Modernization of Bearing Installations: When Sealed Bearings Are the Better Choice

1. Introduction: The Need for Lower Modernization

The industrial sector in the Benelux faces continuous challenges in terms of operational efficiency, sustainability and regulatory compliance. Within this context, industrial bearings play a critical role in the reliability and performance of rotating machines. Conventional, open bearing types that rely on periodic hand lubrication are often a source of inefficiency, high maintenance costs and unnecessary downtime.

Outdated bearing technologies, such as those commonly found in systems such as the VICKERS 922851 hydraulic pump/motor, can lead to significant energy losses due to increased friction, frequent lubricant changes and an increased risk of contamination. These factors directly contribute to higher Total Cost of Ownership (TCO) and lower production output. Modernizing to sealed, 'sealed-for-life' bearings offers a direct answer to these challenges. The transition to such bearings is often not only a cost-saving measure, but also a strategic step towards compliance with energy efficiency standards such as the EU Ecodesign Directive 2009/125/EC, which covers requirements for energy-related products.

This guide examines the considerations, methodologies and financial justification for replacing obsolete bearings with advanced, permanently lubricated alternatives. The goal is to increase operational reliability and improve the overall sustainability of industrial processes.

2. Analysis of Existing Bearing Installations

Before proceeding with modernization, a thorough analysis of the existing bearing installations is essential. This evaluation focuses on identifying weaknesses and quantifying the potential benefits of an upgrade. A structured approach includes the following criteria:

“Maintenance evaluation in accordance with NEN-EN 13306:2017 defines the terminology and methodology for analyzing maintenance needs.”

The findings from this analysis serve as a basis for the selection of suitable modern alternatives and the calculation of the Return on Investment (ROI).

3. Modern Bearing Solutions

Modern sealed bearings, also called 'sealed-for-life' bearings, are distinguished by their internal lubrication and robust seals. They require no hand lubrication during their operational life and provide superior protection against external contaminants. An example of such a solution is an advanced sealed deep groove ball bearing (e.g. type 2RS or 2RSR) filled with a high-quality, long-life lubricant.

4. ROI Calculation: The Economic Justification

The switch to sealed bearings is not only a technical improvement, but also a sound financial investment. To illustrate the ROI, consider a scenario for an industrial pump unit system with two bearings, operational 24/7 (8,760 hours/year) in an average production facility in the Benelux.

Current Situation (Obsolete Open Bearings):

• Purchase costs of bearings: 2 x €50 = €100 per year (lifespan of 1 year).
• Lubricants: €100 per year (grease, purchase and handling).
• Labor for hand lubrication: 2 hours/month x 12 months x €60/hour = €1,440 per year.
• Labor for bearing replacement: 4 hours/year x €60/hour = €240 per year.
• Downtime costs due to replacement/lubrication: 8 hours/year x €500/hour (estimated production loss) = €4,000 per year.
• Energy loss due to friction: Estimated at 0.5 kW extra continuous power consumption. At €0.20/kWh: 0.5 kW x 8760 hours/year x €0.20/kWh = €876 per year.
• Total annual costs (Current): €100 + €100 + €1,440 + €240 + €4,000 + €876 = €6,756.

New Situation (Modern Sealed Bearings):

• Purchase costs for bearings: 2 x €300 = €600 per 5 years, so €120 per year.
• Lubricants: €0 per year (permanently lubricated).
• Labor for hand lubrication: €0 per year.
• Labor for bearing replacement: 4 hours/5 years x €60/hour = €48 per year.
• Downtime costs due to replacement: 8 hours/5 years x €500/hour = €800 per year.
• Energy loss due to friction: Estimated at 0.1 kW continuous power consumption. At €0.20/kWh: 0.1 kW x 8760 hours/year x €0.20/kWh = €175.20 per year.
• Total annual costs (New): €120 + €0 + €0 + €48 + €800 + €175.20 = €1,143.20.

Financial Results:

• Annual savings: €6,756 - €1,143.20 = €5,612.80.
• Initial investment (bearings): €600.
• Payback Period: €600 / €5,612.80 ≈ 0.106 years (approximately 1.27 months).

This calculation shows that, despite higher initial purchase costs, the rapid payback period underlines the financial benefits of modernization. The annual savings of €5,612.80 are significant and directly contribute to operational profitability.

