1. The “Power Generation Dilemma“ of Bearing Replacement in the Power Industry

The power industry is the energy cornerstone of the national economy. Thermal power, hydropower, nuclear power, wind power, biomass power and cogeneration plants all require long-term uninterrupted continuous operation. Once a generator set is connected to the grid, it often runs continuously for months or even the entire year without stopping. Coal handling, ash removal, desulfurization, denitrification and steam-water systems contain a large number of large transmission equipment – belt conveyors, scraper conveyors, crushers, induced/forced draft fans, feeders, cooling tower fans and other critical equipment – operating year-round under high dust, high temperature, high humidity and continuous heavy-load conditions.

 

Large power plant feedwater pumps, condensate pumps and circulating pumps are the core auxiliary equipment for thermal cycling, steam-water transport and unit cooling. Their operational stability directly determines the full-load, long-cycle, safe and economical operation of generator sets. Power plant pumps generally feature large flow rates, high heads and 24/7 continuous operation. Thermal power plant turbine-generator auxiliary systems operate under severe conditions of high temperature, micro-dust, continuous high-speed rotation and alternating vibration loads.

 

When bearings in these machines fail, maintenance teams face a far more complex “power generation dilemma“ than ordinary industrial equipment – traditional solid bearing replacement requires disassembly of shafts, couplings, gearboxes and numerous surrounding components, with confined working spaces and compact equipment layouts – the entire replacement cycle takes days or weeks, while generator set downtime losses amount to tens of millions or even hundreds of millions of yuan.

 

Typical pain points of traditional solid bearings in the power industry:

 

Equipment cannot be stopped, maintenance causes huge generation losses – Shutdown of coal handling, ash removal or desulfurization causes boiler feed interruption, furnace slag accumulation and emission exceeding standards, potentially leading to unit load reduction or shutdown. Traditional solid bearing replacement takes 1-3 days per location, with hidden costs including generation losses, start-stop energy losses and environmental penalties being extremely high.

 

Harsh operating conditions, rapid bearing wear – Thermal power plants have high dust concentrations, with coal dust and ash easily invading bearing interiors; induced draft fans and flue equipment endure long-term high-temperature radiation; cooling towers and outdoor conveyors experience moisture, condensation and corrosive humidity; continuous vibration causes micro-deflection of shafts. Conventional solid bearings typically last only 4-8 months, with high replacement frequency.

 

Compact equipment layout, narrow maintenance access – Equipment such as slag conveyors, enclosed conveyors, flue fans and coal crushers have enclosed structures with shafting buried inside frames and limited space. Conventional solid bearings cannot be axially installed or removed – requiring cutting or dismantling of frames, significantly increasing maintenance work.

 

High maintenance costs, high spare parts consumption – Traditional bearing disassembly requires cranes, specialized personnel and large quantities of consumables. Frequent replacement of bearings, seals and grease results in persistently high long-term maintenance costs. Repeated disassembly also easily damages main shafts, causing journal wear, outer ring rotation and shaft bending.

 

2. NMT Split Bearings for the Power Industry: Power Generation Without Shaft Removal, Quick Bearing Replacement

NMT split bearings for the power industry perfectly combine the core advantage of split bearings – “no-shaft-removal installation“ – with the stringent requirements of power generation equipment. The inner ring, outer ring, rolling elements and cage are all split along the axial direction – installation requires no removal of shafts, couplings, gearboxes or any other core components – assembly is completed directly on the shaft in situ.

 

More critically – NMT split bearings can be replaced without removing motors, couplings, without moving shaft systems, without using large lifting equipment. This is like installing a “service door“ on power generation equipment, enabling true “online“ maintenance. Given that power industry equipment typically operates 24/7, split bearings enable in-situ maintenance without disassembly, significantly reducing maintenance difficulty in high-altitude and equipment-dense areas, ensuring uninterrupted power equipment operation. Compared to traditional solid bearings, split bearings can reduce maintenance time by over 80%.

