1、 Overview of the Bearing Industry
1. Overview of the Development of the Bearing Industry
Bearings are the components that carry shafts, known as the "joints of machinery", and are an essential basic component in modern mechanical equipment. The main function of a bearing is to support a rotating shaft or other moving body, guide rotational or mobile motion, and bear the load transmitted from the shaft or its components.
The modern industrial bearing industry emerged from the late 19th century to the early 20th century. Since the 1950s, with the rapid development of high-tech industries such as aerospace, nuclear energy, electronic computers, optoelectronic magnetic instruments, and precision machinery, the world's bearing industry has entered a period of comprehensive innovation. Manufacturing technology has developed rapidly, and the variety, bearing accuracy, performance, and service life have become increasingly mature and perfect.
Before the 1960s, the bearing industry was mainly monopolized by European and American countries. After the 1960s, Japan gradually replaced the monopoly position of European and American countries in the field of micro and small bearings. After entering the 1990s, with the continuous progress of production technology in China, Chinese bearing enterprises began to compete comprehensively with foreign enterprises in the field of micro and small bearings.
According to the National Bureau of Statistics, the main business revenue of China's bearing industry from January to October 2015 was 222.549 billion yuan. In 2014, the main business revenue was 274.1 billion yuan, an increase of 222.5 billion yuan from 51.6 billion yuan in 2005, with a compound growth rate of 18%. It is expected that the growth rate of bearings will slow down in the future, but because bearings are essential components in various machinery, the growth rate will not be lower than the GDP growth rate.
2. Classification of Bearing Products
There are many specifications and models of bearing products, which can be divided into two categories based on their structure and working principle: "rolling bearings" and "sliding bearings". Rolling bearings refer to bearings that contain rolling elements between parts for rolling motion, while sliding bearings are bearings that do not use rolling elements and only work under sliding friction.
Rolling bearings have the advantages of low friction coefficient, high transmission efficiency, and good mechanical performance, and are currently the dominant type in the bearing industry. Rolling bearings have achieved standardization, serialization, and universality, suitable for large-scale production and supply, promoting the comprehensive development of the bearing industry.
Sliding bearings have the advantages of small size, high load-bearing capacity, low vibration, low noise, and multiple structural changes. Therefore, in situations with high load-bearing capacity, compact structural requirements, and impact loads, sliding bearings have significant advantages over rolling bearings. The advantage of the variable structure of sliding bearings also makes them applicable to various mechanical parts of different shapes.
According to the different lubricating materials and lubrication methods, sliding bearings can be further divided into two categories: "self-lubricating bearings" and "general sliding bearings". Traditional sliding bearings require the addition of lubricating materials such as oil and grease before or during operation, in order to form a fluid or semi fluid film at the friction interface and provide effective lubrication, known as "general sliding bearings". Thick walled bearings, thin-walled bearings, etc. belong to general sliding bearings. And self-lubricating bearings are a new type of product in sliding bearings, which use self-lubricating materials as lubricants or are pre filled with lubricants and sealed, and can be used for a long time without adding lubricants during operation. The bearings made with solid self-lubricating materials as lubricants are also known as "oil-free bearings" because they do not require the addition of traditional lubricants such as oil and grease. At present, the main raw materials commonly used in the production of self-lubricating bearings in the world include metal materials such as copper and steel, as well as non-metallic materials such as polymer products (polytetrafluoroethylene) and graphite.
3、 Overview of the self-lubricating bearing industry
1. Development of self-lubricating bearings
The manufacturing technology of self-lubricating bearings originated in the UK. In the 1950s, PTFE (polytetrafluoroethylene) began to be tested as a bearing material in the UK, and breakthroughs were also made in copper powder sintering technology. In 1956, the world's first self-lubricating DU bearing with PTFE lining and steel plate support was launched on the market. In the late 1960s, self-lubricating bearings began to enter cutting-edge technological applications such as aerospace. Since the 1970s, British self-lubricating bearing manufacturers have licensed their technology to companies in France, Germany, Japan, and the United States. This move has driven the rapid development of the world's self-lubricating bearing industry, and self-lubricating bearings have gradually entered all mechanical manufacturing fields.
