What is Klüber Klüberplex BEM 41-132 Multi-Purpose?
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What is Klüber Klüberplex BEM 41-132 Multi-Purpose?
Klüberplex BEM 41-132 is a high-temperature, long-term lubricating grease formulated by Klüber Lubrication for rolling and plain bearings operating under demanding conditions. Classified under DIN 51502 as KPHC 2 N-30 L, the product belongs to the Klüberplex BEM family of greases engineered around a lithium complex soap thickener dispersed in a blend of synthetic hydrocarbon and mineral base oils. The "BEM" designation refers to its intended use in Betriebs- und Einbaufertigung (operational and assembly lubrication), reflecting its dual role in initial factory fill and ongoing service relubrication. With an NLGI consistency grade of 2 and a service temperature range spanning from -40 °C to +150 °C, this grease is commonly specified for general machinery applications where a single lubricant must perform across a broad spectrum of speeds, loads, and environmental conditions. Its balanced formulation incorporates anti-wear, anti-oxidation, and anti-corrosion additive packages, making it a practical selection for maintenance engineers seeking to consolidate lubricant inventories. The product is available in pack sizes ranging from 400 g cartridges to 170 kg drums to accommodate both manual and centralised lubrication systems.
Key Technical Characteristics
The base oil system in Klüberplex BEM 41-132 combines synthetic hydrocarbon oil with mineral oil, yielding a kinematic viscosity of approximately 120 mm²/s at 40 °C and roughly 14 mm²/s at 100 °C. This viscosity profile provides a lubricating film of sufficient thickness for bearing surfaces at typical operating temperatures while maintaining adequate fluidity for low-temperature pumpability down to -40 °C. The synthetic hydrocarbon component contributes to the grease's oxidation stability -- a critical attribute for extended service intervals where the lubricant must resist thermal degradation over months or years of continuous operation.
The thickener is a special lithium complex soap, which distinguishes this product from conventional lithium greases that rely on simple lithium 12-hydroxystearate. Lithium complex thickeners offer a higher dropping point (≥ 250 °C for this formulation, as measured per DIN ISO 2176) compared to the approximately 190–200 °C typical of simple lithium greases. This elevated thermal threshold means the grease retains structural integrity at temperatures where simpler formulations would liquefy and migrate away from the bearing contacts. The complex soap structure also contributes to improved shear stability and more controlled oil release -- properties that directly influence bearing service life.
The NLGI grade 2 consistency (worked penetration range of 265–295 × 0.1 mm at 25 °C, per DIN ISO 2137) places this grease in the most commonly applied category for industrial rolling bearings. An NLGI 2 grease is firm enough to remain in place within horizontal and moderately inclined bearing housings, yet soft enough to be distributed effectively by the rolling elements and to be pumped through centralised lubrication lines. The density at 20 °C is approximately 0.90 g/cm³. In the FAG FE9 rolling bearing test (DIN 51821, part 2) conducted at 150 °C with a 1,500 N load and 6,000 min⁻¹ speed, the grease achieves an L50 service life exceeding 100 hours, confirming its suitability for high-temperature bearing applications. The speed factor (n × dₘ) is rated at approximately 1,000,000 mm/min. The copper corrosion rating of 1-120 (DIN 51811, 24 h at 120 °C) and an EMCOR corrosion protection result of ≤ 1 (DIN 51802, distilled water) demonstrate effective corrosion inhibition.
How Klüberplex BEM Lubricants Work
The function of Klüberplex BEM 41-132 in a rolling bearing follows the established principles of grease lubrication. The grease is a semi-solid dispersion in which the lithium complex soap thickener forms a three-dimensional fibre network that immobilises the base oil through capillary forces and surface tension. When the bearing begins to rotate, shear forces applied by the rolling elements cause a portion of the base oil to separate from the thickener matrix -- a process known as bleed or oil release -- and migrate into the rolling contact zone. There, the oil forms an elastohydrodynamic (EHL) lubricating film that physically separates the rolling elements from the raceway surfaces, preventing metal-to-metal contact and the associated adhesive wear.
At start-up and at very low speeds, or under high loading conditions, the EHL film may be insufficient to fully separate the contacting surfaces. Under these boundary lubrication conditions, the anti-wear additives incorporated into Klüberplex BEM 41-132 become active. These additives form protective tribochemical layers on the bearing steel surfaces, reducing friction coefficients and mitigating surface damage even when the full oil film collapses. This dual-mode protection -- hydrodynamic at speed and boundary during start-stop or overload events -- is fundamental to the grease's long-term performance.
