Steam turbine bearings support the rotor weight and absorb axial thrust loads while maintaining precise shaft positioning within micrometre tolerances. Journal bearings and thrust bearings are lined with babbitt (white metal) that is the sacrificial wear surface, designed to be replaced periodically during overhauls.
AQ Process Systems sources and exports replacement journal bearing shells, tilting pad assemblies, thrust bearing pads, bearing housings, oil seals, and all associated instrumentation. We support both fixed-geometry (elliptical, lemon bore) and tilting-pad journal bearing designs.
Bearing clearances and babbitt condition directly affect turbine vibration, efficiency, and reliability. We ensure all replacement bearings meet OEM specifications for geometry, babbitt thickness, clearance, and surface finish.
| Component | Specification | Description |
|---|---|---|
| Journal Bearings | ||
| Journal Bearing Shells (Half Shells) | Steel-backed babbitt | Elliptical or cylindrical bore | Babbitt-lined half-shell journal bearings, the primary rotor support bearings, rebabbittable or new supply. |
| Tilting Pad Journal Bearings | 5-pad or 4-pad | LOP or LBP configuration | Tilting pad journal bearing assemblies, superior stability for high-speed and high-load applications. |
| Bearing Liners / Inserts | Babbitt (Sn-based) | Centrifugally cast | Replacement babbitt liners for journal bearing shells, centrifugally cast for uniform bond and porosity-free surface. |
| Thrust Bearings | ||
| Thrust Bearing Pads | Steel-backed babbitt | Kingsbury or Michell type | Tilting-pad thrust bearing pads, sets of active and inactive side pads controlling rotor axial position. |
| Thrust Bearing Shoes | Self-equalising | Levelling plates included | Complete thrust shoe assemblies with equalising (levelling) hardware ensuring uniform load distribution across all pads. |
| Base Rings / Carriers | Machined steel | Pad locating surfaces | Thrust bearing carriers holding the tilting pads in position, machined to maintain correct geometry. |
| Bearing Housings & Seals | ||
| Bearing Pedestals / Housings | Cast iron or steel | Machined bores | Bearing housing assemblies, machined bores, oil supply passages, drain channels, and instrument bosses. |
| Oil Seals (Bearing End) | Labyrinth or carbon ring | Preventing oil leakage | Shaft seals at the bearing housing ends preventing lubricating oil from migrating along the shaft. |
| Oil Deflectors | Brass or SS | Shaft-mounted | Shaft-mounted oil deflectors (slingers) directing oil away from the shaft and back to the drain. |
| Bearing Instrumentation | ||
| Embedded Thermocouples (RTDs) | Pt100 RTD | Embedded in babbitt face | Temperature sensors embedded in bearing babbitt for direct metal temperature measurement, the most reliable indicator of bearing condition. |
| Temperature Transmitters | 4-20mA | DIN rail or head-mounted | Signal transmitters converting bearing RTD signals to standard 4-20mA for the turbine control system. |
Parts are manufactured to OEM specifications with full material certification, dimensional inspection, and NDE documentation as required. Provide the turbine manufacturer, frame/model designation, and part number for precise identification.
The most common bearing spares are babbitt-lined journal bearing shells (wear and scoring), thrust bearing pads (babbitt wear and wipe), oil seals (leakage), embedded RTDs (sensor failure), and oil deflectors (wear). Bearing clearances are measured and adjusted during every major overhaul, shells may be rebabbitted or replaced.
Yes. Steel-backed journal bearing shells can be stripped of worn babbitt and relined with fresh centrifugally-cast babbitt. This is often more economical than new supply for large bearings. We can arrange rebabbitting service or supply new shells, whichever is more appropriate for the bearing condition and outage schedule.
Fixed-geometry bearings (elliptical, lemon bore) are simpler and cheaper but can exhibit oil whirl instability at certain speed-load combinations. Tilting-pad bearings (4 or 5 pads that pivot) are inherently stable at all speeds and are preferred for high-speed, lightly-loaded applications. We supply both types.
Thrust pads are specified by the pad dimensions (ID, OD, arc length), babbitt material (tin-based or lead-based), number of pads per set, pivot type (line or button), and levelling arrangement (self-equalising or fixed). Active and inactive sets must be ordered, both must be replaced together.
Yes. We supply Pt100 RTD sensors for embedding in bearing babbitt, both journal and thrust bearings. Sensors are supplied with the correct insertion depth, lead length, and connector type for the turbine control system. We also supply the associated transmitters and alarm/trip modules.
Share your turbine make, model, and part numbers, we respond within 24 hours.