2. Classification of self-lubricating bearing products
With the development of the self-lubricating bearing industry, the production process and materials of self-lubricating bearings are constantly innovating, and the types of products are gradually becoming more diverse. According to the different product structures and manufacturing materials, self-lubricating bearings are divided into three major categories: multi-layer, single-layer, and others, which are further divided into multiple subcategories. Specifically, as shown below:
The "multi-layer" self-lubricating bearing product is composed of two or more different types of bearing materials stacked and compounded, where the lining material plays a self-lubricating role, the substrate plays a supporting role, and other materials play a connecting and transitional role. The lubrication effect of "laminated" products is excellent, and their load-bearing capacity is determined by the compressive strength of the surface material. According to the categories of substrate and liner materials, they can be divided into metal substrate and metal liner composite, metal substrate and non-metal liner composite, and non-metal substrate and non-metal liner composite.
The "single-layer" self-lubricating bearing product is made of a type of bearing material, which relies on self-lubricating materials such as graphite, molybdenum disulfide, polytetrafluoroethylene, lead, etc. contained in the bearing material for lubrication. According to the type of bearing material, it can be divided into metallic and non-metallic categories. Non metallic single-layer self-lubricating bearings mainly include integral non-metallic bearings, non-metallic rolled bearings, etc. Metal single-layer bearings mainly include solid embedded products and oil containing products. Solid inlaid self-lubricating bearings are pre processed holes or grooves in a certain arrangement on a metal substrate, and then solid lubricants are embedded in them; During the working process, due to frictional heat or environmental temperature, solid lubricants protrude slightly on the sliding surface and form a transfer film on the metal substrate and mating surface through friction, thereby reducing friction and wear resistance. Oil containing self-lubricating bearings are made by pressing and sintering metal powder into a porous material through powder metallurgy technology, and then filling the pores with lubricating oil; During the working process, due to frictional heat or environmental temperature, lubricating oil precipitates from the bearing, forming a lubricating oil film on the metal substrate and mating surface, thus playing a role in reducing friction and wear resistance.
3. Characteristics of self-lubricating bearing products
Self lubricating bearings are suitable for places where refueling is impossible or difficult. Due to the requirements of special production processes, certain key equipment in automobile manufacturing and machinery industry enterprises need to operate under extreme working conditions. Due to various factors such as heavy equipment, high ambient temperature, large dust, or acidic corrosive gases in the air, it is difficult to add lubricating oil to the equipment. Therefore, rolling bearings or general sliding bearings have severe friction and wear, which can easily cause bearing bites or death, resulting in part wear and damage, leading to equipment shutdown. In order to produce continuous operation, in addition to requiring the installation of multiple equipment for wheel repair in the original design, a large number of maintenance personnel are also required, and spare parts and energy consumption are extremely high. Therefore, enterprises in the automotive manufacturing, engineering machinery, and mold industries all have a demand for special lubricating materials under complex working conditions. Oil free design can greatly simplify bearing design, structure, etc., reduce costs, save design time, and eliminate the risk of insufficient oil supply when using bearings without or with minimal maintenance. The issuer has achieved innovative breakthroughs in material formulation and preparation processes through research on self-lubricating bearing composite materials and self-lubricating bearings, which can solve lubrication problems for customers under special working conditions.
Due to the fact that self-lubricating bearings do not require oil supply devices, there is no need to add oil during operation, which can save a lot of installation and operating costs, improve mechanical performance, and enhance service life and reliability. Oil free treatment does not require waste oil recycling and is also beneficial for environmental protection. Self lubricating bearings have lower hardness requirements for grinding shafts, thereby reducing the difficulty of machining related parts. In the self-lubricating composite bearing structure, the surface can be electroplated with various metals and can be used in corrosive media. In addition, due to oil-free lubrication, there is no problem of oil evaporation, and self-lubricating bearings can be used in high temperature and high pressure environments.
3、 Overview of the self-lubricating bearing industry
1. Development of self-lubricating bearings
The manufacturing technology of self-lubricating bearings originated in the UK. In the 1950s, PTFE (polytetrafluoroethylene) began to be tested as a bearing material in the UK, and breakthroughs were also made in copper powder sintering technology. In 1956, the world's first self-lubricating DU bearing with PTFE lining and steel plate support was launched on the market. In the late 1960s, self-lubricating bearings began to enter cutting-edge technological applications such as aerospace. Since the 1970s, British self-lubricating bearing manufacturers have licensed their technology to companies in France, Germany, Japan, and the United States. This move has driven the rapid development of the world's self-lubricating bearing industry, and self-lubricating bearings have gradually entered all mechanical manufacturing fields.
