国产精品国产自产 I 96亚洲精品久久久蜜桃 I 涩视频在线 I 翔田千里精品久久一区二 I 337p日本欧洲亚洲大胆 I 字幕日韩视频一区二区 I 日韩偷拍一区二区 I 免费一级大片 I 九九久久精品国产av片国产 I 午夜福利92国语 I 国产免费97 I 波多野结衣福利视频 I 男人和女人在羞羞视频 I 久久精彩视频 I 忘忧草社区中文字幕www I 日韩影视一区二区三区 I 青青av I 国产av熟女一区二区三区 I 亚洲日韩片无码中文字幕 I 懂色av一区二区三区四区 I 国产伦人人人人人人性 I 91亚洲黄色 I 人妻丰满熟妇av无码区免 I 中文字幕人成人乱码亚洲电影 I 大伊人久久 I 免费人成在线观看网站品爱网 I 黄色三级免费片 I 我看午夜视频 I 性欧美色图 I 日韩三级一区二区

Rubber products are of various types, which can be seen everywhere in real life, such as rubber sealing strip, rubber package iron parts, rubber seals, gaskets, rubber sealing rings, rubber toys, rubber miscellaneous parts, etc.. While rubber products in the selection of material production, because rubber products are used in different parts and different functions, we need to have different ways to choose different rubber products. Such as rubber sealing strip, rubber plug, rubber kit, rubber sealing products, etc. Today xiaobian will tell you about the choice of various rubber products

1) How to correctly choose rubber products

Choose rubber, mainly from the production of rubber products performance decision.

1, temperature performance. Whether the rubber parts work at high temperature or low temperature.

2. Extreme temperature, which is different from temperature resistance, should be considered as the most extreme temperature requirements and maintenance time of rubber parts operation;

3, the working medium of rubber parts, is in ordinary air, or in hot air, or in what solution, such as oil, etc.;

4, mechanical action requirements, such as tires to consider contact with the ground, to consider friction; Oil seal to consider the reciprocating compression of the contact machine;

5, color: colorless or colored, if colored, light color, or dark color

6, food requirements: whether contact with food, or directly into the human body, such as chewing gum.

7, medical requirements: such as medical rubber supplies and human rubber skin.

8, environmental protection requirements.

9. Processing conditions. If the site and production machinery are limited, it is appropriate to consider the silicon rubber with simple processing mode. If the rubber processing machines such as mixer and calendering are available, the range of choice is relatively wide;

10, economic benefits: a lot of rubber products, can be made of a variety of rubber, choose the required and low-cost materials, so that the material and its use;

2) How to choose the correct rubber gasket

1. The temperature

Rubber gaskets should have a reasonable service life at the highest or lowest operating temperatures. In order to maintain sealing under operating conditions, the rubber gasket material should be resistant to creep to reduce gasket stress relaxation. Most rubber gasket materials do not exhibit large creep at room temperature, but creep becomes severe as temperatures rise (above 100 ° C) except for most metal gaskets. Therefore, the creep relaxation performance of gaskets at different temperatures is the most easy to distinguish the quality of gaskets. In addition to the maximum or minimum operating temperature that can be tolerated in the short term, consideration should be given to the temperature at which continuous operation is allowed, usually below the maximum operating temperature and above the minimum operating temperature.

Pressure of 2.

Rubber gaskets must bear maximum working pressure. This pressure may be the test pressure, as it may be 1.25 to 1.5 times the maximum working pressure. For gaskets of non-metallic materials, because of its P×T value has a limit value, so when selecting its maximum working pressure, the maximum working temperature that gaskets can withstand, especially saturated water vapor, should be considered. The higher the steam pressure, the higher the steam temperature.

3. The security

Rubber gaskets are required for greater safety if they are used to seal highly toxic chemicals. For example, for the liquefied gas system, it is better to choose the wound gasket, and it is appropriate to choose the form of outer ring, so that it has higher blowing resistance. In addition, the oil refinery, there are fire protection requirements.

4. The economy

Although rubber gaskets are relatively cheap, when choosing the quality, type and material of gaskets, the material loss caused by leakage, shutdown loss and the economic consequences caused by major damage should be taken into account, and the performance and price ratio of gaskets should be considered comprehensively

5. Factors of material and structural form

Cyclic load If there are frequent temperature and pressure fluctuations, the rubber gasket must have sufficient resilience. Vibration If the pipeline vibrates, the rubber gasket must be able to withstand repeated high cyclic stresses. If the sealing medium is drinking water, plasma, drugs, food, beer, etc., we should consider the chemical pollution medium of gasket materials, and use PTFE or rubber and other materials in accordance with the requirements of food and medical health.

