When the designed gear transmission works under unstable load or the two-phase meshing gears are all hard tooth surfaces (HB>350), in order to make the failure not concentrated on certain gear teeth and scrapped in advance, one of the gears should be used. Any tooth of a gear has an equal chance of meshing with any tooth of another gear that meshes. In this case, the selection principle of the gear ratio is: the number of teeth of the two gears is relatively prime. Generally, the common divisor of adjacent gear teeth is required to be as small as possible, so that the deformation on one tooth can be evenly ground to as many teeth as possible.
When the designed gear transmission works under unstable load or the two-phase meshing gears are all hard tooth surfaces (HB>350), in order to make the failure not concentrated on certain gear teeth and scrapped in advance, one of the gears should be used. Any tooth of a gear has an equal chance of meshing with any tooth of another gear that meshes. In this case, the selection principle of the gear ratio is: the number of teeth of the two gears is relatively prime. Generally, the common divisor of adjacent gear teeth is required to be as small as possible, so that the deformation on one tooth can be evenly ground to as many teeth as possible.
The rise and fall of the price of silicone rubber is mainly related to methyl vinyl silicone rubber (raw rubber raw material), because raw rubber is the main raw material for the production of silicone rubber.
Secondly, it is also related to factors such as tensile strength of silicone raw materials, hardness of silicone raw materials, different types and varieties of silicone raw materials, logistics and transportation costs, and market supply and demand.
1. The raw rubber is mainly produced from raw rubber, so the price change of raw rubber is the main factor affecting the price of raw rubber. And the price of raw rubber is quoted according to the weekly market changes, and the price of raw rubber varies greatly. Today, the price of silica gel raw materials is still running at a high level.
2. The tensile strength of silicone raw materials, when customers purchase silicone raw materials, the quality is mainly based on the tensile strength. The quality system of silica gel raw materials is mainly divided into three types: powder glue, precipitation glue and gas-phase glue. Powder glue is produced by adding a certain proportion of silica powder. It is produced by fumed silica, the tensile strength is 6Mpa-8Mpa, the quality and price are moderate, and it is the most widely used; fumed silica is produced from fumed silica. The produced fumed adhesive has good tensile strength and transparency. The tensile strength is generally 7Mpa-9Mpa, which is expensive and generally only used for high-standard products.
3. The price of silicone raw materials with different hardness is also different, because the higher the hardness, the lower the glue content, and the lower the hardness, the higher the glue content. Therefore, the higher the hardness in the precipitation glue, the cheaper the price. The higher the hardness in fumed rubber, the more expensive the price is because the price of precipitated silica is lower than that of raw rubber, while the price of fumed silica is higher than that of raw rubber.
4. Silica gel raw materials are divided into different models according to their functional uses, mainly divided into food grade silica gel, high temperature resistant silica gel, insulating silica gel, flame retardant silica gel, sulfur-added color silica gel, etc. The auxiliary materials added are also different, so the price of silicone raw materials of different models is also different.
5. The cost of logistics and transportation also slightly affects the price of silica gel raw materials. It mainly depends on the distance of transportation. The closer the distance is, the more affordable the price is. On the contrary, the price of silica raw materials should be appropriately increased for the farther the distance.
6.The price increase is still related to market supply and demand. If the market is prosperous, it will lead to a surge in silicone rubber compound raw materials.
Nowadays, the sales market of silicone raw materials is very clear, and many manufacturers charge shoddy products in order to increase sales. Customers will be deceived if they pursue affordable prices. As the saying goes, you get what you get for every penny. This sentence is just right for silicone raw materials. Only good quality, affordable price, and high-quality service can meet the basic needs of users.
Silicone tube is a kind of rubber with good comprehensive performance, which has excellent electrical insulation performance, aging resistance, chemical stability, oxidation resistance and weather resistance and good air permeability. It can be used for a long time at -40℃～240℃. Therefore, silicone tubes are also widely used in modern industries and daily necessities such as aviation, electronics, chemicals, machinery, and electrical appliances.
With the wide use of silicone tubes in our daily life, people pay more and more attention to the choice of silicone tubes. So, how do we choose a good silicone tube in our daily life?
Distinguish from smell: Good silicone tubes are generally free of pungent odor, environmentally friendly, non-toxic, and have good texture.
Distinguish from brightness: good silicone tube has better permeability, high color firmness of silicone tube, and the natural color of silicone tube can also be adjusted according to the user’s needs.
Distinguish from elasticity: Good silicone tubes generally have better toughness. When we pull hard, if white spots appear, it is a poor quality silicone tube.
