Self-lubricating bearings have a wide range of operating temperatures, adequate solid lubricant content, uniform release, good self-lubricating properties, and good seizure resistance, which can effectively protect journals and achieve long-term use. Suitable for operation in high temperature, low speed, heavy load, large dust, water shower and shock and vibration environment. It can be widely used in the rolling of mechanical equipment such as mining machinery, metallurgy, petroleum, chemical industry, food, textile, papermaking, printing and dyeing. And sliding bearing parts.
The aluminum ingot produced from the aluminum reduction cell is poured into the mixing furnace after being sucked and sucked by a vacuum. After passing through the proportioning and deslagging, the aluminum ingot is poured into an aluminum ingot casting machine to be cast and molded. The formed solid is called an aluminum ingot and the aluminum is produced. Ingots are stacked by a stacker. In order to increase the production efficiency, aluminum ingots must be cooled with a large amount of cooling water before they are formed. During the cooling process, the huge thermal energy of the aluminum liquid is released into the cooling water to generate hot steam. Casting machine bearing is in the high temperature and steam environment, many bearings are grease lubrication, the added grease will be removed due to melting and overflow in a short time due to high temperature, maintenance and maintenance is difficult, the equipment surface is also easy to test. In addition, steel bearings are susceptible to corrosion and rust in hot and humid environments. The failure rate is very high and equipment maintenance costs are high. Equipment operations are often plagued by the following two problems.
It is difficult to achieve high-temperature continuous operation of the oil supply operation. The casting machine's devices such as pulling ingots, transfer bars, splices, and ingots are all installed in the unit housing, and each time the engine is shut down, the housing is removed and grease is applied with the oil gun. And as many as 30 injection points of the whole machine, long-term operation and maintenance can not achieve this cumbersome oil injection operation, had to carry the thin oil bottle pouring in the running outside the bearing sleeve, the lubricant is difficult to enter the friction between the bearing, large Some bearings are in friction.
High ambient temperature, grease lubrication is not suitable for the current molybdenum disulfide grease used in the casting machine rolling bearings are considered to be resistant to high temperature grease, we know that its base oil is a petroleum product, plus a small amount of high temperature resistant molybdenum disulfide additive, its temperature limit That is 1200C. It is measured that the working temperature of the caster bearing can reach 2000C, which is far more than the grease will be thinned and gradually evaporated. The remaining carbon slag, molybdenum disulfide, and dust are mixed into a solid block solidified on the cage of the rolling bearing, not only Loss of its lubrication, but also hinder the normal operation of the rolling bearings and wear quickly, more than 2 weeks have to stop, remove the bearing cleaning and replacement of oil.
First, the wear condition
The abnormal wear of the bearings caused by two major problems in the operation of aluminum ingot casting equipment bearings is more serious. Taking an enterprise's pulling spindle mechanism as an example, the average service life of the bearing is 2 months. When the wear is serious, the 5mm inner ring is worn out, causing the equipment to continue to operate. The reason is that the original design to oil can not be realized, had to be outside the bearing in the process of burning thin oil, a small amount can be leached into the bearing, the wear is small, and more than 50% of the shaft and sleeve are not lubricated, in the soil friction The state produces strong adhesive wear. This wear quickly increases the clearance between the shaft and the sleeve, so that the dust can easily enter and cause a vicious cycle.
Second, the choice of oil-free self-lubricating bearings
In order to solve the problem of high temperature, low speed, heavy load, large dust, water shower, and impact and vibration in the mechanical equipment, the oil-free self-lubricating bearing is selected.
1. Bearing construction
The self-lubricating bearing is developed on the metal friction surface of the bearing base with an ordered and sized hole, and is embedded with molybdenum disulfide, graphite, etc. The composite self-lubricating block is embedded in the metal sleeve and the composite slider can be made in the 2800C. The normal working temperature. However, due to its low mechanical strength, weak carrying capacity, and easy deformation, it can inhibit this shortcoming by inserting it in a metal hole, forming a metal part to bear the load, and a self-lubricating block to act as a lubricant. The lubrication mechanism of this self-lubricating bearing is that during the oil friction between the shaft and the sleeve, a part of the self-lubricating material molecules is transferred to the metal surface of the shaft, fills the small non-planar surface, and forms a relatively stable solid lubricant film. Causes the body to grind against the wear and prevents the shaft from sticking to the sleeve. This combination of plausibility combines the complementary advantages of copper alloys and non-metallic wear-reducing materials, and is particularly suitable for the movement of oil-free, high-temperature, high-load, low-speed, anti-fouling, anti-corrosion, and strong radiation environments. It can be used under special working conditions where it is wetted with water or other solutions and no lubricating grease can be added at all.
