INTRODUCTION
A propeller shaft bearing (also known as a Propeller Shaft Bearing or Stern Tube Bearing) is a critical component of a vessel’s propulsion system. It provides guidance, radial support, friction reduction, and vibration damping for the rotating propeller shaft as it operates continuously in seawater, under varying loads and contaminants.
Despite its small size, the bearing plays a decisive role in shaft durability, noise level, propulsion efficiency, and overall service life of the drivetrain.
STRUCTURE OF A PROPELLER SHAFT BEARING – KEY VARIANTS MANUFACTURED BY ANH TRÍ TUỆ
Propeller shaft bearings are manufactured in several designs depending on vessel configuration and operating conditions:
A steel/alloy outer sleeve combined with an inner NBR rubber layer featuring longitudinal lubrication grooves.
One-piece rubber tube or rubber bonded with a plastic connector featuring longitudinal lubrication grooves.
All variants incorporate water-lubrication grooves inside the bore to promote hydrodynamic film formation.
WORKING PRINCIPLE
Propeller shaft bearings operate based on water lubrication:
This mechanism ensures stable operation even in harsh marine environments, especially for fishing vessels and cargo vessels.
ROLE OF THE BEARING IN A VESSEL’S PROPULSION SYSTEM
SELECTING THE PROPER BEARING FOR EACH VESSEL TYPE & OPERATING CONDITION
|
Vessel Type |
Operating Conditions |
Recommended Bearing Type |
|
Fishing boats Wooden boats Near-shore vessels |
Sand/mud in water, high vibration, shaft misalignment, difficult maintenance |
Rubber bearing with metal shell; Rubber bearing without shell |
|
Tugboats Service vessels Workboats |
Heavy loads, strong vibration, frequent throttle changes |
Rubber bearing with metal shell; Phenolic bearing |
|
Cargo ships River–sea transport vessels |
Stable load, long operating hours, long service life required |
Composite bearing; Phenolic bearing |
|
Patrol boats Coast Guard Navy-type vessels |
High speed, strict shaft stability requirements |
Composite bearing |
|
Yachts Speedboats High-speed leisure craft |
High speed, small diameter shafts, smooth/quiet operation |
Rubber bearing without shell; Rubber bearing without shell with plastic connector |
|
Large vessels (container ships, etc.) |
Heavy load, continuous operation |
Composite bearing; Phenolic bearing |
PROPELLER SHAFT BEARING PRODUCTS OFFERED BY ANH TRÍ TUỆ
WHEN SHOULD A BEARING BE REPLACED?
A propeller shaft bearing may be a small component, but it plays a crucial role in the reliability and efficiency of a vessel’s propulsion system. Understanding its structure, operating principle, and selecting the proper bearing type for each vessel ensures smoother operation, reduced vibration, lower fuel consumption, and longer shaft–propeller lifespan.
With extensive experience supplying bearings for fishing vessels, service boats, transport vessels, and high-speed craft, Anh Trí Tuệ offers a full range of materials and can manufacture bearings to any required dimensions—optimizing durability, smoothness, and service life for every propulsion shaft configuration.