The controlled oil release rate (≤ 4 % by weight after 7 days at 40 °C per DIN 51817; ≤ 8 % after 30 hours at 150 °C per FTMS 791 C 321) is engineered to provide consistent lubrication over extended operating periods. Excessive bleed would deplete the grease reservoir prematurely; insufficient bleed would starve the bearing contacts. The lithium complex thickener structure achieves this balance by maintaining a stable but permeable fibre matrix. At elevated temperatures, the oxidation inhibitors within the formulation consume oxygen and neutralise catalytic metal ions that would otherwise accelerate oil degradation, reflected in the oxidation stability test result (DIN 51808, 100 hours at 99 °C) of ≤ 0.2 bar pressure drop. The shear viscosity at 25 °C and 300 s⁻¹ falls within 3,000–6,000 mPas, providing a practical measure of the grease's flow behaviour under dynamic conditions relevant to bearing churning and distribution.
Industrial Applications
Klüberplex BEM 41-132 is specified across a diverse range of industrial sectors where rolling and plain bearings require a reliable, cost-effective lubricant with broad operating parameters. The following applications represent commonly documented use cases:
1. Electric Motors (IEC and NEMA Frame Sizes): Deep groove ball bearings in horizontal and vertical electric motors benefit from the grease's NLGI 2 consistency, which stays in the bearing housing without excessive churning losses. The oxidation stability supports extended relubrication intervals aligned with typical motor maintenance schedules. The low running torque at low temperatures (≤ 200 mNm at -40 °C per IP 186) ensures reliable cold-start performance.
2. Industrial Pumps: Centrifugal and positive-displacement pump bearing assemblies operate under steady loads and speeds within the grease's rated range. The EMCOR corrosion rating of ≤ 1 ensures that moisture ingress from pump seal leakage does not immediately compromise bearing surface protection.
3. Fans and Blowers (Including Hot Air Applications): Bearing housings on axial and centrifugal fans in drying ovens and HVAC systems encounter elevated ambient temperatures. The 150 °C upper service temperature and the ≤ 8 % oil separation at this temperature make the grease suitable for these environments, where conventional lithium greases would degrade more rapidly.
4. Paper-Making Machines (Dry Section): Cylindrical and spherical roller bearings in the drying section of paper machines operate at sustained elevated temperatures with moderate to high loads. The FAG FE9 test result confirms adequate service life under these conditions, and the controlled oil bleed rate provides consistent lubrication over production cycles that may span weeks without interruption.
5. Textile Machinery (Dry Processing): Bearings in spinning frames, drawing machines, and drying cylinders are exposed to fibres, dust, and elevated temperatures. The grease's mechanical stability under shear (roll stability per ASTM D 1831, penetration difference ≤ +80 × 0.1 mm after 50 h at 100 °C) means the consistency remains within specification even under continuous mechanical working.
6. Wind Turbine Generator Bearings: Generator-side deep groove and cylindrical roller bearings in wind turbines demand greases with extended service life to reduce tower climbs for maintenance. The oxidation resistance and controlled oil release support the long relubrication intervals required in this application.
7. Conveyor Systems: Idler and pulley bearings in belt conveyors for mining, aggregate handling, and bulk materials processing operate in dusty, often wet conditions. The corrosion protection rating and water resistance make the product a practical choice where wash-down or rainfall exposure is a concern.
8. Agricultural Machinery: Bearings in balers, harvesters, tillage equipment, and irrigation pivot points encounter substantial contamination from soil, crop residue, and moisture. While sealed or shielded bearings are preferred in these environments, Klüberplex BEM 41-132 provides a baseline of corrosion and wear protection when regreasing is part of the maintenance schedule.
9. Automotive Component Bearings: Clutch release bearings, alternator bearings, water pump bearings, and viscous fan clutch bearings in passenger and commercial vehicles are factory-filled applications where the grease's temperature range, shear stability, and low-temperature torque characteristics meet automotive subsystem requirements.
10. Air Separators and Mineral Processing Equipment: In the base materials and cement industries, air separator bearings operate under moderate heat and continuous rotation. The grease's capacity to perform without frequent reapplication suits production environments where unscheduled downtime carries significant cost.
11. General Factory Automation and Material Handling: Bearings in automated guided vehicles (AGVs), palletisers, packaging machinery, and overhead cranes benefit from a single grease specification that covers the speed, load, and environmental conditions typical of factory floors. This simplifies lubricant inventory management across large manufacturing facilities.
