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Industrial Lubricating Grease Guide: Types, NLGI & Selection (2026)

2026-03-19

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Quick Navigation: 1. Market Overview · 2. What Is Grease · 3. The 7 Types · 4. NLGI Grades · 5. Selection Framework · 6. Industry Applications · 7. Grease vs. Oil · 8. Over & Under-Greasing · 9. Compatibility & Changeover · 10. Failure Modes · 11. Grease Analysis · 12. Storage & Handling · 13. FAQ · 14. ZTSH Oil Products


1. Why Industrial Grease Matters — Market Context

Global-industrial-grease-market-size-2024-to-2030-growth-forecast-chart

Industrial lubricating grease underpins virtually every rotating, sliding, or oscillating machine in manufacturing, mining, construction, and power generation worldwide. Far from a commodity purchase, grease specification is a precision engineering decision with direct impact on equipment reliability, maintenance budgets, and production uptime.

Three numbers frame the stakes:

The fastest-growing grease segment globally is calcium sulfonate complex, expanding at 9.1% CAGR — twice the overall market average — driven by mining, marine, and offshore demand for its exceptional water resistance. High-temperature greases hold 35% of 2024 market volume and are projected to grow at 6.5% CAGR through 2030.

China’s lubricant exports grew 18.43% year-on-year in 2025. Belt & Road markets — including Southeast Asia, the Middle East, and Latin America — have become core growth destinations for Chinese-manufactured industrial greases. Domestic Chinese brands now hold 35%+ of the domestic market, with quality standards rapidly converging with Western incumbents at significantly lower cost points.


2. What Is Industrial Lubricating Grease?

Industrial-grease-composition-diagram-showing-base-oil-thickener-matrix-and-additive-system

Industrial lubricating grease is a semi-solid lubricant combining three components: a base oil (60–75% by weight), a thickener (5–25%), and a performance additive package (5–20%). Unlike lubricating oil, grease stays in place under centrifugal force, gravity, and pressure — making it the lubricant of choice for sealed bearings, hard-to-reach lubrication points, and equipment that cannot tolerate leakage.

2.1 How Grease Actually Lubricates — The Thixotropic Mechanism

When a bearing surface moves, shear forces cause the thickener matrix to release base oil, forming a thin hydrodynamic film between metal surfaces. When motion stops, the thickener re-absorbs the oil. This reversible behavior — called thixotropy — is why grease provides lubrication even after extended idle periods, making it ideal for stop-start machines and infrequently operated equipment.

Critical insight most B2B buyers miss: The base oil — not the thickener — does the actual lubricating. The thickener is purely a structural carrier. This is why two NLGI 2 greases from different thickener families can have radically different performance in the same bearing.

2.2 The Three Components — What B2B Buyers Must Verify

Base Oil (the lubricant — 60–75% by weight) Carries out the actual lubrication. Must be matched to operating speed and temperature using ISO VG viscosity classification. Most greases use mineral oil (API Group I–III); specialty greases use synthetic base oils (PAO, ester, silicone) for extreme-temperature or extended-life applications.

Thickener (the structural sponge — 5–25% by weight) Defines temperature range, water resistance, and compatibility with other greases. This is the #1 factor differentiating grease types — and the #1 source of incompatibility disasters when greases are mixed.

Additives (the performance enhancers — 5–20% by weight) Provide extreme-pressure (EP) protection, anti-wear (AW) properties, oxidation resistance, rust inhibition, and tackiness. EP additives are NOT universal — they can damage lightly loaded high-speed bearings by chemical activity at operating temperature.

2.3 Why Grease Is Preferred Over Oil in Industrial Settings

  • Stays in place without a reservoir or pump for many applications
  • Acts as a contamination barrier, sealing against water, dust, and particles
  • Effective at lubrication points subjected to oscillating or vibrating motion
  • Suitable for vertical shaft orientations where oil would drain away
  • Long relubrication intervals reduce maintenance frequency and labor costs
  • Lower system cost — simpler housings, no seals, pumps, or reservoirs required

3. The 7 Types of Industrial Grease — Full Comparison

Thickener chemistry is the primary differentiator between grease families. Selecting the wrong thickener — even with correct base oil viscosity — is a common and costly error.

