Hi all
there can not any dispute in basic. The roller can not touch the dam ring during operation. Only in case of any break down( tie rod failure), it may touch. But by that time, the mill will be tripped either by the proxmity switches or vibration.
Normally, the dam is used to get damaged by foreign material from rawmaterial or the mill roller itself may break due to fatigue and the samll piese may struck in between roller and dam ring.
Coming back to the original question,
when the dam ring height is very less, it will lead to mill vibration.when it too high, it lead to high mill power, lesser drying rate and too high bed.
hence, it sholud be balncd between the vibration and mill KW.After a period of operation it is normal to have the wear on the table liner and hence the mill KW will go up. So we should periodically reduce the dam ring height( around 5 to10 mm for 2 months) to maintiin the same bed height.
If the dam ring is damaged, it is better to replace the dam ring so that there will be uniform bed and hence output will be improved and vibration will be lesser.
Hey to All;
The roller can move from its original position (few centimeters) and can touch the dam ring, several times I have seen this fenomena in our 200 tph vertical mill, alot of time we have opened the mill door (after tripping due to vibration) and found one roller not in postion and in touch postion with the dam ring. adusting the roller position can be done be removing part of the material under the roller ( if excess material) and then start the auxilary motor for few minutes (experienced alot of times).
Regards
Dear Mr.Nael,
Could you please tell who are the original supplier of your VRM? We never experienced such problem in Loesche & Atox mill.