Selecting_Belt 选择皮带.pdf

Selecting the Proper Conveyor Belt Low Tension Snub T 1 T 2 Arc of Contact Head Pulley + T 1 T 1 T 2 T 3 Geared Tandem Drive Single Pulley Drive + Arc of Contact Primary Pulley Arc of Contact Secondary Pulley Selection of the best conveyor belt construction . . .carcass . . . and cover . . . is based on the specific requirements of the particular conveyor system, the material being conveyed and the conditions under which it must operate, as well as its “cost effectiveness.” Some primary considerations involved are: 1. Maximum Operating Tension (Working Tension) 2. Minimum Pulley Diameters 3. Troughability, Transverse Rigidity 4. Load Support 5. Transition Distance 6. Impact Rating 7. Covers, and 8. Cost per unit handled Should this belt be a replacement belt, an examination of the old belt and a thorough study of the conveyor system itself can pay off in longer belt life and reduced maintenance cost. Questions, such as the following, should be raised: 1. How did the old belt fail? 2. How long did it last? 3. What type carcass? Cover gauge? 4. Have operating or environmental conditions changed? 5. In view of the past history, what changes in belting specifications are mended? Maximum Operating Tension Maximum operating tension is generally charac- terized in terms of pounds per inch of width and should be matched as closely as possible to the PIW working strength of the belt constructions under consideration. The working strengths of specific ia Duck belt constructions can be found in the appropriate ia Duck brochure or belt specification data sheets. Maximum operating tension is a prime consider- ation in selecting the right belt . . . this being the highest tension occurring in any portion of the belt, on the conveyor system, under operating conditions. The conveyor system applies an appropriate amount of power to the belt in order to drive the belt at design speed. This power must be sufficient to accelerate and drive the empty conveyor, to move the material