Re: Joints Opening At Edges
Hi,
The reason this is happening could be many fold. Firstly, if it is a new installation then you need to check the system design as the problem may well be excessive edge tension or an inadequate specification of the conveyor belt. If it is a splicing technique issue then as most tension is on the belt edges with a steep angle conveyor, the logical failure point is the edges. Any input from our part is guessing without a lot more information.
Cheers
Col Benjamin
Gulf Conveyor Systems P/L
www.conveyorsystemstechnology.com ■
Steep Angle Belt Splice Failures
Please provide the conveyor geomtry and operating specifications that can be readily checked for overstressing.
What did the designer say about the dilemma and about a prudent repair?
We may help with reasonable input. By "S" do you mean a Snake Conveyor? ■
Re: Joints Opening At Edges
Thanks a lot in your participation.
After the recent changes in our portal layout , I am not receiving the regular updates.
Hence excuse me for my delay in response.
I will post the general arrangement drawing at the earliest.
Thanks & regards, ■
Re: Joints Opening At Edges
Dear experts,
Please find the attachment showing our conveyor profile. Item 11 shows the top deflection wheel at which the conveyor takes 90 degree turn from horizontal to vertical turn. The deflection wheel takes the vertical pulling load when the belt passes the pulley. Only the area outside the side wall is touching the pulley's face width.
How is the relation between the rating of the belt and the face width of this deflection wheel? Can there be any basic guide line?
Thanks to all & kind regards,
Attachments
■
Waiting
Dear Experts,
I think that many of the experts have not seen my above post. Hence I am repeating.
Please bear with me if you had gone through this.
I will be thankful that if someone clears my query.
Thanks a lot & High regards, ■
S Shaped Conveyor
Mr. Ganesh,
Did you ever get a response for your issue?
You can email me at aduncan@dossantosintl.com.
Amy Duncan
Dos Santos International ■
Conveyor
Please find the attachment showing our conveyor profile. Item 11 shows the top deflection wheel at which the conveyor takes 90 degree turn from horizontal to vertical turn. The deflection wheel takes the vertical pulling load when the belt passes the pulley. Only the area outside the side wall is touching the pulley's face width.
How is the relation between the rating of the belt and the face width of this deflection wheel? Can there be any basic guide line?
Thanks to all & kind regards,
It all depends on the wrap angle the conveyor belting can tolerate. The thickness of the belts carcass in construction plus the quality of the top and bottom rubber is the key to allow the maximum wrap angle. The maximum wrap angle relates to it flexibility in use to go over and under drive or driven pulleys. ■
Better Never Than Late.
Back in the '80's I was told by Flexowell that the carcass does not extend as near to the edges as it does with flat belts. It was something to do with cooling around the larger heat sink around the sidewall joint. It is likely that the OEM was finished with autoclave-like thoroughness.
I would be surprised if anybody could perform totaly effective splicing on the installation shown without prohibitive downtime to the adjacent furnace.
While some Suppliers will do anything for a sale a reasonably diligent Owner should have seen this one coming from day two. ■
Joints Opening At Edges
Mr. Ganesh,
Looking at your drawing I am surprised that your edge only contact deflection wheels appear to be the same diameter as the full contact pulleys. This may result in excessive local pressure which produces kneading of the fabric plies which is fatigue and causes ply separation. Check with your supplier and the belt manufacture to determine the appropriate diameters for both the full contact pulleys and the edge onle contacting deflection wheels. I strongly suspect that your problem is in the diameter of the deflection wheels.
My first reaction is to think that the top deflection wheels are the source of your problem as the tension is higher there than at the lower deflection wheels thus the kneading pressures are higher. On the other hand, at the lower deflection wheels where the tension is lower the inner fabric plies may actually be subject to compression and this maybe even more detrimental.
If splicing alone was your problem I would recommend increasing the bias angle to 45 degrees but I suspect that your problem is deeper than just the adequacy of your splice.
Joe Dos Santos ■
Rectangular Or Biased Joint ?
Thanks a lot Mr.Joseph A. Dos Santos.
For steep angle conveyors , we are following rectangular joints and for all other locations ( troughing conveyors, dosing conveyors, weigh feeders etc., ), we are following biased joints. I tried to get the reason in my earlier threads. But I could not get the answers.
Regards, ■
Joints Opening at Edges
Dear Experts,
We have a steep angle conveyor, having EP 1000/6 of 1200 mm width & 02 fabric breaker plies ( one at top & one at bottom ). It is "S" shape configuration. We are facing the side edges opening at the hot vulcanized joints.
After one month of hot vulcanizing, one side edge is showing the indication that gap is developing between top & bottom ends at the joint and it is slowly progressing both length wise & width wise.
After sometime opposite edge is also starts opening. We are trying to repair by cold patching and by mechanical fasteners. But the progressive of opening of the joints could not be stopped which compels us to go for a new joint. Each hot vulcanizing joint gives only one month life.
Every time before hot vulcanizing we check the machine. Joint is done by many vulcanizers.
We are using edge bars also. Head end deflection wheel was found slightly worn out. It was replaced.
Joint step length was increased from 200 mm to 250 mm for additional safety. But still problem is not solved.
Seeking your advice please.
Thanks & regards, ■