5. Implementation plan

Successful implementation of bearing modernization requires a phased approach to minimize production disruptions and ensure a smooth transition.

Phase 1: Analysis and Planning (Week 1-2)

• Detailed condition analysis of the existing machines (e.g. vibration analysis in accordance with ISO 10816, thermography).
• Identification of critical machines and bearing applications with high maintenance frequency or energy losses.
• Selection of suitable modern sealed bearings, including compatibility check (dimensions, load, speed). UNITEC-D can advise here and supply the necessary components.
• Drawing up a detailed project plan and budget.
• Requesting necessary certificates (e.g. CE marking for new components).

Phase 2: Purchasing and Preparation (Week 3-4)

• Order the selected bearings and required installation tools via the UNITEC-D E-Catalog.
• Planning the installation in consultation with production planning to minimize downtime.
• Training maintenance personnel in the installation and condition monitoring of the new bearings.
• Compliance with NEN 3140 for electrical safety when working on machines.

Phase 3: Installation (Week 5-6, per machine)

• Controlled standstill of the machine in question.
• Dismantle the old bearings with suitable tools to prevent damage to shafts or bearing seats.
• Thorough cleaning and inspection of the bearing seats and shafts for tolerances and damage (according to ISO 1132-1 for bearing tolerances).
• Installation of the new sealed bearings using heating techniques (induction) or hydraulic aids to avoid mechanical damage.
• Checking the correct fit and alignment (according to ISO 1940-1 for balancing).

Phase 4: Commissioning and Monitoring (Week 7-8)

• Gentle start-up of the machine and initial monitoring of temperature, vibration and noise.
• Detailed condition monitoring after installation to validate performance and establish reference values.
• Documentation of the work performed and the new operating parameters.
• Periodic evaluation of energy savings and reduction in maintenance costs.

6. Technical Challenges and Solutions

The modernization of bearings can present technical challenges. Anticipating these problems is crucial for successful implementation.

• Sizing and Compatibility: Older machines may have different bearing dimensions that are not available as standard in modern sealed versions. Solution: Consult UNITEC-D for advice on special bearings or adapter sleeves. Sometimes a slight modification of the bearing seat is required. Tolerances in accordance with NEN-ISO 286 for fits are leading.
• Environmental conditions: Extreme temperatures (>150 °C), aggressive chemicals or vacuum conditions require special sealing materials and lubricants. Solution: Select bearings with specific seals (e.g. Viton for higher temperatures) and chemically resistant lubricants.
• Vibration behavior: New bearings may exhibit a different vibration spectrum than old ones. Solution: Perform a baseline measurement after installation and use ISO 15242-1 for the correct interpretation of bearing vibration measurements.
• Installation Quality: Improper installation is a primary cause of premature bearing failure. Solution: Use specialized tools for assembly and disassembly. Provide trained staff who work according to best practices.
• Resistance to Change: Maintenance personnel may be reluctant to abandon familiar lubrication routines. Solution: Clear communication about benefits, training and involvement in the project, with an emphasis on reduced workload and increased reliability.

7. Practical example: Modernization of a pump unit system

A food processing company in Belgium suffered from frequent bearing failures in a critical pump unit system, an analogue of the VICKERS 922851, which supplied raw materials. The old open roller bearings required hand lubrication every 2 weeks and failed on average every 9 months. Each failure resulted in 8 hours of production downtime and significant repair costs.

Situation 'Before' Modernization:

• Equipment: Industrial pump for viscous liquids.
• Bearing type: Two open roller bearings (lifespan approx. 6,500 operating hours).
• Maintenance: Frequent hand lubrication, 2 hours/month per pump.
• MTBF: Average 6,500 hours (approx. 9 months).
• Downtime: 8 hours per outage.
• Energy consumption: Pump consumes 5 kW, of which an additional 0.5 kW is attributed to bearing friction.
• Annual costs: Approximately €6,756 (see ROI calculation).

Situation 'After' Modernization:

The company decided to replace the open bearings with high quality, advanced sealed deep groove ball bearings (2RS type), selected in collaboration with UNITEC-D. The bearings were filled with a lifetime, NSF H1 certified grease. The installation was carried out according to a tight schedule during a planned production stop, in accordance with ATEX guidelines for the zone 22 classified environment.

