Rudder Bearings with Rollers BOTTOM RUDDER BEARINGS
TYPE 41000 Lower Roller Bearings for Rudder Shaft Diameters 30mm - 350mm
The 41000 series Jefa Rudder Bearings are the first type of roller bearings that were produced by Jefa Marine. In the past 30 years, more than 25,000 of these bearings have been produced. This bearing is typically suitable for GRP or wood core cruising yachts where a light revolving and backlash free rudder system is required that will not be stretched to the limits as on racing yachts. The bearing is also perfect as hull bearing for skeg rudders as the skeg will prevent the shaft from bending. Due to the high tolerances between the shaft and bearing, it has to be glassed in combination with the shaft present in the yacht. For one-off projects this is mostly not a problem. For production environments, Jefa Marine can supply a dummy shaft (a rudder shaft without the part that normally sticks out beneath the hull). This bearing should not be used in aluminum and steel hulls. It’s better to use the 43000 series Self-Aligning Bearings for these types of hulls.
Rudder Shaft Diameter (30mm - 350mm)
The bearing can be sealed by a rudder tube or double lip seal inside the top register.
TYPE 4S000 - SELF ALIGNING Self-Aligning Lower Roller Bearings for Rudder Shaft Diameters 40mm - 299mm
The 4S000 series bearings are suitable for GRP and wood core cruising and racing yachts. This bearing type combines a very simple installation with a very smooth operation under all circumstances as the bearing will always be aligned to the rudder shaft. The bearing consists of an aluminum outer housing with an inside sphere turned out. A one piece delrin ball is located in the sphere and is sealed to the outer housing by an O-ring. The inner housing is pushed inside the delrin ball and also sealed with an O-ring. This construction creates a watertight situation between the rotating inner housing and the fixed outer housing. The inner housing will always have one set of rollers. It’s therefore important to check that when the bearing diameter is above 90 mm, and the maximum working load isn’t exceeded. If the calculated working load is above the maximum working load, one should choose bearing type 43000.
Rudder Shaft Diameter (40mm - 299mm)
The bearing can be sealed by a rudder tube or double lip seal inside the top register of the inner housing, or for maximum security a rudder tube in the top register in the outer housing.
TYPE 43000 “Heavy-Duty” Self-Aligning Lower Roller Bearings for Rudder Shaft Diameters 41mm - 300mm
The 43000 series bearings are suitable for all types of hull material. This bearing type combines a very simple installation with a very smooth operation under all circumstances the bearing will always be aligned to the rudder shaft. The bearing consists of a heavy duty aluminum outer housing with an inside sphere turned out. A two-piece delrin ball is located in the sphere. The inner housing is pushed inside the delrin ball. Above 79mm, two sets of rollers are mounted to achieve a very high working load. As the delrin ball is mounted in two parts, the bearing is not watertight between the outer housing and inner housing, so a tube has to be used in the top register of the outer housing to achieve a proper sealing.
This bearing is normally used in applications where the working load of the 4S000 type bearing isn’t sufficient. For aluminum hulls this bearing can provide the perfect solution: the outer housing can be welded into the hull, providing a very strong and fast installation and also saving a very expensive big tube. Rudder Shaft Diameter (41mm - 300mm)
TO ORDER VISIT WWW.PYIINC.COM OR CALL 425-355-3669
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