50 Useful Information Key to Symbols Fabric Designation Coefficient of Friction (Belt to Slider Bed or Rollers) Belt Length Belt Speed in Feet per Minute Maximum Product Weight on Belt at Any One Time C - Center to Center distance (In.) D - Diameter of Drive Pulley (In.) d - Diameter of Tail Pulley (In.) G2 - Load per Hour (Lbs.) L - Belt Length (In.) P - Product Weight (Lbs.) RPM - Revolutions per Minute S - Speed, Ft. per Minute (FPM) For a pulley system with no snub pulley: L = ( D + d × 3.1416 ) + 2C 2 S = D × RPM × .2618 × 1.021 When load is known by pounds per hour or tons per hour: P = G2 × C (Ft.) S × 60 (minutes) Poly/Nylon Nylon/Nylon Poly/Poly PN NN PP Carcass U.S. EP PP EE Metric Belt Steel or Aluminum Slider Bed Metal Rollers FS Pulley Side Bare Duck or BB Side Cover on Pulley Side .30 to .35 .20 to .25 .50 to .55 .05 to .10 .05 to .10 .05 to .10 Calculating Length of A Roll of Belting Add together the diameter of the roll and diameter of the hole in inches and divide the result by 2. Multiply by 3.14 and by the number of coils in the roll. This gives the length in inches. Divide by 12, and you will have the approximate number of feet in the roll. Determining Belt Length When Snub or Takeup Pulleys Are Present Steel Tape Measurement - STM, also known as the I.C. or inside circumference, is a common method where the takeup is placed in a position that allows for easy installation and adequate takeup. The steel tape is run through the system on the same track the belt would run. Care must be taken to make sure the tape touches all pulleys. The belt may be tracked to one side or removed to accomodate this method as the tape must touch only the pulleys and not the belt for an accurate STM measurement. Calculating Length of A Roll of Endless Belting Net Endless Length (NEL) - From an existing belt, this measurement is made by placing the ENDLESS belt to be measured on a table or floor. A mark is made on the cover and corresponding mark on the table or floor. The belt is rolled forward until the mark comes back. Place another corresponding mark on the table or floor. Move the belt aside and measure the distance between the two marks. This measurement represents the NEL measurement or Net Endless Length. Many considerations of factors determine the selection of the best belt for the job. The following information will aid you in this process. Assistance is available for the asking.