Color: Generally, the silicone tube is colorless and transparent except for the customizable color. If the color changes seriously after long-term use, the quality is poor.
Of course, in addition to the above four identification methods, if you want to quickly and easily choose a good silicone tube, the best way is to choose a well-known brand of silicone tube.Linhai Haihua Rubber & Plastic Products Co., Ltd. was founded in 1980. It is a professional manufacturer of all kinds of automobile rubber tubes and rubber&plastic parts. Since 1989, it has become a formal supplier for Dongfeng Motor Company. At present, it is supporting dozens of domestic and foreign main engine factories, such as Cummins, Xiamen Jinlong, Yangzhou Yaxing, etc. The company has 18 million RMB fixed assets and 8000 square meters of plant area. There are more than 20% professional and technical personnel in the company.Ithas got the certificate of ISO9002, ISO9001:2000, QS9000, FIA16949 and so on.
Silicone tube is a kind of special rubber with a wide range of comprehensive properties. It has excellent electrical insulation properties, aging resistance, chemical stability, oxidation resistance, corrosion resistance, radiation resistance, physiological inertness, good air permeability, high and low temperature resistance, and can be used in -60℃～250℃ for long-term use. Therefore, it is widely used in aviation, electronics, petroleum, chemical industry, machinery, electrical appliances, medical, oven, food and other modern industries, defense industries and daily necessities. Before the corrosion-resistant silicone tube appeared on the market, people used more rubber tubes for use, and the emergence of silicone tubes gradually replaced rubber tubes. Silicone tube is a new type of silicone tube that is more advanced and more environmentally friendly and healthy that people have discovered in the development process of industrial production. In the past, people’s reliance on rubber pipes can be said to be very large. Even now, there are still many factories using rubber pipes, but in the future, corrosion-resistant silicone pipes will inevitably replace rubber pipes and become the mainstream of industrial production.
Corrosion-resistant silicone tube is a kind of imported silicone, which is made by advanced scientific production technology, and corrosion-resistant silicone tube is a kind of silicone tube with strong corrosion resistance, which is more corrosion-resistant than ordinary silicone tube. better. The rubber tube also has the performance characteristics of corrosion resistance, so it is possible to compare the two to find out what is the difference between the corrosion-resistant silicone tube and the corrosion-resistant rubber tube, and what are the differences between the two?
Judging from the material of the most basic raw materials, the corrosion-resistant silicone tube is a completely odorless, non-toxic, high-transparency, and flexible silicone tube, while the rubber tube has a pungent smell. The most advanced production technology can not be eliminated, so from this aspect, the silicone tube is more environmentally friendly than the rubber tube. Moreover, the flexibility of the corrosion-resistant silicone tube will be better, and the mechanical properties of the rubber tube will be better.
In terms of corrosion resistance, the corrosion resistance of silicone tube is better than that of rubber tube. Of course, relative to corrosion resistance, it is related to the use environment and method of use of the product. There are no specific indicators for the specific use of this. Both have good corrosion resistance, of course, the relative corrosion resistance of silicone tube will be better. Regardless of the environment, the corrosion resistance of the silicone tube maintains good test data.
In the future industrial production, the corrosion-resistant silicone tube will inevitably be a trend, and it will gradually replace the rubber tube and become the only product used in industrial production, and only in this way can it better meet the needs of industrial manufacturers.
If the hardness of the silicone tube is not enough, how can we increase the hardness of the silicone tube and test the hardness of the silicone tube? First of all, because the main components of the silicone tube are vinyl and hydrogen-containing silicone oil, the vinyl content and hydrogen-containing silicone oil can be appropriately increased during production, and some silica and fineness can be added. At the same time, wollastonite powder can also be added. to increase the hardness, but it should be decided according to the needs of customers.
Secondly, there are three hardness testing methods for silicone tubes, namely: Shore hardness testing method, Shore hardness testing method and Rockwell hardness testing method.
Shore hardness test method: It is a dynamic force test, which is essentially different from other static force test methods. It is mainly suitable for determining the Shore hardness value of ferrous and non-ferrous metals. Shore hardness tester is easy to carry, especially suitable for medium and large workpieces in metallurgy and heavy machinery industries, such as large components, castings, forgings, crankshafts, rolls, oversized gears, machine tool guide rails and other workpieces.
Shore hardness test method: refers to the reading of the value measured by the Shore hardness tester, its unit is “degree”, and its description methods are divided into two types, A and C, which represent different hardness ranges. A hardness tester is used to test and obtain the data, and the foamed silicone tube is tested with a Shore C hardness tester and the data is obtained. Therefore, in general, for a rubber or plastic product, when testing, the tester can decide whether to use a Shore A durometer or a Shore C durometer to test according to whether the silicone tube is foamed.
