The jaw crusher is a machine that operates under very harsh working conditions. Therefore, it is necessary to do a good job in the maintenance and management of the machine. Only in this way can the machine be operated normally and the productivity of the machine can be improved. The article describes the maintenance management of the jaw crusher, in order to communicate with the peers.
There are roughly three types of jaw crusher planned maintenance: minor repair, medium repair, and overhaul. Minor repairs and medium repairs are the main repair methods. Through minor repairs and intermediate repairs, the equipment is maintained to perform well during the two overhauls and to determine the work of the overhaul.
The two repair gaps proposed below are calculated on the basis of three shifts per day.
Main contents of minor repair: inspection and repair adjustment device, adjustment of discharge port clearance; replacement of worn liners, thrust plates; repair and replacement of transmission parts; cleaning of individual parts of crusher; replacement of lubricating oil, repair, and adjustment of lubrication system Wait.
The interval between minor repairs depends on the operation of the equipment, usually from half a month to once a month.
The main content of the repair: including all the work of minor repairs. In addition, the worn thrust plates, bushings, tie rods, and linings are replaced; inspection, turning, grinding, and casting of eccentric shaft bushings, connecting rod bushings, and moving bushings.
The interval between the two repairs depends on the wear of the main bearing bush, the connecting rod bearing bush and the moving bushing, which is usually once a year.
The main content of the overhaul: including all the work of the middle repair. In addition, the eccentric shaft and moving mandrel of the turning or turning crusher are replaced; the babbitt alloy is cast on the upper part of the connecting rod; the parts and components that are worn out are replaced and restored; the entire crusher is calibrated and the equipment is technically innovated.
At present, most of the repair of the crusher is a method of replacing the entire part, that is, the component pre-repair method. This method requires the beneficiation plant to have all the components of the crusher. When repairing, just remove the worn parts and replace them with new ones. In this way, the method of replacing the parts greatly shortens the parking time of the machine, thereby increasing the working rate of the crusher.
During the operation of jaw crusher, each part is subject to wear under the action of friction. The most wearable parts are movable lining, fixed lining, upper lining, lower lining, thrust plate and support. Pad (slider), rolling bearing or plain bearing, spring, etc. However, sometimes due to long-term wear or accidents leading to premature wear and damage, moving jaws, moving shafts, eccentric shafts, connecting rods, eccentric bearings, moving bearings, adjusting seats (supporting pedestals), rolling bearing seats, V-belts and Parts and components such as the flywheel and the body also need to be repaired to ensure their effectiveness. The factors affecting the premature wear and damage of the crusher parts are: the structure and working quality of the parts; the physical and mechanical properties of the broken ore; the ore crushing ratio; the material of the parts; the quality of the installation; the quality of use and maintenance and the timely maintenance.
Replacement and repair of major Jaw Crusher parts
Jaw crusher disassembly
The most frequent repair item for a jaw crusher is to replace the thrust plate. For the crusher with the connecting rod as the whole, to remove the thrust plate, firstly, the bolt of the baffle must be unscrewed, the dry oil lubricating oil pipe should be cut off, and the thrust plate should be hung on the crane lifting hook or other lifting device before releasing. The spring at one end of the horizontal rod pulls the movable jaw in the direction of the fixed jaw and takes out the thrust plate. If the rear thrust plate is to be removed, the connecting rod should be pulled apart from the front thrust plate and the moving jaw, and the rear thrust plate should be taken out.
Generally, the wire rope is used to pass through the opening on the foundation, and the manual winch for disassembling the thrust plate is used to pull the movable jaw or the movable jaw together with the connecting rod from the front wall of the crusher. Before pulling it open, the connecting rod should be placed at the bottom position. When the connecting rod is in this position, the discharge port is the largest. In order to disassemble the moving shovel, the dry oil lubricating oil pipe must be cut off, the tie rod should be disassembled, the bearing cap removed, and then the crane should be pulled out by a crane or other lifting equipment.
Repair of the jaw crusher main shaft
The boring journal of the compound pendulum jaw crusher should be repaired to the following extent: ellipticity >0.05 mm; conicality >0.04 mm; journal surface relief >0.04 mm.
The repair method for the journal is:
1) Under the condition that the strength is allowed, the worn journal will be nested after turning and the original fit size will be restored. The sleeve has a thickness of 4 to 6 mm and can be matched with D/gc.
2) Appropriate technical measures are taken to weld the worn journal to the “long meat”, and then turn the machining to restore the original fit size (this method is only applicable to the journal repair of the body part).
3) Repair the vibration and metal spray methods to restore the original fit size if conditions permit.
Repair of the eccentric shaft
The eccentric shaft of the simple pendulum jaw crusher should be repaired when the wear is as follows: ellipticity > 0.10 ~ 0.15 mm; conicality > 0.08 ~ 0.12 ram; journal surface convexity and concavity > 0.10 ~ 0.12 ram.
The repair method is:
1) According to the wear situation, lathe turning and scraping repair can be taken. After repairing, the journal is slightly smaller than the original fit size. At this time, the sliding bearing should be prepared.
2) Special circumstances, under the premise of strength permit (such as severely damaged journal) can be nested after the original journal turning, restore the original fit size, the thickness of the sleeve is 5 ~ 6 mm, D / gc can be used.
3) When conditions permit, repair by vibration welding or metal spraying can be used to restore the original fit size.
Sliding bearing repair of eccentric shaft
The repair of the bearing is primarily determined by the limits of the top clearance and geometry changes. When the bearing does not have severe local wear, and the top clearance increases, the cushioning method can be adopted to adjust the tip clearance, but when the wear exceeds the general limit (0.25% of the journal) and the local wear is severe and there is a large area. When it is broken (falling off), it must be repaired. The repair methods include: 1 local repair and turning of local defects, such as grinding, ellipse, large and small cracks, partial drop, the simplest method can be used for gas welding, manual scraping or mechanical processing, which is fast and easy, and the effect is basically It is reliable (it should use the original babbitt material to make up the meat). 2 All recast or layered gas welding “long meat”. Casting with a bearing thickness of 10 mm or more and a thickness of 10 mm or less, stratified gas welding “long meat” can be used. The thickness of the weld repair should be at least 4 mm and can then be machined.
Connecting rod repair
During the working process, cracks, breaks, bearing hole wear deviation, support pad groove wear or wear deviation, and connection screw tripping shall be repaired in time. Practice has proved that cracks occur in the lower part of the connecting rod and even break. In the event of a major accident, if the repair technical measures are taken properly, it can basically be resumed.
Cracks or breaks in connecting rods generally occur in the lower part. The specific repair methods often use direct welding and reinforcing steel plate welding. The direct welding method is simple and suitable for medium, small, short and shallow cracks. It is more troublesome to reinforce the steel plate, but the effect is reliable and suitable for large, long, deep cracks and breaks.