Industrial Grease Type Comparison Table

Grease TypeTemp RangeWater ResistanceSpeed SuitabilityMixing RiskBest Applications
Lithium Complex (Li-X) ★−30°C to 180°CGoodLow–HighLow (with Li)Bearings, chassis, OEM general-purpose
Polyurea (PU)−30°C to 180°CVery GoodHigh — ideal for motorsHIGH — never mixElectric motors, sealed-for-life bearings
Calcium Sulfonate Complex−20°C to 180°COutstandingLow–MediumModerateMining, offshore, marine, wet environments
Bentone / ClayNo drop point (>230°C base oil limit)ModerateLow–MediumCompatible with mostFurnace, kiln, continuous casters
Simple Lithium (Li)−30°C to 130°CModerateLow–HighLowBudget / general purpose, chassis grease
Calcium (Ca)−20°C to 80°CSuperiorLow–MediumModerateMarine, wet/outdoor, steel works
PTFE / Synthetic−50°C to 260°CGoodHighLowFood-grade, clean-room, extreme temp

3.1 Lithium Complex — The B2B Workhorse

Lithium complex (Li-X) greases are the most specified grease type in general industrial applications. The complexing agent raises the dropping point above 260°C and delivers superior EP performance compared to simple lithium. For OEM and MRO buyers wanting a single approved grease for 70–80% of application points, a Lithium Complex NLGI 2 EP with ISO VG 100–220 base oil is the industry benchmark.

Simple lithium (Li) greases are lower cost but should not be used above 120°C continuous or in heavily loaded applications — the dropping point of ~185°C provides insufficient safety margin for many industrial environments.

3.2 Polyurea — The Premium Choice for Electric Motors

Polyurea (diurea/tetraurea) greases lack metallic soap thickeners, delivering outstanding oxidation stability, high dropping points (>260°C), and compatibility with sealed high-speed bearings. Their clean-burning chemistry generates minimal residue, extending bearing service life dramatically. ASTM D3336 testing on premium polyurea NLGI 2 greases shows 10,000+ hours of bearing life at 125°C.

VFD-driven motors require extra attention: Variable-frequency drives introduce electrical discharge through bearings (EDM bearing damage), visible as gray or black frosted raceways. Specify greases with anti-static or conductive additives for variable-frequency drive applications.

⚠️ Critical Compatibility Warning: Polyurea greases are incompatible with the majority of soap-based greases including lithium, lithium complex, and calcium. Mixing polyurea with lithium grease in a bearing housing can cause catastrophic softening within hours of startup. NEVER switch to polyurea without a complete bearing purge procedure.

3.3 High-Temperature Greases — Bentone, Ca-Sulfonate & Synthetic Options

Applications exceeding 150°C continuous operating temperature demand specific formulations:

Bentone (Clay) Grease: Inorganic clay thickener with no dropping point — it will not melt at any temperature. Base oil oxidizes above ~230°C, setting the true performance limit. Best for kiln car bearings, furnace chain lubrication, and glass processing.

Calcium Sulfonate Complex: The fastest-growing premium grease category globally (+9.1% CAGR). Outstanding water resistance — withstands direct water washout better than any other thickener. Excellent EP performance. Stable to 180°C. The dominant choice for mining, offshore, and heavy construction.

Synthetic Grease (PAO / PFPE / Silicone base): For the most extreme applications — continuous temperatures from −50°C to +260°C, food-processing lines requiring NSF H1 compliance, or clean-room environments where hydrocarbon contamination is prohibited.


4. NLGI Consistency Grades — The Complete Selector {#4}

The NLGI consistency grade — measured by ASTM D217 worked penetration at 25°C — classifies grease stiffness from 000 (semi-fluid) to 6 (block grease). It is the most universally referenced grease parameter, but also the most widely misunderstood.