Rockwell hardness test method: use a diamond cone with an apex angle of 120 degrees or a steel ball with a diameter of 1.59mm/3.18mm, press it into the surface of the tested material under a certain load, and obtain the hardness of the material from the depth of the indentation .
Finally, the above points are the methods to increase the hardness of silicone tubes and several methods to test the hardness of silicone tubes. Our factory can make design plans according to the needs of customers. Welcome to visit our website www.hiwowsport.com to leave a message.
In addition to the characteristics of high strength, low noise, simple and convenient installation and disassembly, good fire resistance, long service life, good flexibility and shock resistance, the T-clamp rubber joint connection also has the characteristics of synchronization.
The interface is fastened with external bolts, which avoids the defects that the flexible interface flange of the socket and socket is easily damaged and the bolts against the wall anchor are difficult to fix, and it has the advantages of convenient operation and so on.
Clamp-type rubber joints use clamps instead of flanges and bolts. During installation, the two pipe ports of the clamp-type rubber joints can be respectively fitted on the pipes to be connected, and the rubber joints can be fixedly connected to the pipes through the clamps. .
The interface of the clamp rubber joint is fastened with bolts, which avoids the defects that the flexible interface flange of the socket and socket is easily damaged and the anchor bolts are difficult to fix, and has the advantages of simple operation.
The parts of the clamp rubber joints should be kept away from heat sources and ozone areas. It is strictly forbidden to expose to strong radiation and use media that do not meet the requirements of this product.
It is strictly forbidden to use sharp tools to scratch the outer surface and sealing surface of the clamp rubber joint during transportation, loading and unloading.
We often hear people say don’t wait until the oil light is on before adding oil. Doing so will cause the Fuel Pump to overheat and cause damage, which will cause damage to the oil pump in the long run. The reason is that the Fuel Pump needs to be soaked in gasoline to dissipate heat. When the light is on, too little gasoline in the fuel tank will cause the motor in the fuel pump to fail to dissipate heat properly, causing damage. So is that really the case?
First of all, it must be said that the motor in the Fuel Pump does need heat dissipation, but it does not rely on the fuel near the oil pump to dissipate heat. In addition, some oil pumps are very tall and run through the entire height of the fuel tank from top to bottom. The heat-dissipating motor is placed in the middle and lower position of the fuel pump. When the fuel is still one-third left, the motor is no longer immersed in gasoline. In fact, the motor relies on the oil sucked in by the oil pump to dissipate heat: gasoline is sucked into the oil pump and sent to the engine, which also takes away the heat of the oil pump, so as long as the oil pump can still absorb oil, it will dissipate heat normally and work normally .
Therefore, what can really cause the oil pump to overheat is actually when the oil pump cannot absorb oil, but instead sucks in air (or sludge), then there will be a hidden danger of oil pump damage. That is to say, as long as you don’t drive the car to a completely out of fuel state, basically ordinary lights will not cause any damage to the Fuel Pump. And to let the oil pump rise to the sky, it is estimated that the overheating caused by the intake of air will cause the oil pump to be damaged.
In addition, the fuel tank design of today’s cars is quite sophisticated, which basically prevents the fuel pump from “starving” until the fuel tank is almost empty. Therefore, as long as you don’t drive the car until it is completely out of fuel, theoretically, the fuel pump will not be damaged, and the fuel meter will not be damaged until the fuel meter lights up.
Since the fuel tank is on the opposite end of the car from the engine, a fuel pump is required to direct gasoline to the engine. There are two types: mechanical (for carbureted vehicles) and electric (for cars with electronic fuel injection systems). Auto mechanics should use electronic fuel pumps. A carburetor is a fuel delivery mechanism that uses a simple vacuum principle to deliver fuel to the engine. The vacuum that draws the air-fuel mixture into the engine also draws fuel down the line into the engine. Since the system does not use a pre-existing force (such as a vacuum) to draw fuel down the line, the fuel pump must be located at the fuel source, either inside or next to the fuel tank.
A mechanical fuel pump (for carbureted vehicles) is a fuel delivery mechanism that uses a simple vacuum principle to deliver fuel to the engine. The vacuum that draws the air-fuel mixture into the engine also draws fuel down the line into the engine. However, extra help is needed, so a carburized engine has a mechanical fuel pump that relies on the rotation of the engine, so, in a carburized car, it sits next to the engine. The carburetor ensures that the proper mixture of gasoline and air enters the engine for combustion.
