One of the most frequently asked questions is,” how long will a rubber belt last?” That question is very much like asking, “how far is up”. No one can answer this question honestly.

The fact is, that most rubber belts are not replaced because they can no longer shrink cloth satisfactorily. Rubber belts often suffer damage caused by accidents, improper operation and/or maintenance, cloth width considerations, or are taken out of service simply because they have been reduced in thickness to some arbitrary minimum useful thickness. Rubber belts can continue to be kept in use regardless of thickness, as long as they continue to provide required pre-shrinking capability.

Other major factors are: types of fabrics being processed, types of finishes applied to the cloth, machine operator skill, quality of water used to cool the rubber belts, excessive heated cylinder surface temperature, excessive compression (squeeze) of the rubber belt, improper tension applied to the rubber belt, poor condition or adjustment of rubber belt cooling water sprays or felt doctor, incorrect adjustment of belt lateral limit rollers, insufficient frequency of belt re-surfacing (grinding), prolonged and/or frequent stoppage of the shrinking machine while heated cylinders are at operating temperature.

As is evident from the above, there are very many factors, aside from the actual rubber belt quality, which may exercise a significant impact on belt longevity. To suggest a specific useful life for any rubber belt would be less than honest.

What we do know, is that DUNLINE Rubber Belts will measurably outlast any other belt when used under the same conditions to process the same goods.

We can report that according to data provided by DUNLINE Customers, Dunline 67 mm (2 5/8 inch) thick belts, shrinking 480 gr/sq.mt. to 500 gr/sq.mt., 100% cotton denim cloth with potential warp shrinkage of 16% +, commonly have a useful production life of from 11 million to 14 million meters.

Producers of lightweight, low shrinkage potential, 100% cotton or cotton/polyester blends, commonly report from 15 million to 20 million meters of productive life.
This alone reflects the vast range of rubber belt life expectancy, however operating and maintenance proficiency can affect these figures in a substantial way, either positively or negatively.

There is no substitute for good training. Well trained shrinking machine operators and maintenance personnel can often bring about rubber belt longevity increases of 20% to 30%. Rubber belts used to shrink high potential shrinkage goods such as 100% cotton denim having a weight of 14 oz/sq.yd. can usually continue to shrink such goods without any problem, even when the rubber belt has been reduced in thickness down to about 1-3/4 inches (45 mm).
Lightweight goods having a potential warp shrinkage of up to 6% can be shrunk using rubber belts having a thickness of only 1-1/2 inch (38 mm), or less.

When rubber belts are reduced in thickness to 50 mm or less, belt tension must be increased to ½ inch per 12” (13mm per 305mm of rubber belt length, in order to continue to provide maximum cloth warp shrinkage capability and cloth appearance.  Note:  Rubber belts thicker than 2 inches (50mm) should operate with belt tension adjusted to ¼ inch (6mm) of belt stretch per each 12 inches (305mm) of belt length.  Please refer to specific instructions for rubber belt tension adjustment procedure.

DUNLINE is the only Rubber Belt manufacturer with the Technical know-how to assist customers and train their personnel to take advantage of the unequalled quality of DUNLINE Rubber Belts.