NLGI Grade Reference Table

NLGI GradeConsistencyTexture AnalogyTypical UseKey Advantage
000–00Semi-fluidVery soft / flowable pasteCentralized auto-lube systems, enclosed gearsMaximum pumpability
0–1SoftSoft butter / shorteningCold-climate bearings, low-temp chainsGood pump delivery at sub-zero
2 ★Medium (industry standard)Peanut butterGeneral industrial: bearings, motors, chassisBalances pumpability & retention
3FirmHard butterHigh-speed, precision, electric motor bearingsBetter channeling, less churning
4–6Hard / blockWax or harderOpen gears, extreme vibration, kiln bearingsStays put under shock & gravity

4.1 DN Speed Factor & NLGI Grade Selection

DN = RPM × bore diameter (mm). Higher DN requires stiffer greases to promote channeling and prevent churning:

  • DN < 75,000: NLGI 1–2 generally appropriate
  • DN 75,000–300,000: NLGI 2–3, channeling behavior preferred
  • DN > 300,000: NLGI 3–4, or consult bearing OEM specification

4.2 The Temperature-Interval Rule Every Maintenance Manager Must Know

Bearing grease service life halves for every 10°C (18°F) increase in operating temperature above 70°C.

If your calculated relubrication interval is 1,000 hours at 70°C: → 500 hours at 80°C → 250 hours at 90°C → 125 hours at 100°C

This exponential degradation is why selecting a grease with genuine thermal stability — not just a high dropping point on the datasheet — is critical for hot applications.


5. How to Choose the Right Industrial Grease — 6-Factor Framework

Grease selection by brand familiarity or inertia (“the last grease that worked”) costs industry hundreds of millions of dollars annually in premature bearing failures. The following systematic framework eliminates the most common selection errors.

Quick Reference: Application-to-Grease Selector

ApplicationTemp RangeNLGI GradeRecommended GreaseCritical Note
Electric motor bearings−30 to 180°CNLGI 2–3PolyureaNo EP additives for ball bearings
Mining / crushing equipment−10 to 150°CNLGI 1–2Ca-Sulfonate ComplexWater washout resistance critical
Steel mill rolling mills50 to 200°CNLGI 2Li-X or Ca-SulfonateISO VG 220–460 base oil
Wind turbine main shaft−30 to 80°CNLGI 1–2Li-X Synthetic PAO5-year interval; fretting resistance
Food processing−10 to 120°CNLGI 1–2PTFE / Al-Complex NSF H1Must carry NSF H1 registration
Construction pin joints−20 to 60°CNLGI 1–2 EPLi-X with tackifierAnti-fretting grade for oscillating motion
Centralized auto-lube−20 to 60°CNLGI 00–1Li-X or Ca-SulfonatePumpability at minimum ambient temp
Kiln / furnace bearings150–300°C+NLGI 1–2Bentone / PTFE SyntheticBase oil oxidizes above ~230°C

Factor 1: Operating Temperature Range

Map the full temperature envelope: minimum ambient start-up temperature AND maximum continuous operating temperature. The grease’s dropping point must exceed max operating temperature by a ≥50°C safety margin. For wide seasonal swings (e.g., outdoor equipment from −20°C to +80°C), synthetic base oil greases provide better low-temperature pumpability without sacrificing high-temperature film strength.

Factor 2: Speed (DN or NDm Factor)

Higher bearing speeds require lower base oil viscosity (to reduce fluid friction) but higher NLGI grade (to promote channeling). The NDm factor — using pitch circle diameter rather than bore — is more accurate for large bearings.

Factor 3: Load and Shock Loading

High loads and shock loading require EP additives (sulfur-phosphorus or MoS₂). However: lightly loaded, high-speed ball bearings do NOT benefit from EP additives and can suffer increased wear from chemical activity at operating temperature. Match EP level to actual contact stress — not just application type.

Factor 4: Water and Contamination Exposure

For equipment exposed to water spray, steam, condensation, or immersion: prioritize water washout resistance (ASTM D1264) and rust inhibition (ASTM D1743). Calcium sulfonate complex and calcium-based greases lead here. In dusty environments such as mining, cement, and quarrying, higher base oil viscosity and tackifying additives help the grease film resist abrasive wear.

