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Rubber Ron’s Report — The World is Changing
 In August 2004 the price increases on rubber compound, fabric and PVC resins started. This was just before the 2004 NIBA National Convention. When I attended the convention in Oct 2005 prices on domestic conveyor belt had increased by 26% in a 14 month time frame! What is amazing to me is that within two weeks of the convention three major rubber companies announced another 6% price increase, some with a 4% surcharge for energy prices.
We all understand price escalation based on shortages of raw material and supply and demand. The fundamental change that is occurring however, is something that has never happened in our industry, no more prepaid freight on single slabs.
Some companies have increased prepaid freight to 20,000 pound orders, others at a $15,000 price point. Another costly increase is handling fees up to $225 per shipment. I forgot to mention common freight surcharges at 2% to 6%.
I believe these changes will continue in the industry. It will start to trickle down to the distribution level resulting in higher costs to all.
Tech Notes - Belt Tension Belt tension must be tight enough:
- To prevent slippage between the drive pulley and the belt, and
- To force the belt to conform to the crowned pulleys
Slippage will cause excessive wear to both drive pulley lagging and the belt. Further, an excessive heat buildup on the drive pulley lagging can result in rubber reversion. Reversion is the softening of vulcanized rubber when it is heated too long or exposed to elevated temperatures. It is the deterioration in physical properties, and frequently results in tackiness. One the pulley lagging has reverted, it frequently will offset onto the bottom side of the conveyor belt which will then distribute the reverted rubber throughout the slider or roller bed of the system. The resulting tackiness between the bed and the belt will certainly drive current consumption up, can actually result in a stalled system, and can cause severe tracking problems. (NOTE: the bottom cover can also revert)
If belt tension is not high enough to force the belt to conform to the crown on the pulley, then poor tracking is an almost certain result. A belt which does not conform to the crown cannot be guided by that crown.
This suggests a convenient rule of thumb for determining "proper tension". Simply stop the conveyor and depress the belt at the end of the crowned pulley. There should be no play between the belt and the crowned pulley. If there is play – increase the tension. Once proper contact is made between the edge of the belt and the end of the crowned pulley, that crown will be guiding the belt. Tracking will be improved, and in all likelihood sufficient tension will be on the system to avoid slippage at the drive pulley. Obviosly, if slippage still occurs, increase the tension further.
For more information please refer to Rubber & Plastics, Inc. website
www.conveyorbelt.com - Belt Engineering & Technical Data.
Tech Notes excerpts taken from Tracking Monograph, Georgia Duck and Cordage, 2/11/1980
Product Showcase
This belt was fabricated with four rows of ½" x ½" chevrons, 20" wide by 18" long.
 
330' of 96" wide belt
- Longitudinally spliced as a short delivery time alternative to factory belt at 180 day delivery time
- Used on recycling equipment
Featured Accessories
48” & 60” Replacement Impact Bars
3” height x 4” width with 3/8” blue UHMW top. 4 bolts provided with 48” bar, 6 bolts provided with 60” bar.
Skirtboard Rubber
 
Packaging: 50 Foot Rolls
Specifications: Blended SBR/NR slit sheet, Plate Finish
Style SK60: 60 Duro hardness (Shore Durometer A)
General Properties of Skirtboard Rubber:
- Excellent abrasion-resistance
- Excellent weather-resistance
Polymer: Styrene-Butadiene and Isoprene Rubber
Natural
Color: Black
Common Name: Skirtboard Rubber
ISO/ASTM Designation: SBR/NR
Comic and Quote for Winter 2006
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