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U.S. RUBBER CORP.

 

 

U.S. RUBBER CORPORATION  - 211 NORTH LOOP 336 EAST -  CONROE TX  77301     SALES 800-872-3587

KEY ASPECTS OF BELT SELECTION

CUSTOM

   BELTING   

           KEY

            POINTS

Impact Rating - The impact rating of a belt should be considered relative to the material to be conveyed, the manner in which the material is introduced to the belt and  the attention paid to absorbing the impact with  the conveyor system instead of the belt.  It is not unusual for a severe impact requirement to dictate a belt construction with considerably higher working  tensions than otherwise normal due to high levels of impact from the product carried and the system design.

 

System Take-up Capabilities - In many cases, conveyor systems have adequate take-up capabilities.  However, it is not uncommon to find a conveyor that for one reason or another does not have the take-up  space to accept normal belt elongation. In these cases, it is preferable to use a carcass construction that has a higher modulus than that normally found in Nylon tensile carcass materials. Polyester, Aramid and Steel offer increasingly higher modulus tensile members for those systems with take-up limitations

 

Since Aramid and Steel carcass belts normally require longer lead times and are not generally carried as stock items, it is sometimes more cost effective and practical to utilize higher tension Polyester plied carcass belts or Straight Warp belts in these applications.

 

Cover Selection - Cover compounds come in many varieties and are selected to be compatible with the service they are going to perform  and the atmosphere in which they are to be operating. The compounds available from U.S. Rubber are listed under the Cover Compound section of this catalog.

 

In addition to selecting the correct cover compound, it is also essential to determine the proper cover thickness required for the service desired. The following recommended cover thickness guide has been  provided for assistance in making that decision.

RECOMMENDED COVER THICKNESS

U.S. RUBBER CORPORATION  - 211 NORTH LOOP 336 EAST -  CONROE TX  77301     SALES 800-872-3587

 

KEY ASPECTS OF BELT SPECIFICATION AND BELT SELECTION

U.S. RUBBER CORP.

 

 

Transition Distance - Transition distance is defined as the distance from the center line of the first fully troughed idler system to the center line of the head or tail pulley. The distance from the pulley  to the top of the wing roll is greater than the distance from the pulley to the center roll of the idler.

 

This difference in distance creates higher tensions in the edge of the belt than t he center of the belt, which can create belt problems.  The most common of these problems are:

 

                         If transition  is too short at the head pulley

                                  Idler Gap Failure

                                  Splice failure (from the outside in)

                                  Belt folding up in the center and folding over on itself.

Minimum Pulley diameters - When a belt travels around a pulley, the outer plies of the carcass traverse a greater distance than the inner plies. If the pulley diameters are too small for the belt, the inner plies may be forced into compression resulting in ply separation and premature failure of the belt.  Minimum recommended pulley diameters for each belt specification are shown in the belt specification tables of this catalog.

Troughability  -  If a belt's transverse  rigidity is too stiff, it will not conform to the troughing idlers resulting in the inability to track the belt properly.

 

Excessive transverse rigidity is generally the result of excessive belt thickness, skim coats that are too thick or a belt that is too narrow in proportion to its thickness and stiffness.

 

A troughability chart for each belt specification is shown in the belt specification tables of this catalog.

 

Load Support -  A belt must have enough carcass transverse rigidity to ensure the proper bridging of the

 idler junction gaps, there by eliminating the possibility of belt fatigue and failure in these areas.

 

Load support information  for all belt specifications is shown in the specification tables of this catalog.

NOTE: The Rubber Manufacturers Association “RMA” has established  a limit of GAP between carrying idler rolls for troughed conveyors of 10mm.  Further, it is prudent that the overall belt gauge should be greater than 1/2 this gap.

NOTE: The minimum pulley diameter requirements for mechanical fasteners is generally more restrictive than for the belting itself. When using mechanical fasteners, wing pulleys should be 25% greater in diameter than the diameter normally recommended.

U.S. Rubber Corp. can create custom belts to suite your needs.  Our compounds are designed using the highest quality material which adds to the longevity of the belt you purchase.

 

Our sales team will work with you making sure that key areas are covered when we design your custom belting.  Some of the important areas that will be covered are listed below. 

CUSTOM BELTING KEY POINTS

U.S. RUBBER CORPORATION  - 211 NORTH LOOP 336 EAST -  CONROE TX  77301     SALES 800-872-3587

WEIGHTS OF MATERIAL (Density)

U.S. RUBBER CORP.

 

 

U.S. RUBBER CORPORATION  - 211 NORTH LOOP 336 EAST -  CONROE TX  77301     SALES 800-872-3587

U.S. FACTORY OPERATIONS IN CONROE TEXAS