Re: More Doubts: Pulley Drive Drum Related
I assume the carry belt is transitioned from idler trough to flat at contact with head pulley. Center of belt tension member is used as the base length. Outer edge of belt must undergo longer distance to head pulley. Given both sets of tension zones had equal elongation prior to head idler transition, outer tension zone is elongated more than center zone. Thus, higher edge strain produces edge higher stress. Higher stress = higher tension wrt to belt center. ■
Re: More Doubts: Pulley Drive Drum Related
Putting what Larry Nordell has said in a different context, if the edge tension is higher than the centre tension when the belt travels around a drum then you have a problem with the transition as this is something we absolutely try to avoid.
Next, poor transition design which result in the tensions not being equalised across a pulley face is the MAJOR cause of lagging wear on pulleys. I have encountered systems where lagging wear has translated to belt cables being broken and in fact belt broken in half in an extreme case but it does not cause longitudinal rips.
Cheers
Colin Benjamin
Gulf Conveyor Systems Pty Ltd
www.conveyorsystemstechnology.com ■
More Doubts: Pulley Drive Drum Related
Hi all,
Sorry for the 3rd post in as many days but this forum is helping me with a LOT of stuff. Big shout out to Mr Colin Benjamin and Mr Lawrence Nordell.
Anyway my questions are
1) I know that this is true but cannot figure out why. - Why is belt edge tension higher than the center tension as it goes around the drive drum?
2) Friction is a key reason why the drive drum can move the belt around the system but out of curiosity is it possible that pulley wear can cause elastomer damage? Like rips or cracks on the belt. My guess is no but input is appreciated.
Thank you
-Sidd ■