2. area
The self-lubricating block accounts for the ratio of the surface area occupied by the self-lubricating block and the operating speed and bearing strength, and the running speed is low. The bearing pressure strength is large, and the area occupied by the metal should be larger. For example, the area occupied by the lubricating block of the roller bearing of the grab wheel trolley is about 25%, and the lubrication of the pull spindle mechanism should be sufficient. The bearing strength is not great, and the area occupied by the self-lubricating block is about 65%.
3. Technical requirements for bushing materials
Bushings should be made of alloyed copper. The bushings must have high hardness and generally must be heat treated. Their hardness is not lower than HRC45.
4. Self-lubricating block geometry and mounting requirements
The shape of the self-lubricating block is cylindrical and rectangular. Self-lubricating can use columnar shape according to the occupied area, and vice versa. No matter what shape it must be inlaid firmly to prevent it from falling off during operation.
5. Bushing and shaft clearance clearance
Bushing and shaft fit clearance value The coefficient of linear expansion of the self-lubricating block is 10 times that of steel. In order to adapt to bearing temperature changes, the gap between the shaft and the bushing is adjusted from 0.032 to 0.15mm (D4/dc4) to 0.45~0.5mm. The self-lubricating block protrudes the bushing metal by 0.2~0.4mm on one side of the friction pair. This will be fully lubricated during the initial running-in period of the bearing operation, reducing the power consumption of power driving.
6. The advantages of oil-free self-lubricating bearings
a. No oil lubrication or less oil, suitable for places that can not be refueled or difficult to refuel, can be used without maintenance or less maintenance.
b. Good wear resistance, low friction coefficient and long service life.
c. With proper amount of elastoplasticity, the stress can be distributed over a wide contact surface and bearing capacity can be improved.
d. The static and dynamic friction coefficient is similar, which can eliminate the crawling at low speed, thus ensuring the working accuracy of the machine.
e. It can make machinery reduce vibration, reduce noise, prevent pollution, and improve working conditions.
f. The transfer film can be formed during operation to protect the grinding axis without biting axis.
g. For the low hardness requirement of the grinding shaft, the unconditioned shaft can be used, which reduces the processing difficulty of the relevant parts.
h. Thin-walled structure, light weight, can reduce the mechanical volume.
i. The bushing is made of brass and can be used in corrosive media.
Through the practice of an aluminum company, the caster bearing was changed to an oil-free self-lubricating bearing, which has been used continuously for 15 months and is still running. The clearance between the shaft and the bush is generally not more than 1mm, and it is expected that it can be used for another 12 months. More than the original service life (2 months). Oil-free self-lubricating bearings can be used not only in aluminum ingot casting machines, but also in oil-free, high-temperature, high-load, low-speed, anti-fouling, anti-corrosion, and high-radiation environments, as well as in water. Or other solution infiltration and can not add lubricating grease at all conditions under the conditions of the equipment, this type of bearing is worth our electrolytic aluminum companies to consider.
Linear Light
Simple but timeless, LEDER technology`s linear light delivers enough illumination and embodies the beautifully understated elements of minimalist design with clean lines and modern features.The clean lines of the linear light remind of early modern style.
This linear light is a stunning contemporary statement light fixture for your home. This versatile linear light is the perfect pick to add a touch of contemporary-style wherever you install it. The linear light`s stylish design blends into almost any decor in the bathroom, dressing table, mirror cabinet, bathroom vanity, and so on.
Features:
• Minimalist design
• Easy Reliable Installation
• Contemporary style
• Energy saving save electricity
• Color temperature :3000k-6000K
• Body color can be customized as RAL Code
• Type of protection: IP20
• Warranty:3 - 5 years
Versatile enough for almost any interior where the dramatic statement is needed such as a foyer, dining room, living room, or bedroom.We have rich production experience in lighting.Except LED Linear Light, we also offered other product in Indoor Lighting .Such as : LED Downlight , LED Panel Light, Track Light ,Wall Light , LED Strip Light , LED Tube Light , Cabinet Light , LED Bulb , LED Ceiling Light as so on .