Dear Mr. mpsingh,

It is not advisable to merge both the unit at 35 mtr by removing the wire ropes from safety point of view.

Check the effectiveness of the V-Plough scrapper placed before the take-up bend pulley, as the fines sticking to the return belt also cause belt offset problems.

Regards,

Shakee ■

In addition to other recommendations above.

You also need to check the bend pulleys going into and out of the take-up. They need to be completely square to each other axially and square to the structural frame of the conveyor for proper tracking of the belt through the take-up zone.

Ensure that the counterweight is not built up unevenly with loose material, ensure that all 4 cables are of equal length and the weight is distributed evenly among all 4 cables. Ensure that the counter weight is evenly distributed in the CW frame.

Moving the CW to the pulley frame will not help if the problem is somewhere else. ■

How runs the tripper car? ■

Dear Mr. Singh,

Kindly check the clearance between the guide of the take up frame and the take up. This should be minimum as the increase in this gap will further create unbalance of the frame further leading to the belt sway problem.

It is not recommended to move the counter weight near the take up pulley as the above conveyor will have quite a large take up weight and belt snapping can lead to major accidents. As said in one of the above reply check that the counter weights are uniformly distributed with the minimum gap between the take up frame and it guide. ■

Originally Posted by mpsingh

dear all,

we have vertical gravity takeup unit in tripper conveyor 470 mtr C/C length. Its takeup consistes of two units. 1) Takeup pulley at 35 mtr elevation and 2) Counter weight at 9 mtr elevation.

both are connected by four wire ropes at four corners of both frames.

we experience problem of unbalancing and belt offset problem at takeup pulley.

is it advisable to merge both the unit at 35 mtr by removing the wire ropes.?????

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Are you stating that your surge pile belt flight is 470 Meters with a total

flight length of over 558 Meters using 1,116 meters of belting??????????????????????!!!!!!!!!!!!!!

Has any maintenance been done on the belt recently like a new splice?

This issue may be in direct response to the maintenance performed

Adding to what my friend Gary has said:

About your tripper belt;

Is the gravity take up not close to the drive unit and close to the drive unit on one end of the surge pile/bin?????????

Are all the pulleys flat without lagging?

Is there V plow on the end of the tripper belt? Is the tail pulley a beater pulley?

IN our case the gravity take up was suspended by the belting on a vertical sled in both the old screening plant and the surge pile on the 1928 level.

Just so I understand this completely your gravity take up and pulley are not on the same sled on the first tower with the set of rails with weight basket or plate steel weights bolted to the take up pulley sled?????????????????? Please expand on why this was done if you would.

Does one side of the belt have worn edges or webbing exposed? was this done to act as a safe hold device for the counterweights bounce at start up-normally the counterwieght sled does not have a set of 4 wire ropes (only the take up pulley and the weight sled underneath it)

(at least this was what was done in our surge pile and still works)

The first things that come to mind are:

1. The surge pile/bin belt is stretched and may need a section cut out of it-which is the quick fix when you find the bad section which can be clamped off on the tripper frame side and replaced witha shorter section of new belt.

a. belt is old and stretched anyway and may be bad entirely and ready for replacement.

b. bad splices.

c. dust build up on rails affecting the linear trajectory and traction of the entire tripper sled may act like it is trying to jump off the rails of the tripper frame).

d. frozen steel wheels on the tripper trolley

d1.frozen steel wheels on vertical take up if used.

e. stretched wire rope on the vertical weight take up-this does happen with wire rope and the rule is replace the wire rope when there are six

broken strands at any location.

f. wire rope(s) are not/or have not been lubricated at any time.

f1.the wire rope for the tripper trolley is stretched affecting the linear path of the tripper belt and affecting the linear path of the tripper belt.

g. steel wheels if used on tripper trolley are not or have not been greased which will cause binding and slipping.

h. frozen return idlers.

i. frozen troughing idlers.

As Gary has so kindly mentioned the geometry of the structures pulleys could be the issue entirely but the problem must be examined completely by also running survey string to assure the tripper belts centerline is still intact as a simple tilting of one degree or less of the foundation(s) at any point can and will be the crocodile under the water at the rivers edge.

As louis has also said how runs the tripper car? Our tripper car was and does misbehave simply because of dust build up on the angle iron welded to the structures rails used to create a trolley track for the tripper car.

The other issue is training idlers if there is no training troughing idler just below the head pulley on the tripper car or a set of return idler training idlers every ten idlers you may have problems with training the belt.

You might be lucky in only needing a compressed air line with a long wand to wash all the dust off. ■

For proper operation all pulleys must be level and square to the belt line. In the case of the moving take-up pulley its movement mus be guided in a frame that is kept square to the belt line as it moves. Beyond that it is a matter of training the empty belt in a conventional manner, with the idlers and by loading the material centrally. The remote location of the counterweight is likely for safety reasons. It is important that cable lengths are equal and don't contribute to skewing of the take-up pulley.

Joe dso Santos ■

Originally Posted by mpsingh

dear all,

we have vertical gravity takeup unit in tripper conveyor 470 mtr C/C length. Its takeup consistes of two units. 1) Takeup pulley at 35 mtr elevation and 2) Counter weight at 9 mtr elevation.

both are connected by four wire ropes at four corners of both frames.

we experience problem of unbalancing and belt offset problem at takeup pulley.

is it advisable to merge both the unit at 35 mtr by removing the wire ropes.?????

Dear Mr.M.P.Singh,

Would it be necessary to have four ropes ? Could it be changed by one higher diameter rope ? I had faced similar problem. I changed four ropes to one rope.

Atleast I could eliminate the doubt of nonuniform tension among four ropes.

I do not prefer joining counterweight with take up pulley as others have also expressed the same concern.

Regards, ■