 

▸ Full Split + Heavy-Duty Construction: Every Piece Can “Go in Separately, Rotate Together“ – Withstanding Power Plant Conditions

 

Every component of an NMT split bearing for the power industry is split – split inner ring, split outer ring, split cage with rolling elements, split seals. During installation, these half-ring components are assembled sequentially around the shaft. After being locked with high-strength bolts, they form a precision transmission unit with performance fully equivalent to a solid bearing. Precision step-type mating or V-shaped split joint design at the split interfaces ensures load capacity and rotational precision equal to solid bearings.

 

In terms of materials, NMT offers a complete impact-resistant steel system for power industry heavy-load, continuous, high-dust applications – carburized bearing steel with deep-case hardening achieves uniform surface hardness HRC60-64 while the core maintains sufficient toughness to absorb impact loads. Split bearings use high-strength alloy materials and precision raceway processing, with strong structural rigidity that shares most axial loads from unit main shafts, effectively buffering impact vibration from equipment start-stop and load fluctuations, greatly reducing wear rates on main shafts and transmission components. For high-humidity environments such as cooling towers and outdoor conveyors, stainless steel or special anti-corrosion coatings are available.

 

▸ No-Shaft-Removal Installation: No Motor Removal, No Coupling Removal, No Large Lifting Equipment

 

The core value of NMT split bearings for the power industry is – bearing replacement without moving the shaft, without removing motors and couplings, without using large lifting equipment. This means for power plant feedwater pump bearing replacement, the motor stays in place, couplings stay in place, pump piping stays in place. For coal handling system conveyor bearing replacement, no drive pulley or gearbox disassembly is required. Maintenance personnel simply open the bearing housing, remove the old bearing halves, install the new bearing halves, and tighten the bolts – complete. In emergency failure situations, auxiliary equipment operation can be quickly restored, avoiding generation losses.

 

▸ Interchangeable with Standard Heavy-Duty Solid Bearings: Seamless Replacement, No Modifications

 

NMT split bearings for the power industry are designed with full interchangeability with standard heavy-duty solid bearings in mind. In most cases, the outer diameter and outer ring width of split bearings are identical to standard spherical roller bearings (222, 230, 231, 239, 240, 241 series). This means power plants can directly replace existing solid bearings in their equipment with NMT split bearings without any machining modifications to bearing housings.

 

▸ Split Housed Bearing Units Option – NMT also offers split housed bearing units that integrate split bearings and housings as a complete assembly. Suitable for power plant coal conveyors, bucket wheel stacker-reclaimers, scraper conveyors and other equipment, significantly reducing maintenance costs. Housings are available in steel, gray cast iron or ductile iron to suit different application requirements.

 

3. Full Series Split Bearing Types for the Power Industry

NMT offers a complete split bearing product system covering multiple power generation equipment applications:

 

▸ Power Industry Split Spherical Roller Bearings

 

Split spherical roller bearings are the most widely used split bearing type in power plants. NMT split spherical roller bearings are specifically designed for power plant feedwater pumps, circulating pumps, induced draft fans, coal mills and coal conveyors – inner rings, outer rings and cages with rollers are all split in half. Spherical outer ring raceways and barrel-shaped rollers provide self-aligning capability, effectively compensating for shaft deflection and installation errors. Excellent sealing characteristics ensure reliable operation in dusty power plant environments. Widely used in turbine auxiliaries, large pumps, fans, coal handling systems and other critical power plant equipment. The split structure allows bearing replacement without removing drive systems. Schaeffler‘s split asymmetrical spherical roller bearings can reduce bearing replacement costs by 50%, with the entire replacement process completed inside the nacelle without removing generators or powertrains.

 

▸ Power Industry Split Cylindrical Roller Bearings

 

Split cylindrical roller bearings use cylindrical rollers to carry high radial loads, with extremely strong radial load capacity, low friction coefficient, high limiting speed, low operating temperature rise and excellent coaxiality precision. Inner and outer rings each split in half, with one or two rows of cylindrical rollers in a split cage. Widely suitable for power plant large feedwater pumps, condensate pumps, circulating pumps and other medium-high speed continuous operation equipment. The split half construction enables installation and removal without disassembling shafts and pump piping, perfectly adapting to the maintenance needs of large power pumps and circulating pumps, and has become the mainstream supporting bearing for power pump stations and unit water circulation systems. Power plant bucket wheel stacker-reclaimers, ship unloader hoist drives and other equipment also widely use split cylindrical roller bearings.

