Introduction
This document provides technical specifications and guidelines for water-lubricated rubber bearings used in marine applications. The primary lubricant is seawater, which offers cost-effective and efficient lubrication compared to traditional metal bearings.

Specifications
Rubber bearings offer several advantages over metal bearings, including a low friction coefficient, high wear resistance, vibration reduction due to rubber elasticity, and the ability to handle high peripheral speeds and radial loads. The bearings are designed with deep longitudinal grooves to accommodate bidirectional shaft rotation.

Materials
The outer casing of the bearings can be made from high-quality brass or polyamide resin with 40% mineral reinforcement. The inner lining is made of soft nitrile black rubber without sulfur, characterized by a density of 1.23, hardness of 70/75 shore, tensile strength of 22MPA, elongation at break of 225%, and a compression set of 13.5% after 22 hours at 70°C.

Lubrication and Maintenance
Seawater forms a thin lubricating film between the shaft and rubber, reducing friction. It is crucial to avoid dry operation and contact with harmful substances like grease or oil. The water also helps dissipate heat, maintaining the bearing temperature below 50/60°C. Proper clearance between the shaft and bearing, as well as adequate water circulation, is necessary.

Installation Guidelines
1. Shafts should be made of stainless steel and be smooth with h9 clearance.
2. Bearings should be hand-pressed into place to avoid mechanical damage.
3. Ensure water flow grooves are unobstructed.
4. Avoid heating the rubber during installation.
5. Check shaft alignment post-installation.
6. Store bearings in cool, dark places.

Technical Data
Table Z provides clearance tolerances based on shaft diameter. Table X specifies the minimum and maximum peripheral shaft speeds (0.25 to 10 m/sec). Table Y outlines the minimum water flow required based on shaft diameter.

Product Dimensions
The document includes detailed tables listing dimensions for various bearing models, both in metric and imperial units, suitable for different shaft sizes.

Contact Information
For further inquiries, contact Eliche Radice at their Milan office.