Angel hairs and tube abrasions are the nemeses of cap and closure conveyance. On Apr 1, 2009 Shrikant Dhodapkar (and others) published “Understanding Bends in Pneumatic Conveying Systems” in Solids Processing. The document is widely available online. The article has excellent graphics on various bend’s styles designed to minimize abrasions. This is nothing new to us. We have made expanded bends for decades out of CAB.
The bend design slows down the velocity of caps and changes their orientation within the air stream. It helps eliminate streamers and dust.
We make such bends to order and offer a wide variety of bubble bends.