How It Compares
Within the Kluberplex BEM family, the 41-132 variant occupies a position optimised for general-purpose applications where a balance of performance and economy is required. Compared with conventional lithium greases conforming to ISO 6743-9 L-XBCEA 2 (simple lithium soap, mineral oil, NLGI 2), Klüberplex BEM 41-132 provides a meaningfully higher dropping point (≥ 250 °C versus approximately 190 °C), improved oxidation resistance as measured by the DIN 51808 pressure drop test, and a wider service temperature range extending to -40 °C at the lower end. These differences translate directly into longer bearing service life in elevated-temperature applications and greater flexibility in cold-start environments.
For applications requiring even higher thermal stability, Klüber offers greases in the Klüberplex BEM 41-141 and 41-142 range, which utilise fully synthetic base oils and may achieve upper service temperatures beyond 160 °C. These products are typically selected for extreme-duty applications such as kiln truck bearings, furnace fans, and certain chemical processing equipment where temperatures consistently exceed the 150 °C ceiling of the 41-132. Conversely, for low-speed, high-load applications where EP (extreme pressure) performance is the primary concern, greases containing solid lubricants (graphite, MoS₂, PTFE) or formulated with higher base oil viscosity may be more appropriate. The 41-132 does not carry a formal EP classification and should not be the first choice for heavily loaded plain bearings operating under pure boundary lubrication with high sliding friction. In situations where water wash-out resistance is critical -- such as in submerged bearings, wet-end paper machine sections, or marine deck equipment -- a calcium sulphonate complex or aluminium complex grease may offer advantages in water resistance, though the 41-132's EMCOR rating of ≤ 1 confirms it remains a capable performer in mildly wet conditions. For food-processing environments requiring NSF H1 registration, alternative Klüber products from the Klüberfood NH1 series should be specified, as Klüberplex BEM 41-132 is not certified for incidental food contact.
Application & Maintenance Guidelines
Klüberplex BEM 41-132 should be stored in its original, unopened container in a dry, frost-free environment. Under these conditions, the manufacturer specifies a minimum shelf life of approximately 36 months from the date of manufacture. Containers that have been opened should be used promptly, and care should be taken to prevent contamination of the grease surface by dust, dirt, or moisture, as foreign particles can act as stress concentrators within a rolling bearing and initiate premature fatigue spalling.
Application can be performed manually using a spatula or brush for open bearing housings, or via a grease gun for bearings equipped with lubrication nipples. For centralised automatic lubrication systems -- including Klübermatic single-line and progressive systems -- the grease has demonstrated pumpability suitable for these setups, though the low-temperature flow pressure of < 1,600 mbar at -30 °C (DIN 51805) should be verified against the specific system's pressure capabilities and line lengths. When switching to Klüberplex BEM 41-132 from another grease, compatibility should be assessed: greases based on lithium or lithium complex soaps are generally miscible with each other, but mixing with sodium, bentonite, or polyurea-thickened products may result in consistency changes (softening or hardening) that could affect bearing performance. A best practice is to purge the bearing housing thoroughly with the new grease to displace the old lubricant as completely as practical.
Relubrication intervals should be determined based on bearing type, size, speed, load, operating temperature, and environmental contamination risk. The FAG FE9 rolling bearing test result and the speed factor rating of 1,000,000 mm/min provide reference points, but field conditions always differ from laboratory test environments. Condition monitoring through vibration analysis, temperature trending, and periodic grease sampling (assessing consistency, oil separation, and oxidation by infrared spectroscopy, where available) allows maintenance planners to optimise relubrication intervals for actual operating conditions rather than relying solely on generic guidelines. Over-greasing should be avoided, particularly in high-speed bearings, as excessive grease volume increases churning losses, raises operating temperatures, and can accelerate grease degradation.
Frequently Asked Questions
Q1: What is the difference between a lithium complex grease and a simple lithium grease, and why does it matter for Klüberplex BEM 41-132?
A lithium complex grease utilises a thickener formed by the reaction of lithium hydroxide with both a long-chain fatty acid (typically 12-hydroxystearic acid) and a short-chain complexing agent (such as a dicarboxylic acid or boric acid). This dual-reaction chemistry produces a thickener structure with a significantly higher dropping point than simple lithium soap greases -- ≥ 250 °C versus approximately 190 °C. In practical terms, the complex thickener in Klüberplex BEM 41-132 allows the grease to remain in place at sustained operating temperatures up to 150 °C without liquefying and leaking from the bearing housing. The complex structure also provides improved mechanical shear stability and more uniform oil release over the grease's service life, which contributes to more predictable relubrication intervals.
