Bearing bridge in rod mill
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Between dry grinding and wet grinding of the steel rods in a rod mill, which method tends to cause bridging more easily? How should it be maintained if a bridge is built?
Is the poster asking about bridge construction using steel bars, or bridges built with coal? Please clarify
It should be a bridge built with steel bars, commonly referred to as a “mess of bars”. In my opinion, the random movement of the steel rod is caused by broken rods, and broken rods resulting from low loads are the main reason for such random movement.
Bridge formation usually occurs when there are too many new rods or short rods; the common solution is to pick out the short rods and use a crowbar to straighten the steel rods.
I’ve been working with rod mills for over a decade and have never seen chaotic rod behavior
Hehe, our mills here have also had problems with broken rods; those breaks were caused by broken rods as well.
1. When comparing dry grinding to wet grinding for the steel rods in a rod mill, the probability of misaligned rods remains the same. It is mainly affected by factors such as operating procedures, parameter specifications, coal type, and the level of manual operation on site. 2. Broken rods occur due to fractured rods; 3. Fractured rods are caused by issues with the quality of the rods themselves as well as problems in the manufacturing process on site (mainly large fluctuations in load). 4. After a broken rod occurs, the machine must be stopped to remove the broken part and realign the steel rod. 5. Drive on to continue production.
This situation rarely occurs during normal operation; I haven’t encountered it yet. Just don’t operate at low load for long periods of time
Let me talk about our actual situation. After stopping the mill, we drained the slurry, and it remained shut down for several days. During that time, we followed the proper procedures for rotating the mill. But a few days later, we found that some of the steel rods had protruded from the mill and were resting at the discharge outlet; the situation became more chaotic as the mill was rotated. After removing all the steel rods, we discovered that some of them had been completely broken. In other words, bridging occurs only after the drum is rotated.
My doubts are as follows: 1. The size of the steel rod is too short inside the grinder, resulting in large gaps at both ends. 2. Although the coal slurry was discharged, the mill was not rinsed; a few days later the slurry dried up, resulting in uneven frictional resistance from the steel rods inside the mill. 3. Too many steel rods are installed.
I agree with your view. Long-term low load is one of the reasons for rod breakage ； The coal mill liner is one of the reasons for rod breakage ； The third issue is the quality of the grinding rod. The rubber-lined plates previously used in our factory had a high hump, causing most of the grinding rods to be flung upward, which resulted in a large number of broken rods. Now, with the use of steel linings, broken rods are very rare; hardly any are found during overhaul inspections.