2. Classification of self-lubricating bearing products
With the development of the self-lubricating bearing industry, the production process and materials of self-lubricating bearings are constantly innovating, and the types of products are gradually becoming more diverse. According to the different product structures and manufacturing materials, self-lubricating bearings are divided into three major categories: multi-layer, single-layer, and others, which are further divided into multiple subcategories. Specifically, as shown below:
The "multi-layer" self-lubricating bearing product is composed of two or more different types of bearing materials stacked and compounded, where the lining material plays a self-lubricating role, the substrate plays a supporting role, and other materials play a connecting and transitional role. The lubrication effect of "laminated" products is excellent, and their load-bearing capacity is determined by the compressive strength of the surface material. According to the categories of substrate and liner materials, they can be divided into metal substrate and metal liner composite, metal substrate and non-metal liner composite, and non-metal substrate and non-metal liner composite.
The "single-layer" self-lubricating bearing product is made of a type of bearing material, which relies on self-lubricating materials such as graphite, molybdenum disulfide, polytetrafluoroethylene, lead, etc. contained in the bearing material for lubrication. According to the type of bearing material, it can be divided into metallic and non-metallic categories. Non metallic single-layer self-lubricating bearings mainly include integral non-metallic bearings, non-metallic rolled bearings, etc. Metal single-layer bearings mainly include solid embedded products and oil containing products. Solid inlaid self-lubricating bearings are pre processed holes or grooves in a certain arrangement on a metal substrate, and then solid lubricants are embedded in them; During the working process, due to frictional heat or environmental temperature, solid lubricants protrude slightly on the sliding surface and form a transfer film on the metal substrate and mating surface through friction, thereby reducing friction and wear resistance. Oil containing self-lubricating bearings are made by pressing and sintering metal powder into a porous material through powder metallurgy technology, and then filling the pores with lubricating oil; During the working process, due to frictional heat or environmental temperature, lubricating oil precipitates from the bearing, forming a lubricating oil film on the metal substrate and mating surface, thus playing a role in reducing friction and wear resistance.
3. Characteristics of self-lubricating bearing products
Self lubricating bearings are suitable for places where refueling is impossible or difficult. Due to the requirements of special production processes, certain key equipment in automobile manufacturing and machinery industry enterprises need to operate under extreme working conditions. Due to various factors such as heavy equipment, high ambient temperature, large dust, or acidic corrosive gases in the air, it is difficult to add lubricating oil to the equipment. Therefore, rolling bearings or general sliding bearings have severe friction and wear, which can easily cause bearing bites or death, resulting in part wear and damage, leading to equipment shutdown. In order to produce continuous operation, in addition to requiring the installation of multiple equipment for wheel repair in the original design, a large number of maintenance personnel are also required, and spare parts and energy consumption are extremely high. Therefore, enterprises in the automotive manufacturing, engineering machinery, and mold industries all have a demand for special lubricating materials under complex working conditions. Oil free design can greatly simplify bearing design, structure, etc., reduce costs, save design time, and eliminate the risk of insufficient oil supply when using bearings without or with minimal maintenance. The issuer has achieved innovative breakthroughs in material formulation and preparation processes through research on self-lubricating bearing composite materials and self-lubricating bearings, which can solve lubrication problems for customers under special working conditions.
Due to the fact that self-lubricating bearings do not require oil supply devices, there is no need to add oil during operation, which can save a lot of installation and operating costs, improve mechanical performance, and enhance service life and reliability. Oil free treatment does not require waste oil recycling and is also beneficial for environmental protection. Self lubricating bearings have lower hardness requirements for grinding shafts, thereby reducing the difficulty of machining related parts. In the self-lubricating composite bearing structure, the surface can be electroplated with various metals and can be used in corrosive media. In addition, due to oil-free lubrication, there is no problem of oil evaporation, and self-lubricating bearings can be used in high temperature and high pressure environments.
