Monthly Archives: September 2012

Telebelt Belt Tracking Troubles? Wearing out your rollers?

A few questions recently came in from a customer concerning belt tracking and wearing out of rollers on their TBS 130. These issues and resolutions apply to all ”active feeder” model Telebelts - TB 80, TB 110, TB 130, TB 600, TBS 130 and TBS 600. Let’s go over their issues, and how to fix them.

Issue 1: On the feeder belt, there are 2 gangs of 3 roller sets,  and for some reason, we are having to change out 2 of the three sets every 2 weeks (the belt is wearing on the shafts that the rollers are on). We checked our other two belts and they are not having this issue.

Resolution: The feeder triple rollers are directional.  Each side roller is set at a slightly different angle. Make sure the end with the widest (lowest) offset faces the hinge.  In other words, the wide offsets face each other (see left).  If mounted in reverse, only the narrow set contacts the belt, and I can see the possibility of the belt being pulled down to the shaft, especially with this thinner type of belt. The photo looks like the belt flattens out, going left to right. If that is the case, the triple roller is in  backwards.

 

Issue 2: On the main belt, when you have the boom extended, the belt tracks with no problems (stays centered on the roller). When you retract the boom, upon getting to the last two sections, the belt tracks to one side of the roller and rides there until you extend it back  out. We checked the belt tension and its sitting at 1,200 psi.

Resolution: Don’t over-tension the belt. The manual calls for 1,500 – 1,800 psi on the feeder. I instruct operators to go to the low end; 1,500 psi. Training (belt alignment) of the pulleys, with the boom extended, is very difficult. In this position, the head pulley of one section is very close to the tail pulley of the next. A centered belt can mean the pulleys are working against each other, or adjustment is correct – There is no way of telling.

DO NOT ATTEMPT ADJUSTING A BELT, OR CLEANING OF ROLLERS AND PULLEYS, WHILE THE BELT IS MOVING. Shut the belt off and push the E-Stop to make the adjustments or do the cleaning.

Never train pulleys unless the belt tension is first confirmed. A loose belt wanders on the pulleys, and attempts to train it will not succeed. Again, I suggest 1,000 psi, which is the low end of the 1,000 – 1,200 specification for the main belt (the slightly reduced tension yields longer splice life). Train the pulleys with the boom retracted as far as possible. Telebelts use crowned (tapered) pulleys. They are self-training, since each half of the belt is trying to run off the end of the pulley. This allows us to go without side idlers, which we have no room for . When the belt gets loose, the side that contacts harder pills the belt to that side.  Again, tension the belt first. This will take care of training problems.

A properly tensions and trained belt will not go out of alignment. Training is usually only required if a pulley is replaced. Grout buildup on the pulleys can also cause alignment problems, so keep them clean.

Issue 3: After adjusting the tension in all of our belt, the belt tracks fine when you extend the boom past the first section (it stays centered on the rollers without any problems), but if we have the belt rolling without extending anything, the belt seems to run on the one side of the pulley. Also, when you bring the boom back in and reach the second section, it moves over.

Resolution: When extending and retracting with the belt stopped, the belt can wander on the pulleys, When running, it should stay centered. Extend arm 2 partially and check the adjustment of the heel of arm 2 and the head of arm 1. If they are ok, extend arm 2  enough to gain access to the heel pulleys of 3, 4, and 5 since they are still bundled together. Check them and then check the remaining head pulleys.

DO NOT attempt to train the 12″ main drive pulley with the large adjustment bolts. This is a straight pulley, not crowned. Adjustment is made on the 5″  roller at the heel of arm 1. If the belt is centered on it it will be centered on the drive pulley.