 

▸ Power Industry Split Tapered Roller Bearings

 

NMT split tapered roller bearings feature two rows of opposed tapered rollers, capable of simultaneously bearing radial and bidirectional axial loads, specifically designed for combined loads. Suitable for power plant fans, pumps and other fixed-end bearing positions requiring combined loads. Available in a complete range of specifications, widely used in thermal, nuclear, hydro and other power facilities.

 

▸ Split Housed Bearing Units

 

NMT offers split housed bearing units that integrate split bearings and housings as a complete assembly. SNU/SNL series split housed bearing units are suitable for medium-speed and heavy-load applications, widely used in power plant conveyors, fans, bucket wheel stacker-reclaimers and other equipment. Housings feature split design with upper and lower halves, including split bearing housings, high-strength fastening bolts, seal caps, adjustment shims and other components. Metal adjustment shims at housing joint faces enable precise adjustment of radial clearance and coaxiality, compensating for positional deviations from equipment thermal expansion.

 

4. Specialized Sealing and Lubrication Systems – Adapting to High Dust, High Temperature and High Humidity Environments

Power equipment operates year-round under harsh conditions of high dust, high temperature and high humidity. NMT split bearings for the power industry feature customized sealing and lubrication systems:

 

▸ Heavy-Duty Labyrinth Seal Structure – Non-contact design using centrifugal force from rotation to expel dust, coal powder, ash and contaminants. Maintains reliable sealing in dusty power plant coal handling and ash removal systems, effectively blocking external dust and moisture intrusion while preventing lubricating oil leakage.

 

▸ Contact Seal Upgrade (Taconite Seals) – For high-dust, high-contamination environments (coal conveyors, coal crushers, slag conveyors), NMT offers heavy-duty sealing solutions such as Taconite seals. SNL split plummer block housings with TXL contacting lip seals offer excellent protection against heavy contamination in power industry harsh conditions.

 

▸ Split Seals – Seals are also split for installation without shaft threading, assembled simultaneously with the bearing. Seal structures use labyrinth seals combined with skeleton oil seals, with dedicated sealing solutions matched to different power operating conditions, offering excellent dust-proof, water-proof and oil-proof penetration performance.

 

▸ Heavy-Duty Grease Solutions – Under power plant continuous operation conditions, NMT offers graded lubrication solutions: standard conditions use extreme-pressure heavy-duty grease; high-temperature conditions (induced draft fans, coal mills) use high-temperature grease.

 

5. Installation and Maintenance – An Efficiency Revolution from “Days“ to “Hours“

Installation Time Comparison:

 

Traditional power industry solid bearing: Shutdown → disassemble motors, couplings, gearboxes, frames → move shaft → slide bearing on → realign → reassemble → recommission. Typical time: 1-3 days.

 

NMT split bearing: Shutdown → open bearing housing → remove old halves → install new halves → tighten bolts → complete. Typical time: just 2-5 hours.

 

NMT split bearings for the power industry can reduce bearing replacement downtime by over 80%. Taking power plant large feedwater pump bearing replacement as an example: traditional solid bearing requires 1-3 days of downtime, with hidden costs including generation losses, start-stop energy losses and environmental penalties being extremely high; with the split bearing solution, replacement is completed in just 2-5 hours. Schaeffler split bearings can reduce replacement costs by 50%, with the entire replacement process completed inside the nacelle without removing generators or powertrains.

 

Maintenance Convenience:

 

No large lifting equipment required – Bearings are handled in sections – no large cranes needed.

 

Inspect anytime – Bearing housing can be opened for inspection without disassembly.

 

Split handling – Bearings can be disassembled into smaller components, simplifying lifting and handling.

 

No on-site adjustment – Clearances are preset at the factory – no on-site adjustment or specialized tools required.

 

Improved worker safety – Simplified installation reduces safety risks from complex disassembly work.

 

6. Quality Control – Triple Assurance of Split Precision, Heavy-Duty Strength and Seal Reliability

NMT implements a strict quality control system for power industry split bearings:

 

Heavy-duty material certification – Each batch of bearing steel undergoes impact load testing and hardness inspection to ensure performance meets power generation heavy-duty requirements.

