From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Letter discussing the comparative construction, advantages, and issues of various industrial belts, referencing a Mr. Steadman.
| Identifier | ExFiles\Box 135\1\ scan0135 | |
| Date | 4th March 1938 guessed | |
| Rolls-Royce, Limited Page 2 there is but one layer of larger cords in the axis of tension in the belt. Both methods of construction have distinct advantages, depending upon the application in question. Our opinion on your problem is that these belts should be of Seine-Twine construction. That is what we are sending you. You mentioned that one of the difficulties you have had in British belts is that the cords have pulled loose from the rubber surrounding them. This shows poor bonding, and also I believe it will graphically illustrate to you the importance of one of our patents. I am referring to the fact that all the cords in Gates belts are soaked in latex, pure rubber, and thoroughly impregnated with rubber before they are built into the belt. This means that they become an actual part of the belt itself where the whole unit is cured. I am enclosing a little advertising folder that illustrates this point better than anything I could write. Notice the difference in bonding between the dry cords, and the ones soaked in latex! The turning over of the belt in the pulley that you have experienced would seem to indicate a twist, dip, or buckle on the inside of the belt you were using. Naturally, of course, this flaw in construction would not show up on the surface, and it would be only under operating conditions that it would become apparent. We have been able to eliminate this difficulty in our belts by building them under tension. To the best of my knowledge, there is not another belt manufacturer using this system. We have had to design special equipment to do it, but the results have been worth the effort and the expense. I might say here, Mr. Steadman, that I am not trying to "blow our own bugle" when I keep bringing up these points you mentioned and then telling you how a Gates belt will overcome them. It is just that we have been manufacturing V-belts for about twenty years, and we are accepted as the pioneers in producing this product. In all that time we've encountered, and done our best to whip, some pretty tough production problems. The difficulties you mentioned are familiar to us, and I just wanted to explain to you what we have done to overcome them. The next point I am going to bring up is that apparent slip of 5 per cent. If you have that much slip, Mr. Steadman, you are burning your belts up. It may not be apparent to the naked eye, but you can count on the friction destroying the belt internally. Or if you attempt to run a belt with from 12 to 20 per cent slip, you are really going to have some difficulties! Now to get to the belts we are sending you. We took you at your word and designed these belts to fit a different groove angle than the ones you are using at present. We also based our calculations roughly on the standards set by the Society of Automotive Engineers. We assume that these standards made an adequate guide for us to follow. | ||