Factor 5: Lubrication Method and Fill Volume

Centralized lubrication systems require NLGI 0–1 for pumpability. Manual or single-point application can use NLGI 2–3. For electric motor bearings, fill volume matters as much as grease type — overfilling is the leading cause of motor bearing failure by churning-induced temperature rise.

Factor 6: Compatibility With Existing Grease

The most overlooked factor in practice. When switching grease types or during maintenance, mixing incompatible greases can cause catastrophic softening or hardening, loss of EP performance, and accelerated bearing failure within hours. Always consult the compatibility matrix in Section 9 before introducing any new grease into equipment with residual grease of a different thickener chemistry.


6. Industrial Grease Applications by Sector

Grease-vs-lubricating-oil-selection-decision-flowchart-for-industrial-bearing-applications

6.1 Mining & Quarrying — The Most Demanding Environment

Mining presents the extreme edge of grease performance requirements: continuous vibration, full water ingress, abrasive contamination, and 250–500+ hour relubrication intervals on remote equipment. A single shovel or crusher bearing failure costs $50,000–$200,000+ in repair, lost production, and logistics.

Dominant specification in modern mining operations: Calcium Sulfonate Complex NLGI 1–2 with EP additives and tackifier.

Key performance requirements:

  • ASTM D1264 water washout <1%
  • Timken OK Load >60 lbs (ASTM D2509)
  • 4-ball weld load >400 kgf (ASTM D2596)
  • Pumpable at −20°C for centralized auto-lube systems

6.2 Steel & Metal Processing

Steel mill rolling mill bearings operate at 120°C+ under very high radial loads at low speeds. Continuous casters require greases that survive steam, scale, and cooling water. Central auto-lube systems on rolling mill lines commonly operate with NLGI 0–1 Lithium Complex greases at ISO VG 220–460.

  • Rolling mill bearings: Li-X or Ca-Sulfonate, NLGI 1–2, ISO VG 220–460
  • Open gear / continuous caster: adhesive synthetic open gear grease, ISO VG 680–1500
  • High-temp zones (reheat furnace): Bentone NLGI 1–2 or Ca-Sulfonate

6.3 Electric Motor Bearings — The Highest-Volume Application

Electric motor bearings represent the largest grease application point count in any industrial plant. The industry standard has shifted toward polyurea over the past decade, driven by superior sealed-bearing compatibility and extended service intervals at 160–180°C.

  • Standard motors: Polyurea NLGI 2–3, ISO VG 46–100 base oil
  • VFD-driven motors: Polyurea with anti-static additives — standard polyurea is insufficient for EDM current discharge protection
  • High-temperature motors (>150°C housing): Polyurea with synthetic base oil, dropping point >260°C

6.4 Wind Energy — The 5-Year Interval Challenge

Wind turbine pitch and yaw bearings undergo oscillating motion rather than continuous rotation — a demanding condition where many standard greases exhibit fretting wear (micro-scale adhesive damage under oscillation without full hydrodynamic film formation).

  • Pitch & yaw bearings: oscillation-specific grade with ASTM D4170 fretting wear test compliance
  • Main shaft: Li-X PAO synthetic, NLGI 1–2, ISO VG 460–1500, designed for >5-year service
  • Gearbox bearings: synthetic PAO-based for extended drain intervalshttps://www.nlgi.org/grease-in-wind-turbines/】

6.5 Food & Beverage Processing — NSF H1 Registration Is Non-Negotiable

Any lubrication point with incidental food contact requires NSF H1 registered lubricants. This is a regulatory requirement in virtually every jurisdiction — using non-registered lubricants in food plants constitutes a compliance violation. “Food-grade” labeling alone without an NSF H1 registration number is insufficient.

  • Required: NSF H1 registration (verify the actual registration number at www.nsf.org)
  • Chemistry: Aluminum complex, PTFE, or calcium-based with white mineral oil or PAO base
  • Avoid: Any grease containing molybdenum disulfide, graphite, or heavy metals
  • Additional certifications: Kosher/Halal required for certain customers in Middle East and Jewish markets

6.6 Construction Equipment

Construction equipment greasing covers pin joints, bucket bushings, track chain, swing bearings, and centralized auto-lube systems on excavators, loaders, and cranes. Primary challenges: water contamination, dirt ingress, high static loads on pin-and-bushing joints, and wide temperature swings.

