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Dongguan Mingzhen Rubber & Plastic Products Co., Ltd.

18 yearsFocus on R & D and production of silicone rubber products

Become a respected supplier of silicone rubber products

Service Hotline:

+86-136 6988 8704

Dongguan Mingzhen Rubber & Plastic Products Co., Ltd.
18 years focus on silicone rubber products research and development and production
Professional customization

Dongguan Minz Rubber & Plastics Co., Ltd.

Add.: No.4, New Industrial Road, Shipai Tangwei, shipai town, Dongguan City
Tel: +86-0769-8665 2688
Fax: +86-796-8180 6477
Contact: Miss Li +86-136 6988 8704
Mailbox:lixiaoxia@dgminz.com.cn

How the viscoelasticity of the silicone seal ring is composed

How the viscoelasticity of the silicone seal ring is composed

2021-06-29 11:12:32

The initial contraction of the O-ring seal operating at minus temperature may be reduced or completely disappeared due to the sharp drop in temperature. Under the condition of -50 ~-60 ℃, the rubber material that is not resistant to low temperature will completely lose the initial stress. Even for the rubber material that is resistant to low temperature, the initial stress at this moment will not be greater than 25% of the initial stress at 20 ℃, because the initial contraction of the silicone seal ring depends on the linear expansion coefficient. The pressure of the working medium is the main factor causing the deformation of the silicone sealing ring. The working pressure of modern hydraulic equipment is increasing day by day. The long-term high-pressure action of the sealing ring will deform the silicone sealing ring. Therefore, the design should be based on the working pressure. Appropriate pressure-resistant rubber materials, the higher the working pressure, the higher the hardness and high pressure resistance of the materials used. In order to improve the pressure resistance of the silicone sealing ring material and increase the elasticity of the material (especially to increase the elasticity of the material at low temperature and reduce the compression deformation of the material, it is generally necessary to improve the formula of the material and add plasticizer. However, if the silicone sealing ring with plasticizer is soaked in the working medium for a long time, the plasticizer will be gradually absorbed by the working medium, resulting in the volume shrinkage of the silicone sealing ring, it is even possible to cause negative compression of the silicone seal ring (I. e., a gap between the silicone seal ring and the surface to be sealed). Because the rubber material used in the silicone sealing ring belongs to the viscoelastic material, the compression amount and rebound blockage set in the initial stage can be used for a long time, resulting in permanent deformation and gradual loss, leakage, permanent deformation and elastic force disappearance are the main reasons for the loss of sealing function of the O-ring. Operating temperature is another important factor affecting the permanent deformation of silicone sealing ring. High temperature will accelerate the aging of rubber materials. The higher the operating temperature, the greater the permanent deformation of silicone sealing ring. When the permanent deformation is greater than 40%, the O-ring will lose its sealing ability and leak. The initial stress value formed in the rubber materials of silicone sealing ring due to contraction deformation, it will gradually decrease and disappear with the relaxation process of silicone sealing ring pressed by silicone keys and the effect of temperature drop.

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The reason why the rubber seal ring feels very important

The reason why the rubber seal ring feels very important

2021-06-29 10:50:34

Good elasticity, tear resistance, good resistance to neutral solvents, heat resistance: silicone rubber has much better heat resistance than ordinary rubber, has high wear resistance, and is worn on the surface of the working seal ring. The part has the function of automatic elastic compensation, thereby increasing the service life of the seal. Equipment and the use of sealing ring should pay attention:. (1) to avoid extended use, dynamic sealing rubber seals use period is generally 3000~5000h, should be replaced in a timely manner. (2) to avoid the use of old silicone sealing ring, the use of new sealing ring, but also carefully check the surface quality of the sealing ring, confirm that no small holes, protrusions, cracks and grooves and other shortcomings and meet the elasticity before use. (3) When replacing the sealing ring, strictly check the sealing ring groove, remove dirt, and polish the bottom of the groove. (4) Do not install the wrong direction and damage the lips. If there are scars of more than 50μm on the lips, it may cause significant oil leakage. (5) Avoid forcing the equipment to be knocked in with a hammer. Instead, special tools should be used to press the sealing ring into the seat hole first, and then a simple cylinder should be used to maintain the lip through the spline. Before the equipment, some lubricating oil should be applied to the lip to facilitate the equipment and avoid burns during initial work. Attention should be paid to cleaning. Silicone products, whether it is stretching, resilience, deformation and toughness strength are very important, if the above performance is basically a good material, O-ring is suitable for installed in a variety of mechanical equipment, at the specified temperature, pressure, and different liquid and gas medium, in the static or motion state from the sealing effect. Silicone sealing ring because of its environmental protection, and the use of a wide range of temperature, can be in the -60 degrees ~ 200 degrees temperature range of long-term use, so the use of more and more widely. Silicone sealing ring is not resistant to oil, and is not suitable for most thick-shrunk solvents, oil products, silicone key thick-shrunk acid and diluted sodium hydroxide.

