21 mm vs 20 mm timing belt width. Can they be interchanged?

[Life is a bowl of problems]

I would like to understand why some same pitch timing belts and pulleys are available in 20 and 21 mm widths and if there is any reason I should not use a 20 mm belt on a 21 mm wide pulley.

For example: 8MGT-416-21 and 2200-8MGT-20

 

[drawoh]

Life is a bowl of problems,

The belts are different from each other. This is not just the width.

Is this your design, or are you replacing the belt from someone else's design? If some else specified this, maybe the material mattered more than the width. Have you looked up the torque and power tables for the belts?

 

[Life is a bowl of problems]

Over time we have accumulated a variety of purchased parts we use on the equipment we manufacture. We always make an effort to draw from this pool of parts when updating designs or when creating new designs. There are times when we have 21mm wide pulleys available in our system with the desired pitch and tooth number and also a 20 mm wide belt but not sure if we should use these together or define a new belt or pulley that matches in width.

 

[3DDave]

8MGT-416-21
Poly Chain Carbon Belt
Tensile Cord Carbon
Core Material Polyurethane
Fabric Cover Blue Nylon

2200-8MGT-20
PowerGrip GT2 Belt
Tensile Cord Fiberglass
Core Material Chloroprene
Fabric Cover Nylon

Looks like different tooth form, different belt strength, different belt material which means different chemical resistance and durability, the latter usually a trade-off for cost and operating losses.