Analysis on the reason of steel bar breaking in rod mill
Date：2019-07-15 11:41 Source：未知Views:
There are many reasons why the bar (wear-resistant steel bar) of the bar mill breaks. Today I simply list the following points for your reference:
1, bar mill steel bar (wear-resistant steel bar) less or more feed
The amount of rod mill steel rod (wear-resistant steel rod) is related to the height of rod mill steel rod (wear-resistant steel rod) being lifted and the impact times, impact force size and effective grinding area of the broken rock, which has a great impact on the production efficiency of the rod mill.The experimental results show that the filling rate of the bar mill (wear-resistant steel bar) is better at 40 ~ 45.But most domestic projects are below this range, a few are only about 30.Due to too little rod loading, the proportion of the throwing and dropping of the rod mill steel rod (wear-resistant steel rod) is also reduced correspondingly, and the production efficiency is reduced. The stones entering the mill cannot be broken to a finer degree in time and are rushed out of the mill by water, which can only be broken into coarse particles sandwiched in the rod seam and waiting for further crushing.In this way, the joints of the rods are often filled with stone debris, thus losing the constraint effect on the upper grinding rods, causing changes in the arrangement of the grinding rods.Too much feed, also easy to cause "indigestion" and cause the same results.
2, rod mill at both ends feed or add water is not equal
The bar mill used to make sand is generally end feed, end add water and the middle edge of the discharge.Obviously, the feed at both ends of the mill is not equal, easy to make the rod mill steel bar (wear-resistant steel bar) askew.When the axis of the feeding belt is vertically arranged with the grinding shaft, the deviation of the belt will lead to unequal feeding at both ends.When the two parallel layout, because of the stone movement inertia, it is more difficult to ensure the uniform feeding at both ends.If the feeder, which is shaken by the rocker arm, is used to feed the material to both ends of the mill alternately, the feeding at both ends will be artificially unequal, which can not only avoid the breaking of the rod, but also increase the chance of the skewness and fracture of the rod mill steel rod (wear-resisting steel rod).
If the water added at both ends is not equal, the discharge is not equal, the result is equal to the feed is not equal.special Is when grinding pebbles, because the pebble grains round surface light, easy to roll and bounce, add more water, one end of the pebble will be washed by water from the grinding end, or even directly discharged by the discharge port, resulting in one end of the material more, less material, making the rod mill steel bar (wear-resistant steel bar) aslant.
3. The feed grain size of bar mill steel bar (wear-resistant steel bar) is too large
The maximum particle size of continuous material depends on the size of rod diameter. A spherical pebble with a diameter of 25ram can fill the gap between two grinding rods of 100.If the stones size larger, and its 靭 sex is very good, will be difficult to break.They are blocked in rod joints and will cause the rod mill steel (wear-resistant steel) above them to lose the constraint of rod joints.Although the size of the feed is strictly controlled by sifting, the overdiameter phenomenon is always inevitable.As long as there is an overdiameter, the grinding rod may be askew.Using medium stone (maximum particle size of 40ram) to make sand, not to mention.
4, unqualified bar mill steel bar (wear-resistant steel bar) elimination is not timely
Rod mill steel rod (wear-resisting steel rod) wear to a certain extent, it is easy to bend and fracture bending rod and broken rod if not removed in time, will further cause other rod arrangement disorder.But the operator can not see the rod mill steel rod (wear - resistant steel rod).Fixed this, can not be found in time bending rod and broken, can only be regularly opened book mill inspection.Such checks are often an afterthought.At the same time, because the inside of the rod many, empty ask small, plus the rod mill steel rod (wear-resisting steel rod) bulky, want to completely clear has bent and broken, and will bend and fracture blind rod, is also very difficult.As a result, it often leaves some hidden dangers.
5, the rod mill internal parts fall off
Rod mill barrel is equipped with lining plate.The liner is fastened to the drum wall by bolts.Under the great impact of the grinding rod, the fastening bolt is easy to loosen and even be cut off, resulting in bolt and village Board fall off.Linings are large and not easily broken, and it is not difficult to imagine what will happen when they fall off.
During the operation of the rod mill, the parallel arrangement order of the rod mill steel (wear-resisting steel bar) is disturbed, which causes the rod mill steel (wear-resisting steel bar) to collide with each other, leading to the deterioration of the stress condition of the rod, which is one of the fundamental factors leading to the fracture of the rod.