"Bearings are damaged in many ways. Today we will talk about them in detail. The first one is peeling, which is mainly peeling off the running surface. After peeling off, it will show obvious convex and concave shapes.
What are the reasons? First, excessive load and improper use; second, poor installation; third, poor accuracy of the shaft or bearing box; too small clearance; intrusion of foreign matter; occurrence of rust; and decrease in hardness caused by abnormally high temperatures.
How to deal with it? Re-study the usage conditions, re-select the bearing, re-consider the clearance, check the machining accuracy of the shaft and bearing box, study the design around the bearing, check the installation method, check the lubricant and lubrication method
The second is bearing burn, that is, the bearing heats up and changes color, and then burns and cannot rotate. The reason is that the clearance is too small, insufficient lubrication or improper lubricant, the load is too large, and the rollers are deflected.
How to deal with it? Set the appropriate clearance; check the type of lubricant to ensure the injection amount; check the use conditions; prevent positioning errors; check the design around the bearing, including bearing heating; improve the bearing assembly method
The third is crack defects, which are reflected in some gaps and cracks. The main reasons are excessive impact load, excessive interference, large peeling, friction cracks, poor installation side accuracy, and poor use.
Protective measures include checking usage conditions, setting appropriate interference and checking materials, improving installation and usage methods, preventing friction cracks, and checking the design around the bearing.
Fourth, the cage is damaged, that is, the rivets are loose or broken, and the cage is broken. The main reasons are excessive moment load, high-speed rotation or frequent speed changes, poor lubrication, stuck foreign objects, large vibration, poor installation, that is, installation in an inclined state.
Abnormal temperature rise.
If it is avoided, take measures to check whether the use conditions do not comply with the regulations, check the lubrication conditions and whether there is oil leakage, re-study the selection of the cage, pay attention to the use of bearings, and study the rigidity of the shaft and bearing box.
The fifth is scratches and strains, which are rough surfaces with slight dissolution; scratches on the ring ribs and roller end faces are called jams.
The reasons are poor lubrication, foreign matter intrusion, roller deflection caused by bearing tilt, oil breakage on the rib surface caused by large axial load, large surface roughness, and large rolling element sliding.
The measures are to further study lubricants and lubrication methods, check usage conditions, set appropriate preload, strengthen sealing performance, and use bearings normally.
The sixth is rust corrosion, which is reflected in partial or complete rust on the surface, and rust in the shape of rolling element pitch.
The reasons are poor storage conditions, improper packaging, insufficient rust inhibitors, intrusion of moisture, acid solutions, etc., and holding the bearing directly by hand
The measures are to prevent rust during storage, strengthen sealing performance, check lubricating oil regularly, and pay attention to the use of bearings.
There is also turbidity, which is the production of red rust-colored wear particles on the mating surface...
Wear refers to surface wear, resulting in dimensional changes, often accompanied by abrasions and wear marks.
Electric corrosion is a crater-like pit on the rolling surface, which develops into a corrugated plate shape.
The reason is that the rolling surface is energized, and the measure is to make a current bypass valve; take insulation measures to prevent current from passing through the inside of the bearing.
Indentation and bruises are surface pits caused by solid foreign objects stuck or impacts and scratches caused by installation..."
Liu Lang's understanding and understanding of machinery are much better than others, and his memory is extraordinary. No matter how many books he has read, he can never forget them as long as he wants to memorize them. Even if he does not memorize them at the time, he can still enter the memory in his mind if needed.
In a mysterious state, all the historical moments he has experienced can appear before his eyes.
In less than a month, Liu Lang had "armed" the workers' minds in theory, and the rest was to practice, practice, and practice again and again.
C's cutting tools were also shipped to Fucheng. The workers made the cutting tools in the morning and practiced making bearings in the afternoon. Everything was done step by step. At this rate, the first batch of 20,000 cutting tools will be put on the market in another month. There will be five in total.
Types, the most expensive one costs 56 yuan, and the cheaper one costs 37 yuan, which is two-thirds cheaper than imported knives. The quality is a little worse, but not much. The main problem is the raw materials.
For example, there are some problems in the heat treatment and cold treatment process.
Even though the quality is a little worse than foreign products, it basically meets Liu Lang's standards and has a very good price/performance ratio. Liu Lang believes that these knives will sell well after entering the market, and even supply will exceed demand.
The manufacturing of bearings is naturally slower, and the production of cutting tools has entered the schedule. With the arrival of cutting tools from West German Company C, the whole factory employees have set off a wave of work enthusiasm.
Every time Song Lifeng came to NORINCO Group, he saw that the factory workers were very motivated. These workers always gave people a "hungry" state. Such a scene could not be seen in other companies, which made him even more eager to carry out his tasks.
reform plan.
At the end of March, it was still a bit cold in Fucheng, but the spring breeze of reform could not stop. This year is the beginning of the 1990s and the first year of the country's Eighth Five-Year Plan. The whole country is full of energy.
Liu Lang reads the newspaper every day. From the national to the local level, the development direction of the new decade has been published. Vigorously strengthening domestic and foreign investment, increasing people's income, modernizing industrial transformation, technological innovation, strengthening education, etc. are all hot topics at the moment.
, frequently seen in newspapers.
At the same time, some words began to be slowly forgotten, such as the word self-reliance, which no longer appeared often in newspapers.
After all, now that the country has opened its doors, a large number of foreign companies have poured in, and self-reliance seems outdated. Besides, everyone realizes that it is impossible to catch up with Western developed countries just by working behind closed doors. Only by fully opening up to introduce technology, and then gradually digesting it into
I think this is the shortcut to development.
Of course, the fastest growing provinces are the southern provinces. They have taken advantage of their superior geographical conditions to stand at the forefront of reform. What blows to them is not the spring breeze of reform, but the violent wind of reform.
Standing in the strong wind, even a pig can be blown up into the sky. Liu Lang saw in the newspaper that the experience indicators of the southern provinces were constantly improving, especially Guangdong Province. In the early days of reform and development ten years ago, their total value
It is only half the size of Northern Liaoning Province, but two years ago, Guangdong Province was already on an equal footing with Northern Liaoning Province.
, As for the values ​​calculated this year, Guangdong Province has undoubtedly become the country's largest economic province, with a total of 300 billion U.S. dollars, but it is compared with Bay Area's 1.5 trillion U.S. dollars and Hong Kong Island's 800 billion U.S. dollars.
There is still a huge gap. After all, they are the Four Little Dragons, and now Guangdong Province can only be regarded as a python.
But how much did they have in the early days of reform and opening up? It was less than 20 billion US dollars, which means that their economic aggregate expanded more than ten times in twelve years.
In the past ten years, the average annual economic growth rate of Guangdong Province has exceeded 30%, and the fastest one year has even reached 40%. This is a terrifying number. At this rate of development, it only takes two or three years.
The time can be doubled, which is simply terrifying.