Maintenance of 10 major fault-prone parts of Jaw crusher Ⅱ

06 Elbow plate replacement

In the production process, because of the large stress, the elbow plate often has cracks or even cracks, and what’s more, there will be transverse faults, which need to be replaced in time. When replacing, first take out 2-3 pieces of steel plates as adjusting the size of the blanking port, push the movable jaw forward with the jack to prevent it from falling, hang the bottom of the movable jaw with a steel wire rope, and connect the upper part of the movable jaw with a 5-ton chain to the frame for stretching, and loosen the bolts of the adjusting rod. At this time, the steel drill can be used on both sides at the same time, and the waste elbow plate can be slowly lifted out with the help of the crane. After the new elbow plate is installed, the steel drill can be used everywhere.

07 Crack treatment of elbow plate seat

When the elbow plate was replaced, it was found that there was a crack in the channel steel of the elbow plate seat, which eventually led to the movement of the elbow plate in the seat, thus reducing the service life of the elbow plate. The elbow seat needs to be treated. The key point of this work is to take out the internal channel steel.


First of all, the scheme of taking out the channel steel by bolt fastening is adopted, that is, welding high-strength bolts at two ends and three places in the middle of the channel steel, cutting three steel plates with bolt holes in the middle, and tightening them with three wires at the same time, trying to take out the channel steel, but because the channel steel has been bitten by the elbow plate seat, this method has broken several bolts, bent the steel plate, and did not take out the channel steel.


After that, the oxygen acetylene is used to cut the cracks from the middle of the channel steel, and then the two ends of the channel steel are taken out respectively. Finally, the channel steel is taken out, embedded in the new channel steel and welded to the elbow plate seat, and then installed for use.

08 Jaw plate reversing and replacement

After a period of normal wear and tear of the jaw plate, the rack on its face will be blunt or completely flat, so it is necessary to reverse the upper and lower jaw plates for multiple use. After the second grinding, the jaw plate needs to be replaced.
First of all, the bolts of wedge, guard plate and slide plate need to be removed and lifted out successively, and then the welding lug on the upper part of jaw plate should be lifted out. If it is reversed, the lug should be cut off, and then the welding lug on the opposite side should be installed at the lowest part (if it is not needed to replace it). The second jaw plate is also installed backward. For the installation of jaw plate of jaw crusher, it needs to be firmly attached with jaw bed. Soft metal is used as gasket to ensure that it can be used after being leveled and then tightened with bolts. In the working process of the crusher, regularly check whether the jaw plate is loose. If it is loose, even adjust it to prevent breaking or wearing, so as to reduce the service life of the jaw plate.

09 Treatment of oversized material

Because the raw material is mountain blasting stone, and it is loaded by Komatsu pc360 excavator and transported by Steyr dump truck, it is inevitable that the oversized material will affect the production efficiency of the coarse crusher. After the oversized stone enters the feed port of the coarse crusher, it will block the feed port and affect the normal operation. The treatment is labor-consuming and time-consuming, and it is not safe. This system has had safety accidents due to the treatment of oversized material. Therefore, the oversized material in the raw material must be treated before entering the feeding port of the coarse crusher of the sand making production line.


In order to deal with oversized materials, we adopt the pre screening method of lattice screen, blasting method, crushing method of crushing hammer, and lifting method of derrick. The pre screening method of grid screen uses 43kg / m rail to make grid screen with 400 mesh × 400mm。 In the process of using, the rail is impacted by the stone continuously, the deformation is large, and the oversized material is not easy to transport away. It is also time-consuming and affects the normal feeding of the coarse crusher; The blasting method and the crushing hammer method can only deal with the over diameter stones on the surface of the pile. However, the over diameter stones inside the pile can not be treated, which can not solve the problem fundamentally; The lifting method of derrick (crane) is to set up derrick (or crane) at the side of each coarse crusher bin and lift it with single drum hoist (or crane) with lifting capacity of no less than 5 tons. The oversized stones that have entered the bin are tied up with steel wire rope and lifted out. The blasting is released in a centralized way, and then the materials are sent to the bin by loader.

10 Handling feeder pulley sliding key

Due to long-term operation, the connecting spline between the belt pulley and shaft of the feeder appears sliding key phenomenon. We use roller extrusion or overlaying welding to re process to the basic size. Manual arc welding is generally not recommended because it has great influence on the material of the parts. Or the keyway is reduced by electric welding and polished by angle grinder, or the keyway of belt pulley is processed by new spline fit. The surfacing layer is uniform and compact, without block dropping, delamination, slag addition, crack and burning loss; If the fit clearance between spline tooth and sleeve is less than 3% ~ 4% of tooth width, it is not allowed to repair, and the service limit is 10%. For the small value of fixed combination, the positive and negative can be larger. At the same time, external bolts are used to fasten the steel plate during the installation process to prevent the spline and belt pulley from shaking.

If you have a problem with jaw crusher, Fodamon engineer will answer it and help you solve the problem.

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