• Bearing type: Two sealed deep groove ball bearings (2RS type, service life approx. 40,000 operating hours).
• Maintenance: No more hand lubrication required. Focus on condition monitoring.
• MTBF: Increased to 40,000 hours (approx. 54 months or 4.5 years).
• Downtime: Dramatically reduced; planned replacement every 4.5 years.
• Energy consumption: Pump consumes 4.6 kW, friction loss reduced by 0.4 kW.
• Annual costs: Reduced to approximately €1,143.20 (see ROI calculation).

Measurable KPIs:

• Downtime reduction: From 8 hours every 9 months to 8 hours every 4.5 years.
• MTBF increase: From 6,500 hours to 40,000 hours (+515%).
• Energy savings: 0.4 kW x 8760 hours/year = 3,504 kWh/year.
• Maintenance cost reduction: Approximately 83% annual savings on direct maintenance.
• Compliance: Better compliance with ISO 50001 (Energy Management Systems).

8. Commissioning and Validation

After installation of the new bearings, a careful commissioning and validation procedure is crucial to confirm correct operation and improvements achieved. This process includes:

• Test procedures:
  • Vibration analysis: Performed according to ISO 10816 to assess the mechanical vibration status of the machine. The vibration levels of the new bearings should be significantly lower than before and within the bearing manufacturer's specifications.
  • Thermal inspection: The operating temperature of the bearings is checked using thermography. Stable and lower operating temperatures (<70°C, or as specified by manufacturer) indicate optimal lubrication and minimal friction.
  • Acoustic measurement: Sound levels are measured to detect irregularities that may indicate installation errors or damage.
  • Test run: The machine is tested under full load for a certain period of time to confirm its long-term stability and reliability.
• Acceptance criteria:
  • The measured vibration values ​​are within the limits of the bearing manufacturer and the machine supplier.
  • The operating temperature of the bearings remains stable and within the optimal range.
  • No abnormal sounds are noticeable.
  • The machine functions without malfunctions during the trial period.
  • All relevant documentation, including maintenance schedules and machine manuals, has been updated.
• Conformance and Certification: Newly installed bearings and their mounting must comply with relevant product standards and safety guidelines. This may include the presence of a CE mark for the components, and for specific environments, such as explosion hazards, compliance with ATEX guidelines.

9. Conclusion

The modernization of bearing installations through the implementation of sealed-for-life bearings represents a strategic investment with demonstrable benefits. The significant reduction in maintenance costs, the reduction in energy consumption and the drastic reduction in unplanned downtime directly contribute to higher operational efficiency and improved compliance with environmental standards. The initial higher costs are quickly compensated by the long-term savings and increased reliability of the production processes.

For plant engineers, maintenance managers and Capex decision makers in the Benelux industry, the 'still works' argument is insufficient when considering the Total Cost of Ownership of legacy systems. The switch to modern, sealed bearings is a proactive step towards a more sustainable and economically beneficial business operation.

Discover the possibilities for your specific application and find the right high-quality bearing solutions for your modernization projects via the UNITEC-D E-Catalog.

10. References

• EU Ecodesign Directive 2009/125/EC – Framework for setting ecodesign requirements for energy-related products.
• ISO 10816 – Mechanical vibrations – Evaluation of machine vibrations by measurements on non-rotating parts.
• ISO 1132-1:2017 – Roller and rolling element bearings – Tolerances – Part 1: Tolerance values.
• ISO 15242-1:2015 – Rolling and rolling element bearings – Measurement of vibration – Part 1: Fundamentals and measurement methods.
• ISO 1940-1:2003 – Mechanical vibration – Requirements for balancing rigid rotors – Part 1: Determination of permissible unbalance.
• ISO 50001:2018 – Energy management systems – Requirements with guidelines for use.
• NEN 3140 – Operation of electrical installations – Low voltage.
• NEN-EN 13306:2017 – Maintenance – Terminology for maintenance.
• NEN-ISO 286-1:2010 – ISO tolerance system – Part 1: Basics of tolerances, deviations and fits.
• Directive 2014/34/EU (ATEX Directive) – Harmonization of the laws of the Member States relating to equipment and protective systems intended for use in potentially explosive atmospheres.