was performed on a specimen of each material, while the two other specimens were set 

 aside to be tested after exposure to the working environment for six months and one year. 

 A comparison of the three load-deflection curves of each material would then show the 

 deterioration of the material as a result of the exposure. 



When performing these tests, the outer rubber covers were not stripped away since in 

 actual practice, the marina owners wouldn't do this before using the belt. 



The failure criteria used was either: 



1- When either the top or bottom rubber cover separated from the inner 

 synthetic carcetss fabric or 



2- When the synthetic carcass broke, 

 whichever occurred first. 



The particular tensile test specimen's geometry was obtained after consideration of Figure 



802.1 in the Conveyor and Elevator Belt Handbook. This book is published by the Rubber 



W 

 Manufacturers Association, located in Washington, D.C. If one calculates the ratios of -j-, 



R R 



— and — they wiU be constant regardless of the die number. Since a 2-inch-wide belt was 



decided upon for testing, making A=2.0, the other dimensions came out as shown in Fig. 1. 



The second phase wets to test the strength of various forms of connections. Five concepts 



were used. 



In order to eliminate any steel in the connection, a fastening concept was designed that 

 used only chemical compounds. It is shown in Figure 2 and is called the first concept. The 

 two compounds used were cold vulcanizing compound and Flexane 80 putty. This 

 particular geometry was chosen for a number of reasons: 



1- The belt is easily bent into loops. 



2- Looping is the simplest way to bring the belt through shackles and rings. 

 Therefore, this would be a very simple and cheap way to fasten the belt to 

 itself if it was found that the joint formed would have sufficient load- 

 carrying capacity. 



18 