  • Pin joints and open surfaces: adhesive Li-X or Ca-Sulfonate NLGI 1–2 EP with tackifier
  • Central auto-lube: NLGI 00–1 pumpable at −20°C minimum ambient
  • Track chain: moly-fortified NLGI 1–2 for boundary lubrication under high shock load

7. Grease vs. Lubricating Oil — The Decision Framework

FactorGreaseOil
Stays in placeYes — no reservoir neededRequires sealed or circulating system
Contamination barrierSelf-sealing functionNeeds external seals
Heat removalLimited cooling capacityExcellent via circulation
High-speed suitabilityGood up to ~DN 300,000Better above DN 300,000+
Re-application frequencyLow — long intervalsHigh — continuous or regular
System costLower (simpler housings)Higher (seals, pumps, reservoirs)
Vertical shaftsPreferred — won’t drainRequires reservoir
Best forMobile equipment, sealed bearings, hard-to-reach pointsHigh-speed machinery, turbines, gearboxes needing cooling

Decision rule: If the bearing is sealed, hard to reach, subject to contamination, runs intermittently, or sits on a vertical shaft — specify grease. If the bearing needs continuous cooling, runs above DN 300,000, or is part of an existing circulating oil system — specify oil. When both options seem viable for a critical application, run a 3–6 month comparative pilot and measure bearing temperature, vibration signature, and wear.


8. The #1 Hidden Danger: Over-Greasing and Under-Greasing

Industry surveys consistently show that over-greasing causes as many bearing failures as under-greasing — yet it remains the most overlooked lubrication hazard in plant maintenance programs. This is the topic that Mobil, SKF, and other leading guides systematically underexplain.

8.1 The Physics of Over-Greasing Failure

When excess grease is injected into a bearing housing, internal pressure rises. At operating speed, rolling elements must push grease out of their path — causing churning. Churning generates heat. Heat causes the thickener to release base oil faster than it can be re-absorbed. The remaining structure is a stiff, oil-depleted soap cake with minimal lubricating capacity. The final result: bearing failure despite the bearing appearing “full of grease.”

8.2 Under-Greasing — The Silent Killer

Under-greasing is less visible but equally destructive. By the time a bearing is audibly noisy or obviously failing, metal-to-metal contact has already caused permanent raceway damage. Adding grease at this stage quiets the bearing temporarily but does not reverse existing damage — failure is simply postponed.

Best practice: Implement ultrasound-based greasing. Ultrasonic instruments detect the friction signature of lubrication starvation in the 20,000 Hz+ frequency range — long before audible noise or temperature rise. Grease until the ultrasound signal returns to baseline, then stop. This approach simultaneously eliminates both over-greasing and under-greasing.

https://www.machinerylubrication.com/Read/31855/ultrasound-grease-lubrication】

8.3 Correct Fill Volume Formula

For electric motor bearings (SKF relubrication methodology):

Grease quantity (grams) = 0.005 × D × B

Where:

  • D = bearing outside diameter (mm)
  • B = bearing width (mm)

Example: 6310 bearing (D = 110mm, B = 27mm): 0.005 × 110 × 27 = 14.85 grams per relubrication event


9. Grease Compatibility Matrix & Changeover Protocol

Grease incompatibility is cited by SKF and NLGI as one of the most consequential — and most preventable — causes of bearing failure during maintenance events.

Bearing-grease-relubrication-interval-vs-operating-temperature-chart-showing-interval-halving-every-10°C-above-70°C

Grease Thickener Compatibility Matrix

✓ = Compatible | ✗ = Typically Incompatible | ~ = Borderline — test required | — = Same type

LiLi-XCaCa-SPUBentoneAl-CPTFE
Li
Li-X
Ca~
Ca-S~
PU
Bentone
Al-C
PTFE

Note: Some polyurea thickeners may show compatibility with lithium complex depending on specific formulation — always request compatibility test data from your supplier for critical applications.

