Belt Cupping
The only way your going to help the client is going be using a forced air heating system to extend the life of the belt If the transfer points are enclosed or should be if a forced air furnace is employed. ■
Checking Back
Dear Mr . Sharp,
you might want to have the TC and BC materials thoroughly checked identical chemical and physical properties.
Described effect has been seen with belts where the materials were different.
Kind regards
R. ■
Re: Belt Cupping
Mr Sharp
That's an interesting problem. A couple of observations that come to mind are:
- new belts will often sit higher in the trough
- given that it is a steel cord, the stiffness causing the cupping is probably coming from the covers, at least in part. As the covers wear, the lateral rigidity of the belt should reduce. Hence, you may find that the problem will gradually decrease. ■
Belt Cupping
One of our clients has experienced a conveyor belt cupping issued during cold temperature operations. Here is a description of the issue:
On two (2) 36" (915 mm) BW belt conveyors when the ambient temperature dips to below around 25 def F (-4 C) and lower, the carry side belting only partially conforms to the idler trough, empty and partially loaded. This makes empty belt tracking difficult as there is little to no contact on the idler center rolls. Loaded tracking is better. At lower temperatures (under 10 deg F (-12 C)) the problem is much worse.
The belts stay partially cupped (do not flatten out - actually more of a serpentine shape) on the return sides, also affecting tracking, and alignment going into the load zones. Issue applies to the full length of each conveyor.
The belts are: Steel Cord, ST1000, 857 PIW, 36" (915 mm) BW, 1/4" (6 mm) TC x 5/32" (4 mm) BC. Covers oil resistant, Cord diameter 0.142" (3.6 mm), (63) cords, 0.543" (13.8 mm) pitch.
Conveyor A: 3,400 ft (1,036 m) c/c, 177 ft (54 m) overall lift, enclosed full length, with multiple concave and convex curves, return side drive, standard GTU.
Conveyor B: 2,075 ft (632 m) c/c, 115 ft (35 m) overall lift, enclosed full length, mostly horizontal with single concave curve to head end, return side drive, standard GTU.
Both conveyors are operating with the GTU counterweights at approximately 72% of our calculated amount. No known issues with slippage at drive pulleys.
Conveyor A is operated several times a week, must be purged after a run.
Conveyor B is operated several times a day, not necessarily purged.
Material handled is DRI (Direct Reduced Iron), mostly 1" (25 mm) minus, 109 lb/c.f.
The conveyor were placed into operation around March 2017, so this past winter was the initial cold temperature exposure for the belts.
If anyone has any experience with this I would greatly appreciate hearing your thoughts.
Many Thanks, ■