Aqualine provides a high precision range of water lubricated marine rubber bearings designed and manufactured for propeller shafts in stern tubes or struts in all inboard engined marine vessels.

The exceptional properties of rubber as a bearing material combined with the high performance of their hydrodynamic water wedge design ensure that Aqualine bearings are the choice for reliable and maintenance free operation. 
The design consists of a rubber lining bonded to a shell of composite material. The straight fluted design allows maximum resistance to deterioration.

Aqualine provides a high precision range of water lubricated marine rubber bearings designed and manufactured for propeller shafts in stern tubes or struts in all inboard engined marine vessels.

The exceptional properties of rubber as a bearing material combined with the high performance of their hydrodynamic water wedge design ensure that Aqualine bearings are the choice for reliable and maintenance free operation. 
The design consists of a rubber lining bonded to a shell of composite material. The straight fluted design allows maximum resistance to deterioration.
 

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Lining Materials
The standard lining material is a synthetic nitrile rubber of 65 Shore "A" hardness. This tough compound is known for its resilience and its high oil and abrasion resistance. That is the loss of rubber due to hard particles or hard protuberances that are forced against and move along a solid surface. It is suitable for most applications up to 100 deg C. And a range of alternative compounds are available for other similar applications too.

Shell Materials
In Silverline the shell is composed of a brass. Which is prone to electrolytic corrosion. Therefore if electrolytic corrosion could be a problem, a non-metallic shell material e.g. a composite shell is used such as Aqualine. 

The Aqualine bearing material of construction is a reinforced composite, which offers suitable strength for marine applications. The composite shell is light, impact resistant, whilst having negligible water absorption it will not bind to metal housings or delaminate during installation or maintenance. Outer shell diameters can be machined to incorporate flanges, collars and most other required design features. 

Shaft Clearances
The techniques used to bond the shell and rubber ensures strength of bond that matches the strength of the rubber itself. That is this bond will not be the weakest link in the chain. 

Bores of all bearings are machined with correct clearances to suit shaft diameters. A standard clearance of 0.1mm per 100mm with tolerance - 0.001~ 0.004 inches per inch of shaft diameter is specified. This allows for any dimensional change due to water absorption to be properly managed and still give sufficient running clearance