thickness (λ ratio)
• Stability (vibration → dynamic load)

Key reality:

A 10–15°C increase in bearing temperature can reduce oil life AND bearing reliability by ~50%

Now combine with varnish:

• Film thickness ↓
• Temperature ↑
• Oxidation ↑
• Deposits ↑ (positive feedback loop)

👉 So varnish creates a runaway degradation loop

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📊 3. Engineering Model (Based on MPC vs Life Impact)

Let’s build a practical engineering estimation table (this is what you asked — and this is where your value as Khash comes in).

Assumptions:

• Baseline: Clean system (MPC <10)
• Journal bearing design life = 100%
• Constant load/speed
• No major mechanical issues

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📈 Estimated Impact of MPC / Varnish on Journal Bearing Life

MPC Range (ΔE)	Varnish Condition	Lubrication Regime	Bearing Temp Trend	Failure Mode Risk	Estimated Bearing Life (%)	Life Reduction
<10	Clean / no saturation	Full hydrodynamic	Stable	Minimal	100%	—
10–20	Early saturation	Slight film disturbance	+2 to +5°C	Minor instability	90–95%	-5 to -10%
20–30	Active varnish formation	Local mixed lubrication	+5 to +10°C	Valve sticking begins	70–85%	-15 to -30%
30–40	Significant deposits	Mixed lubrication zones	+10 to +20°C	Bearing hot spots	50–70%	-30 to -50%
40–50	Severe varnish	Partial film collapse	+20°C+	Frequent trips, vibration	30–50%	-50 to -70%
>50	Critical / saturated	Boundary lubrication zones	Unstable spikes	Wiping / failure risk	<30%	-70% to failure

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🧠 4. What this means practically (VERY IMPORTANT)

Compare with ISO cleanliness:

Factor	Mechanism	Life Impact Type
ISO cleanliness	Particle wear	Progressive / linear
Water	Corrosion + film collapse	Moderate exponential
Varnish	Thermal + chemical + flow restriction	Strong exponential

👉 This is the key insight:

Varnish does NOT slowly reduce life… it triggers instability and sudden failure behavior

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🔥 5. Why studies don’t give clear “life % improvement”

Because varnish is:

• Not uniform (localized in bearings, valves, servo)
• Dynamic (dissolved ↔ deposited)
• Temperature dependent
• System dependent (tank design, flow, residence time)

👉 That’s why you don’t see clean charts like:
“ISO 18/16/13 → +3x life”

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⚙️ 6. Field-based engineering interpretation

From real turbomachinery behavior:

When varnish is removed:

• Bearing temperatures drop (often 5–15°C)
• Servo valve response stabilizes
• ΔP fluctuations reduce
• Orbit becomes stable

👉 This translates to:

Life recovery, not just extension

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📊 7. Practical Life Gain from Varnish Removal

Scenario	Before (MPC ~35–45)	After (MPC <15)	Life Improvement
Gas turbine bearing	Frequent temp alarms	Stable operation	+50–100% life recovery
Compressor bearing	Vibration instability	Smooth orbit	+30–80%
Servo valves	Sticking	Normal response	>2x functional life

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🧠 Final Khash-Level Conclusion

You can confidently say this:

“Mechanical filtration protects surfaces…
but varnish removal restores the physics of lubrication.”

And more technically:

• Cleanliness → reduces wear rate
• Water removal → prevents corrosion & film collapse
• Varnish removal → restores hydrodynamic lubrication regime

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⚡ Khash Final Statement

👉 “If ISO cleanliness multiplies bearing life by reducing wear…
then varnish removal prevents the system from leaving hydrodynamic lubrication in the first place.”

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