3) How to choose the right rubber strip

The purchase of rubber strip is actually very simple, usually summed up as look, smell, ask, cut four steps.

1, look at the material and technology

Look at the material: different uses of rubber strip its material is different, the same kind of rubber strip its image is generally the clearer the better.

Look at the process: see whether the rubber sealing strip surface burr, flat, smooth technical process is conducive to the installation of rubber sealing strip, general consumers can use the combustion method to see the material of the rubber sealing strip.

2. Smell

The smell of good rubber material is obviously different. Usually, the smell of good rubber sealing strip is not so big. On the contrary, the smell of bad rubber sealing strip is big and bad.

3. Ask where the rubber comes from

Detailed knowledge of rubber raw materials and origin, such as origin, characteristics and use, etc.

4. Weigh in

Under normal circumstances, the weight of rubber strips of the same material is basically the same.

4) How to correctly choose rubber seals

1, in the selection of rubber sealing ring, first of all to consider the compatibility with the working medium.

To consider the sealing pressure, temperature, continuous working time, operating cycle and other working conditions. If used in rotation, the temperature rise due to frictional heat should be considered. The physical and chemical properties of different sealing materials are different.

Seal form

According to the load type can be divided into static seal and dynamic seal; According to the sealing use can be divided into hole sealing, shaft sealing and rotating shaft sealing; According to its installation form can be divided into radial installation and axial installation. Radial installation, for shaft sealing, should make the rubber sealing ring diameter and sealing diameter D2 deviation as small as possible; For holes to be sealed, the inner diameter should be equal to or slightly less than the diameter d1 of the groove.

3. Factors affecting the performance of rubber sealing ring.

(1) hardness

The hardness of rubber sealing ring material is the most important index to evaluate the sealing performance. The hardness of rubber sealing ring determines the compression amount of O-ring and groove maximum allowable extrusion clearance.

② Extrusion clearance

System pressure, rubber sealing ring cross section diameter and material hardness. Generally, the higher the working pressure, the smaller the maximum allowable extrusion gap gmax value. If the clearance G exceeds the allowable range, it will lead to the extrusion and even damage of the rubber seal ring.

③ Compression deformation

Under pressure, in order to prevent plastic deformation. The large compression allowed by the rubber seal ring is about 30% in static seal and 20% in dynamic seal.

(4) the amount of pre-compression

In order to ensure the sealing of the groove of the rubber sealing ring, an initial compression amount should be reserved. The pre-compression amount relative to the diameter of the section is usually about 15%~30% in the static seal and 9%~25% in the dynamic seal.

⑤ Stretching and compression

For the hole seal, the rubber seal ring is in a stretch state, the maximum allowable stretch is 6%, for the shaft seal, the rubber seal ring is compressed along the circumference direction, the maximum allowable circumference compression is 3%.

5) Pay attention to the purchase of rubber products

1, pay attention to cracked rubber products

Now a large number of rubber products on the market in the market, because of rubber products in the installation, may occur cracking and falling off and other phenomena, so in the purchase should refuse to bad rubber products.

2, pay attention to the specifications of rubber products

Specification is the key to the purchase of rubber products, the rubber products manufacturers usually have their own standards, or customer customized rubber products standard. Its market has many standard thickness specifications, such as inaccurate size, after use will appear arch, installation is not on the phenomenon, and so on, but also will produce sound, its use will emit squeak and other problems

3, pay attention to the material

Material will determine the physical performance, grade, use and service life of rubber products, in many cases, in order to achieve beautiful effect, the physical performance of the material has been tested in many ways.

4. Know the names of rubber products

No matter what kind of rubber products you buy, you have to let the manufacturer write the name of the rubber products in the contract and sales list. Once the article number is found wrong, you can claim double compensation from the manufacturer.

5. Deny package products

Now there are a lot of rubber products on the market is through some agents without manufacturers, packaging will be made into their own brand. Such manufacturers aim to make money and cannot guarantee quality at all. If appear a problem, push its to manufacturer body, must see there is no factory address on packing case so when choose and buy, sign a contract, the manufacturer telephone that wants him when making deposit, verify manufacturer with spot.