Although most tape and reels are safe to overlook since they are suiting to the component type, size, and quantity, they can vary in some specs and sometimes be of concern. Reel size can become important when picking out specific feeder types or loading them onto a pick-n-place machine as certain reel sizes and part types may have to be on certain sections of the machine.
For highly efficient pick-n-place processes, various reel widths and part advances will be strategically placed in the machine as a way to make the placement process more efficient, typically through a dedicated software program, which saves time when parts are being placed on the board. Saving a microsecond per part placement will add up when placing thousands or millions of parts per day.
Reel Width:
Width of the reel, some SMT feeders and machines can only handle reels up to a certain width. Common reel widths are 4mm, 8mm, 12mm, 16mm, 24mm, 32mm, 44mm, & 56mm. Reel width is dependent on component size, weight, and also how much protection the component needs.
Reel Diameter:
Diameter of the reel, commonly referred to as “reel size”. Similar to width, some SMT machines can only handle reels up to a certain diameter. Reels are commonly 7’‘, 13’’ or larger. Although typically not as important of a specification, some machines or subsets of a machine can only handle the “mini-reels” (7’’ diameters). Ordering the correct diameter of reel can avoid costly downtime and unnecessary re-reeling of a part before production.
Pitch:
Pitch between successive cavity centers on the tape, sometimes referred to as the “advance”. Basically, pitch refers to center of one part to the center of the next part. The industry standard is measured within 4mm increments (4mm, 8mm, 12mm, etc.) from part center to part center. This spec is typically irrelevant, as modern machines should adjust for this. This will have to be adjusted in the SMT program when changing part advances unless the feeders have auto advance detect sensory.
Paper Vs Emboss:
Paper is a thin pressed cardboard like material, where emboss is a very thin plastic type material. Component feeders usually are able to accommodate either one.
Tape and reel specifications for a specific part can be found in the datasheet, under Documents & Media on the DigiKey product page, or on the manufacturer website. If reel information is still not found for a part you are ordering, please reply to this post and we can find out for you.
For more information on Digi-Reels, see below:
https://forum.digikey.com/t/details-about-digi-reels/1303
For more information on carrier tape types, see below:
https://multimedia.3m.com/mws/media/611487O/choosing-carrier-and-cover-tape.pdf
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