Electronic fuel injection by electric fuel pump (for cars with electronic fuel injection system) is a delivery system that injects a fine mist of fuel into the combustion chamber of an engine. Controlled by a computer, the system closely monitors factors such as throttle position, air-fuel ratio and displacement. Since the system does not use a pre-existing force (such as a vacuum) to draw fuel down the line, the fuel pump must be located at the fuel source, either inside or next to the fuel tank. The fuel pump is electronic, which means it is driven and controlled electronically. At times, its work can be identified by a soft but steady hum from the rear of the car.
Fuel pump failures are not uncommon, especially in cars equipped with electronic fuel injection systems. Usually when it breaks down the car crackles and dies, basically a car with this kind of breakdown, even if it has gas in the tank, acts as if it’s out of gas. Fuel pump failure can be checked by checking the system’s Check the fuel delivery side to confirm; if no fuel is delivered to the engine, the fuel pump is likely to be faulty. Replacing an electronic fuel pump can be a tricky job. In some cars, the electronic fuel pump is located in an area that is easily accessible from under the car. Other vehicles have an access panel on the inside of the car that can be removed to access the fuel pump. There are also cars that require the tank to be siphoned and removed, or removed before accessing the fuel pump. The latter type of car is usually the most laborious replacement job.
Does the car have a hard time accelerating (especially on the highway)? Is your car showing signs of low fuel? The fuel line, filter, pump or injector is most likely blocked or partially blocked. If you can’t start your car at all, you might want to do a quick fuel pump test to see if that’s the culprit.
1.Conduct electrical testing
①Check fuel pump fuse.
Often it is not the fuel pump that fails, but the power supply. Consult the owner’s manual to find the location of the fuse box, and then find the fuse that corresponds to the fuel pump. Remove the fuse and check for signs of failure. Fuses may melt or blow. If the fuse appears to be OK, check other fuse parts associated with the fuel system for signs of wear and replace them if necessary.
·If you need to replace the fuse, make sure to use one with the proper current rating. Do not install a fuse with an excessively rated current.
·A blown fuse could mean that the circuit is drawing too much current, and you need to check individual circuits. When checking the relay, get someone to start the car for you, or take it to a repair shop.
②Check fuel pump voltage.
The current flowing through the circuit won’t necessarily go to the fuel pump, so you’ll have to check the voltage too. Look through your car’s manual to see which parts you need to inspect and the correct inspection procedure.
·Test the voltage source to see if current leaves the fuse to the fuel pump.
③Use a voltmeter to perform a voltage drop test.
Make sure the wires have enough voltage and the ground wire is properly grounded. If the electrical test results show that everything is OK, it is likely that the fuel pump is faulty and needs to be replaced. You can additionally perform an oil pressure test for a more comprehensive check.
·If the voltage difference exceeds 1 volt, the wire may be corroded, or there may be a problem with the positive or negative side of the circuit. Take it to a repair shop for more in-depth testing and further advice.
2.Carry out an oil pressure test
①Possibility of drain filter failure.
A clogged filter with sediment can also make it difficult for the car to accelerate (and you suspect the problem is the fuel pump). Check the short inlet hose and blow air into it to make sure there isn’t much resistance. Check the filter screen for debris and replace the filter if necessary.
②Buy a fuel pressure gauge.
Most auto parts stores sell fuel pressure gauges. It’s a good investment, and it works on most models. If you don’t want to buy it, you can also borrow it from a mechanic or auto store that allows customers to borrow tools. The oil pressure test only takes a few minutes to complete.
③Connect the pressure gauge to the fuel pump assembly.
Find where the fuel pump is located (usually near the carburetor or injector) and find where the fuel pump connects to the filter housing. There should be a small connector there to connect a pressure gauge.
·Each gauge may be used slightly differently, and the location of the fuel pump varies from car to car, so consult your car’s manual for more details.
④Get someone to start the engine for you while you check the pressure gauge.
Let the engine warm up a little and check the oil pressure when the car is running at idle and rated rpm (see fuel pump specs). If you don’t know the rated rpm, just start the engine and see what the oil pressure makes a difference. If the problem is serious and the needle on the pressure gauge doesn’t move, then you need to replace the fuel pump.
·The oil pressure must meet the specifications listed in the owner’s manual, and when the engine runs to a certain level, the oil pressure should also increase. If the oil pressure does not increase, or the difference between the inlet and outlet pressures exceeds 28 kPa (4 psi), then you need to replace the fuel pump.
