Gearbox Bearings

Malloy has gearbox bearings in stock for over 30 different gearboxes in all major turbine platforms. This includes the aftermarket standard of **Black Oxide** bearings as well as upgraded **Super Tough** bearings that can greatly increase bearing life in Wind.

Malloy has a large selection of gearbox bearings in stock. There are several sets of High Speed and Intermediate Shaft bearings in stock for many gearboxes, as well as complete bearing sets for select kW and MW class gearboxes. Our inventory includes but is not limited to the following gearboxes:

Winergy
3505 4300 4320 4390 4410 4411 4419 4431 4435 4456 4458 4481

Monventas
308 310 312 1100 1400

Hansen
EH552 EH601 EH802 EH803 EH804 EH811 EH851 EH853

Bosch RexRoth
GPV-441 GPV-442 GPV451 GPV-453 GPV-455 GPV-457

Nanjing (NGC)
FDM FDMD FDMX FDM2

GETS
7GA87Cx 7GA87Ex 7GA89Ax

Ishibashi
Mitsubishi M1000A gearbox Mitsubishi 2.4MW gearbox

Zond
750kW gearbox

Table of bearing materials available for wind turbine gearboxes

Wind power gearboxes are speed increasers. The turn the slow speed, high torque rotation of the blades into high speed, low torque rotation that drives a generator to produce power. The most common gearboxes installed in wind have 1 stage of planetary gearing on the Low Speed side, and 2 stages of helical gearing as they progress to the High Speed side. The image above depicts this construction.

Figure 1: This is the most common HSS bearing configuration with 2 CRB's and 1 thrust ball bearing.

Figure 2: This is the next most common HSS bearing configuration with 1 CRB and 1 tapered bearing set.

Figure 1: This configuration uses 2 NJ type Cylindrical Roller Bearings.

Figure 2: This configuration uses 2 Cylindrical Roller Bearings and a thrust ball bearing.

Figure 3: This configuration uses 1 Cylindrical Roller Bearing and a set of Tapered Roller Bearings.

There are several different bearing configurations used in LSIS applications. The most common consists of 2 CRBs either full compliment (NCF) or caged (NF). Other designs uses a CRB on one end and either a TRB set or an SRB.

Gearbox manufacturers have explored the use of several different bearing types in the planetary position. In the late 1990's and early 2000's many bearing manufacturers suggested using spherical roller bearings (SRB) in the planetary position. They learned that SRB's didn't perform to expectations and started exploring other options. Since then the most common designs included either cylindrical roller bearings (CRB) or tapered roller bearings (TRB). The CRB designs have included 3 to 4 rows of cylindrical roller bearings, often a full compliment NNCF type bearing. The TRB designs consist of 2 tapered bearings set back to back within the planet gear. The most recent trend in planet bearings is to use a bearing that consists of only the inner ring, roller set and cage, and the bore of the gear is highly finished and acts as the outer ring of the bearing. This design offers an increase in capacity for the same bearing envelope.

In an effort to increase drivetrain reliability some of these older, problematic designs have upgrade options. There are CRB upgrade options for gearboxes that originally had SRBs. The newest upgrades even include an integrated race bearing to replace the NNCF bearing designs

The most commonly installed bearing found in the planet carrier position is a full compliment cylindrical roller bearing (CRB). These are very well suited to this position as they turn very slowly and are subjected to high loads. Alternatively, some gearbox manufacturers use tapered roller bearings in this positions.

Gearbox Bearings

Super Tough Bearings

Black Oxide Bearings

Through Hard vs Case Hard Bearings

Bearing Types