9.1 Step-by-Step Grease Changeover Protocol

  1. Document the current grease type, thickener chemistry, and fill volume for the bearing being changed.
  2. Check the compatibility matrix. If new and old greases are incompatible, plan a full purge.
  3. Run the bearing at normal operating speed while applying new grease slowly until fresh product appears at the relief valve — purging ≥90% of the old charge.
  4. If purge is insufficient or greases are definitively incompatible: disassemble, clean bearing with solvent, re-pack from scratch with new grease at correct fill volume.
  5. Tag the bearing housing with new grease type, date, and fill volume. Update your lubrication management system (LMS).
  6. Use color-coded Zerk fittings or caps (e.g., red = polyurea, blue = Li-X, yellow = Ca-Sulfonate) to prevent future cross-contamination.

10. Industrial Grease Failure Modes — Diagnosis & Remediation

Most grease-related bearing failures are predictable and preventable. The following covers the six most common failure modes encountered in industrial plant maintenance.

Failure ModeConsequencePreventionPro Tip
Wrong grease typeBearings seize or wear rapidlyMatch thickener + base oil viscosity to OEM specPolyurea for motors, Li-X EP for mining
Over-greasingSeal blow-out, heat rise, churningAdd grease in small increments; monitor temperatureStop when fresh grease purges at relief valve
Under-greasingSurface fatigue, metal-to-metal contactSet calendar + condition-based relubrication scheduleUse ultrasound to detect lubrication starvation early
Incompatible grease mixSoftening/hardening, loss of EP film, failure within hoursFull purge before switching thickener typesUse color-coded fittings per grease type
Contaminated greaseAbrasive wear, accelerated oxidationClean Zerk fittings before every greasing eventCap drums; use dedicated grease guns per type
Incorrect storageOxidation, phase separation, shelf-life failureFIFO rotation; horizontal drum storage; 5–40°CTag drums with receipt date

11. Grease Analysis in the Field — Condition Monitoring

Grease analysis is the field equivalent of used oil analysis — yet it remains underutilized in most industrial plants. Approximately 90% of all bearings are grease-lubricated, but fewer than 10% of plants perform routine grease condition monitoring. This section covers what most grease supplier guides omit entirely.

11.1 Visual Inspection — The First Line of Defense

Observable SignLikely CauseImmediate ActionNotes
Color darkeningOxidation, contamination, overheatingGrease analysis; check temperature sensorsNormal: slight darkening. Alarm: black or burnt smell
Oil separation (bleeding)Aged thickener, thermal degradation, incorrect storageStir if minor; discard if severeMinor bleed in fresh drums is normal
HardeningOil loss via evaporation or oxidationIncrease relubrication frequencyCommon in high-temp applications
SofteningMechanical degradation, incompatible grease mixIdentify and purge contaminating greaseCan lead to leakage and starvation
Milky / white colorWater contaminationFind and eliminate water source; upgrade to Ca-SulfonateCalcium sulfonate resists this best
Metallic particlesActive bearing wear in progressImmediate inspection; send sample to labFerrography identifies wear mode

11.2 Laboratory Grease Analysis — When to Specify It

For critical bearings with replacement cost >$10,000, high failure consequence, or where relubrication intervals are being extended, laboratory grease analysis provides quantitative condition data:

  • FTIR spectroscopy — identifies thickener type, oxidation state, and contaminants
  • Penetration test (ASTM D217) — measures consistency change vs. new grease baseline
  • ICP spectrometry — detects wear metals (iron, chromium, copper) indicating active bearing damage
  • RULER test — measures remaining antioxidant life, predicts remaining service interval
  • Analytical ferrography — characterizes wear particle size, morphology, and failure mode

https://www.machinerylubrication.com/Read/30869/grease-sampling-analysis】


12. Grease Storage, Handling & Relubrication Best Practices

12.1 Storage Requirements

  • Store drums horizontally to prevent moisture ingress through drum vents — vertical storage draws in condensation as drums cool overnight
  • Maintain storage temperature 5–40°C; avoid temperature cycling (thermal pumping accelerates oil separation)
  • FIFO rotation: always use oldest stock first; typical shelf life is 2–5 years from manufacture date
  • Keep containers sealed until point of use; never return partially used grease to the original container
  • Separate grease types with clear labeling and physical separation to prevent accidental cross-contamination