Q2: Can Klüberplex BEM 41-132 be used in electric motor bearings, and what relubrication frequency is recommended?
Yes, Klüberplex BEM 41-132 is commonly specified for deep groove ball bearings in electric motors across a range of frame sizes. The NLGI 2 consistency is appropriate for standard motor bearing configurations, and the low running torque at cold temperatures supports reliable motor start-up. Relubrication frequency depends on bearing size, motor speed, operating temperature, and environmental conditions. As a general starting point, bearings operating at 70 °C to 110 °C -- the optimal window for lifetime lubrication with this product -- may achieve extended intervals, but motors running continuously near the 150 °C upper limit will require more frequent regreasing. Vibration monitoring and temperature trending are recommended to establish site-specific intervals. Always refer to the motor manufacturer's lubrication specifications and the Klüber datasheet for detailed guidance.
Q3: How does Klüberplex BEM 41-132 perform in wet or humid environments?
The grease demonstrates effective water resistance, as indicated by its EMCOR corrosion test rating of ≤ 1 (DIN 51802, tested with distilled water over one week). This rating means that bearing surfaces remain protected against corrosion under static exposure to moisture. In dynamically wet conditions -- such as bearings exposed to water spray, high-pressure wash-down, or condensation -- the grease continues to provide adequate protection for typical industrial environments. However, for permanently submerged bearings or applications with continuous high-pressure water impingement, a grease specifically formulated for extreme water resistance (such as a calcium sulphonate complex type) may provide longer service intervals. Bearings operating in wet conditions should ideally be equipped with effective sealing arrangements (labyrinth or lip seals) to minimise water ingress regardless of the grease selected.
Q4: Is Klüberplex BEM 41-132 compatible with polyurea-thickened greases that are commonly factory-filled in sealed bearings?
Mixing greases with chemically dissimilar thickener types can result in consistency changes -- either excessive softening or hardening -- that may impair bearing lubrication. Lithium complex greases (such as Klüberplex BEM 41-132) and polyurea greases use fundamentally different thickener chemistries, and their compatibility cannot be assumed without testing. If a bearing is factory-filled with a polyurea grease and an operator wishes to switch to Klüberplex BEM 41-132 for service relubrication, the recommended approach is to thoroughly purge the existing grease from the bearing housing before applying the new product. In sealed or shielded bearings that cannot be purged, mixing should be avoided unless compatibility can be confirmed through laboratory testing. When in doubt, consult the bearing manufacturer or Klüber Lubrication technical support for application-specific guidance.
Q5: What base oil viscosity does Klüberplex BEM 41-132 have, and why does viscosity matter for bearing lubrication?
The base oil blend in Klüberplex BEM 41-132 has a kinematic viscosity of approximately 120 mm²/s at 40 °C and about 14 mm²/s at 100 °C. Base oil viscosity is the single most important parameter governing the thickness of the lubricating film that separates rolling elements from raceways in a bearing. If the viscosity is too low, the film collapses under load, leading to metal-to-metal contact and accelerated wear. If it is too high, fluid friction (churning losses) increases, raising operating temperature and reducing energy efficiency. The 120 mm²/s viscosity at 40 °C places this grease in a range that is widely accepted for general industrial rolling bearings with moderate speeds and loads. The corresponding viscosity index indicates adequate retention of film thickness as temperature rises. For bearings operating at very low speeds under heavy loads (where a thicker oil film is needed) or at very high speeds (where a thinner oil is preferred to reduce frictional heat), an alternative product with a different base oil viscosity may be more suitable. Refer to the bearing manufacturer's viscosity ratio (kappa) recommendations for the specific application.
Sourcing Klüberplex BEM Products
KOEED is an authorised distributor of Klüber Lubrication products, providing genuine Klüberplex BEM 41-132 and the broader Klüberplex grease portfolio to industrial customers worldwide. As an authorised channel, KOEED supplies product with verified traceability, proper storage conditions, and full manufacturer warranty support. Technical datasheets and material safety data sheets (MSDS) are available upon request to support your procurement and EHS documentation requirements. For pricing, volume quotations, and technical consultation for your specific application, contact the KOEED sales team at Moritta@KOEED.COM. International shipping is available to support maintenance operations across multiple geographic regions.