Standard Belt Cross Section Sizes
The English section O / 3L / Z is 3/8" or 0.44" wide. The A / 4L is 1/2" wide by 5/16" thick. The B / 5L is 21/32" wide and 3/8" thick. The C section is 7/8" wide and 17/32" thick. Section D is 1-14" wide and 3/4" thick.
Section E is 1-1/2" wide and 7/8" thick. The dimensions for section 3V are 3/8" (width) and 5/16" (thickness). Section 5V is 1/2" wide by 13/32" thick. The 8V is 1" wide and 7/8" thick.
Fan Belt Dimensions (Metric Section)
The SPA is 13 mm wide x 8 mm thick while the SPB is 17 mm wide x 11 mm thick. The SPC is 22 mm x 18 mm thick. The SPZ is 10 mm x 6 mm. The 5 mm measures 5 mm x 3 mm, while the 6 mm is 6 mm x 4 mm. The 8 mm is 8 mm wide x 5 mm thick.
The 10 mm belt is 10 mm wide x 6 mm thick. The 13 mm is 13 mm x 8 mm. The 17 mm is 17 mm wide by 11 mm thick. The 20 mm measures 20 mm x 12.5 mm. The 22 mm fan belt dimensions are 22 mm x 14 mm. The 25 mm belt is 25 mm x 16 mm and the 32 mm is 32 mm x 20 mm.
Section H is 12" thickness x .063" rib pitch, while J is .14" thickness x .092" rib pitch. The specifications for the L section are .38" thickness x .185" rib pitch. For M it is .51" thickness x .370" rib pitch; for PJ it is 3.6 mm thickness x 2.34 mm rib pitch.
The PK is 4.5 mm thick x 3.56 mm rib pitch. The PL is 6.6 mm thick x 4.7 mm rib pitch. The PM is 12.8 mm thickness x 9.4 mm rib pitch.
Fan belt dimensions aside, the material the belt is made of makes a big difference. Neoprene is synthetic rubber designed to protect the belt from ozone, sun and fluctuating weather conditions. It is compatible with oil and different chemicals. It doesn’t get damaged by twisting.
Polyurethane refers to several materials known for their durability and abrasion resistance. Polyurethane and urethane are the same.
Other belts come with reinforcements. Among the most popular choices are fiberglass polyester, Kevlar and steel. Fiberglass is known for being resistant to extreme weather temperatures. Kevlar is renowned for its tensile strength and light weight. It also has high chemical resistance and is resistant to flame.
Stainless steel or steel wires are used in many industries for various applications. Polyester is usually combined with glass and other materials to give it additional strength.
Fan belt dimensions will vary per manufacturer and application. Also note there are other belt types like ribbed, flat and timing belts.