12.2 Application Best Practices

  • Use dedicated, color-coded grease guns per grease type — cross-contamination most commonly occurs via shared equipment
  • Clean Zerk fittings before every greasing event — the first pump stroke drives surface contamination directly into the bearing
  • Apply grease slowly and evenly — high-pressure fast injection can force grease past rolling elements rather than through them
  • For sealed-for-life bearings (2RS): DO NOT add grease — the factory fill is sufficient for design life; additional greasing destroys seals

12.3 Relubrication Interval Formula

For bearing relubrication intervals, use the SKF relubrication methodology:

t (hours) = K × [14,000,000 / (n × √d) − 4d]

Where:

  • K = 1.0 (lithium soap) or 1.5 (polyurea)
  • n = shaft RPM
  • d = bearing bore diameter (mm)

Example: 3,000 RPM motor, 50mm bore, polyurea grease: t = 1.5 × [14,000,000 / (3,000 × √50) − 4×50] t = 1.5 × [14,000,000 / 21,213 − 200] t = 1.5 × [460] ≈ 690 hours

Reduce interval by 50% if operating temperature exceeds 70°C. Reduce by an additional 50% above 100°C. Reduce by 30–50% for contaminated (dusty/wet) environments.


13. Frequently Asked Questions

Q1: What is the difference between lithium grease and lithium complex grease?

Lithium complex (Li-X) uses a complexing agent during saponification, raising the dropping point from ~185°C (simple lithium) to >260°C and improving EP performance and oxidation stability. The cost premium is 15–30%. For industrial applications above 120°C or under high load, lithium complex is the minimum recommended specification. Simple lithium is suitable for light-duty, moderate-temperature applications where budget is the primary constraint.

Q2: Can I mix different brands of the same grease type?

Thickener type compatibility is the primary concern — two lithium complex greases from different manufacturers are generally compatible with each other. However, additive package interactions can cause issues even between same-thickener greases from different brands. When switching brands, treat it as a grease changeover event: purge before introducing the new product.

Q3: How do I know if my grease is failing in service?

Key indicators: unusual bearing noise or vibration; bearing temperature more than 15°C above established baseline; discolored grease (darkening indicates oxidation; milky appearance indicates water contamination; metallic particles indicate active wear); or grease hardening or softening versus original consistency. Laboratory grease analysis (FTIR, ICP spectrometry, penetration test) provides quantitative confirmation and remaining life estimation.

Q4: What does NLGI 2 mean — is it always the right choice?

NLGI 2 accounts for approximately 70% of global grease consumption because it balances pumpability and retention across a wide range of standard applications. However: high-speed bearings (DN >200,000) often perform better with NLGI 3; centralized auto-lube systems typically require NLGI 0–1; shock-loaded open gears may need NLGI 4–6 block grease. NLGI 2 is the correct default — but always verify against specific speed, load, and delivery method.

Q5: What causes electric motor bearings to fail shortly after regreasing?

The four most common causes: (1) Over-greasing — too much grease raises operating temperature immediately; (2) Grease incompatibility — new grease is incompatible with residual old grease, causing softening or hardening; (3) Wrong grease type — using an EP-additive grease in a lightly loaded ball bearing; (4) Contamination during greasing — not cleaning the Zerk fitting first. Over-greasing accounts for an estimated 40–60% of regreasing-induced motor bearing failures.

Q6: What are the advantages of sourcing industrial grease from Chinese manufacturers?

Modern Chinese lubricant manufacturers operating under ISO 9001:2015 with verifiable third-party ASTM test documentation provide equivalent technical performance to Western brands for the majority of industrial applications at 20–45% lower cost. The key due-diligence checklist: ISO 9001:2015 certification, verifiable ASTM test reports (D217, D2596, D2509, D1264, D3336), SDS/TDS for every grade, and API Group certification for base oil quality. Always request a paid sample and test it in your application before committing to a supply contract.