 

Precision split surface machining – High-precision wire cutting for inner and outer ring split surfaces, ensuring concentricity and strength after assembly.

 

High-strength locking system – High-strength steel clamp rings and multiple bolts ensure split surfaces remain secure during operation.

 

Seal performance verification – Each batch undergoes dust environment seal testing to ensure sealing effectiveness under high-contamination power plant conditions.

 

Post-assembly precision inspection – Each split bearing is inspected for radial clearance, rotational accuracy and vibration after assembly – ensuring performance equivalent to solid bearings.

 

7. Stock Availability + Customization – Rapid Response to Power Plant Emergency Needs

Common power industry split bearing models (split spherical roller bearings, split cylindrical roller bearings, split tapered roller bearings) kept in stock – Covering over 80% of split bearing needs for power plant feedwater pumps, circulating pumps, induced draft fans, coal conveyors, bucket wheel stacker-reclaimers and other applications. Emergency failures receive rapid response – minimizing unplanned downtime.

 

Custom solutions available – Special bore/OD/width (standard range 55mm to 630mm, expandable), custom heavy-duty materials (carburized bearing steel/heat-resistant steel/stainless steel), special split configurations, custom sealing solutions (heavy-duty labyrinth/Taconite seals), custom clearance, split housed bearing units.

 

Rapid customization from samples or drawings – Provide old bearing samples or equipment drawings – NMT completes surveying and custom production quickly. Cost-effective replacement for imported brands (SKF Cooper, FAG, NSK, Timken) with significant procurement savings.

 

8. Lifecycle Cost Optimization – No Motor Removal, No Shaft Removal, Save Millions in Downtime Losses

Unplanned downtime of power generation equipment often costs tens of millions or even hundreds of millions of yuan. Taking power plant large feedwater pump bearing replacement as an example: traditional solid bearing replacement requires 1-3 days of downtime, with hidden costs including generation losses, start-stop energy losses and environmental penalties being extremely high. With the split bearing solution, replacement is completed in just 2-5 hours. Schaeffler split bearings can reduce replacement costs by 50%.

 

Hidden costs of cheap heavy-duty solid bearings:

 

Single replacement requires 1-3 days of downtime – hidden costs from generation losses, start-stop energy losses and environmental penalties are extremely high.

 

Disassembly of motors, couplings and surrounding components is time-consuming and may cause secondary damage.

 

Large lifting equipment rental costs are enormous.

 

Standard heavy-duty bearings last only 4-8 months under power plant harsh conditions – frequent replacement compounds the above losses.

 

Repeated disassembly easily damages main shafts, causing journal wear, outer ring rotation and shaft bending.

 

NMT split bearings for the power industry deliver “no motor removal, no shaft removal, quick bearing replacement without generation stoppage“ in power plant feedwater pumps, circulating pumps, induced draft fans, coal handling systems and bucket wheel stacker-reclaimers:

 

Downtime reduced by over 80% – From days to hours – annual unplanned downtime losses dramatically reduced.

 

No motor or coupling removal – Drive systems and surrounding components stay in place – avoiding secondary damage and realignment.

 

No large lifting equipment required – Bearings are handled in sections – reducing hoisting costs.

 

Heavy-duty steel withstands high impact and harsh environments – Carburized bearing steel and deep hardening resist impact loads – bearing service life extended by over five years.

 

Superior sealing for high-dust environments – Effectively isolates coal dust, ash, moisture and other contaminants – protects internal precision components.

 

Reduced unit energy consumption – Precision-fit operating structure greatly reduces transmission friction resistance – lowers unit operating energy consumption.

 

Extended life of配套 equipment (motors, gearboxes, couplings) – Fewer disassembly cycles – longer overall equipment overhaul intervals.

 

For thermal power plants, hydroelectric stations, nuclear power plants, wind farms and other new energy facility maintenance departments, the total cost of ownership with NMT split bearings for the power industry is significantly lower than the repeated disassembly and replacement costs of traditional heavy-duty solid bearings – what you save is not bearing price difference, but the enormous operational risk of “replacing one bearing, shutting down an entire generation line.“