One of our clients has experienced a conveyor belt cupping issue during cold temperature operation. Here is a description of the issue:
On two (2) 36” (915 mm) BW conveyors when the ambient temperature dips to below around 25 deg F (-4 C) and lower, the carry side belting only partially conforms to the idler trough, empty and partially loaded. This makes empty tracking difficult as there is little to no contact on the idler center rolls. Loaded tracking is better. At lower temperatures (under 10 degrees 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 side, also affecting tracking, and alignment going into the load zones. Issue applies to the full length of each conveyor.
Conveyor Belt Cupping
One of our clients has experienced a conveyor belt cupping issue during cold temperature operation. Here is a description of the issue:
On two (2) 36” (915 mm) BW conveyors when the ambient temperature dips to below around 25 deg F (-4 C) and lower, the carry side belting only partially conforms to the idler trough, empty and partially loaded. This makes empty tracking difficult as there is little to no contact on the idler center rolls. Loaded tracking is better. At lower temperatures (under 10 degrees 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 side, 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 Dia 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, 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, 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 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 conveyors 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 insights.
Many Thanks, ■