Q7: How do I recover a bearing that has been over-greased?

Stop or reduce equipment speed if possible. Open the relief fitting or drain plug and allow excess grease to purge at low speed (500–800 RPM) for 15–30 minutes. Monitor bearing temperature — it should decline within the first 30 minutes if over-greasing was the cause. If temperature remains elevated after purging, inspect for seal damage and bearing condition before returning to full load operation.

Q8: What is false brinelling and how do I prevent it?

False brinelling is raceway damage caused by oscillating micro-vibrations in stationary bearings — from nearby machinery, transport shock, or building vibration. It creates wear grooves (brinell marks) without bearing rotation, causing premature failure at startup. Prevention: rotate stored equipment by hand monthly, apply anti-fretting compound or corrosion-inhibiting grease for storage, and use vibration-isolation pads under stored motors and gearboxes.

Q9: What is the minimum order quantity for industrial grease supply?

Industrial grease is commonly available in: 400g cartridges, 1kg cans, 15kg pails, 50kg drums, and 180kg drums. For bulk B2B supply, IBC (1,000-liter intermediate bulk container) is available from select manufacturers. MOQ varies by grade and packaging format. For OEM contract supply and private label, minimum order quantities are typically negotiated per product specification.

Q10: How should used industrial grease be disposed of?

Used industrial grease is classified as hazardous waste in most jurisdictions and must not be poured down drains or mixed with general waste. Standard disposal routes: licensed waste disposal contractor, cement kiln co-processing, or approved collection services. Refer to Section 13 of the product Safety Data Sheet (SDS) for jurisdiction-specific disposal guidance — request the SDS from your grease supplier.


14. ZTSH Oil — Industrial Grease Manufacturer & Global Supplier

manufacturer for sale

ZTSH Oil (Zibo Tianshi Huasheng Petroleum Technology Co., Ltd.) manufactures industrial lubricating grease for B2B customers across 30+ countries. Our product range covers every major thickener chemistry and application sector — with full documentation, flexible packaging, and custom formulation capability.

Full Product Range

ProductThickenerNLGI GradeTemp RangeKey Application
Li-X EP GreaseLithium Complex0 / 1 / 2 / 3−30°C to 180°CGeneral industrial, mining, chassis
Polyurea Motor GreasePolyurea2 / 3−30°C to 180°CElectric motors, sealed bearings
Calcium Sulfonate ComplexCalcium Sulfonate0 / 1 / 2−20°C to 180°CMining, marine, wet environments
High-Temp Bearing GreaseBentone1 / 2Up to 250°C+Kiln, furnace, steel mill
PTFE Synthetic GreasePTFE / Synthetic1 / 2−50°C to 260°CFood-grade, extreme temp, clean-room
Open Gear GreaseLithium Complex5 / 6 Block−10°C to 160°COpen gears, racks, large pivots
NSF H1 Food-Grade GreaseAl-Complex / PTFE1 / 2−20°C to 140°CFood & beverage processing

What We Provide to B2B Buyers:

  • Full product range: Lithium Complex, Polyurea, Calcium Sulfonate, Bentone, PTFE, and specialty greases in NLGI 00–3
  • Custom formulation: base oil viscosity, NLGI grade, additive package, color, and packaging customized to OEM specifications
  • Private label / OEM supply: custom branding and documentation packages available
  • Quality documentation: ISO 9001:2015 certificate, third-party ASTM test reports, SDS, TDS, and COA for every production batch
  • Packaging: 400g cartridge through 180kg drum; IBC on request
  • Global shipping: FOB Qingdao / Shanghai; typical lead time 7–25 business days

Ready to Specify, Sample, or Source?

Contact ZTSH Oil’s technical sales team to receive: ✓ Sample kit (up to 3 grades, free for qualified B2B inquiries) ✓ Full TDS & ASTM test certificate package ✓ Competitive B2B pricing and MOQ schedule ✓ Custom formulation consultation ✓ OEM / private label program details

🌐 www.ztshoil.com | Response within 24 hours on business days

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