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What is the cause of the failure of the silicone sealing ring

What is the cause of the failure of the silicone sealing ring

2021-06-23 11:06:27

Influence of hardness and softness of silicone sealing ring: in many cases, the function and structure of the product can be completely changed according to the different softness of silicone products. therefore, the silicone sealing ring will present some problems that cannot be prevented, such as extrusion gap, excessive stress, too high hardness, no rebound of product deformation and other factors, due to the selection of different hardness and softness of silicone sealing ring in the application process. Gap problem of silica gel sealing ring: the gap problem can be divided into several factors. one is the rubber problem of raw materials. many silica gel materials show poor resilience due to formula. the lack of tensile force leads to leakage due to less strength in the application process. the processing problem of silica gel ring manufacturers, such as brittle products, which leads to thinner curling thickness, is easy to present this kind of problem, the soft product leads to the inner bulge of the rubber material, which is not ripe, and the deformation after long-term stretching and compression presents a gap problem. Different sealing methods of silicone sealing ring. Sealing ring 1. Static tight closing: cylindrical static tight closing equipment is the same as reciprocating tight closing equipment, usually W = 10% ~ 15%, and simple surface tight closing equipment W = 15% ~ 30%. 2. As far as dynamic tight closure is concerned, it can be divided into three working conditions:. A. reciprocating motion close tightly usually take W = 10% ~ 15%. B. tight closing of rotary movement must consider the scorched blush effect when selecting the contraction rate. generally speaking, the inner diameter of the o-ring for rotary movement is 3% ~ 5% larger than the shaft diameter, and the contraction rate W = 3% ~ 8% of the outer diameter. C. low friction transport with O-ring, in order to reduce the friction resistance, usually choose a smaller tightening rate, that is, W = 5% ~ 8%. Today's scientific and technological skills, the sealing and protection skills of many products still have certain defects in the actual process, and the selection of silicone (a kind of rubber material) as the raw material of the seal is a common one for us, so silicone sealing ring, as a kind of seal used in many aspects, often presents some unexpected function problems in the normal application process, which cannot reach the actual problems and cannot show the effect of the product. Analysis of the causes of failure in the use of silicone seals.

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Why do silicone seals have different colors

Why do silicone seals have different colors

2021-06-23 10:28:57

Silicone sealing ring is widely used in sealing profession because of its excellent ductility and pressure resistance, and silicone keys can reasonably prevent the leakage of substances. What's more, it is widely used. Therefore, the natural environment in which it is used is often diversified and changeable. This is full of key reasons that cause the ineffectiveness of silicone sealing ring, in which rupture is a key situation of ineffectiveness, the break accounts for more than 80% of the total, so what are the reasons for the break of the silicone sealing ring. Each original data and product often has its own load, and silicone sealing ring is not included. For example, the rated load that silicone sealing ring can resist is 10N, while the natural environment at work will have 20N. Under such overload conditions, it is very simple to break. Therefore, when designing sealing ring products, it is necessary to check the relevant data to see how much the load of the product is, whether the product is in overload operation, generally not more than 90% of the product load is relatively good. The root cause of damage to the silicone seal ring. Embrittlement of raw materials of silicone sealing ring: in many cases, embrittlement of raw materials is also the key reason for rupture. each material often has its own service life. if embrittlement exceeds its own service life for a long time, it will break. if embrittlement occurs, the product will become hard and brittle, and then stress will occur on the vacancy to cause rupture. therefore, silicone sealing ring on mechanical equipment products needs to be embrittled and replaced immediately before rupture, prevent production accidents due to rubber ring rupture. 1) The color requirement of the general sealing ring is the customer's requirement. It is mainly required to distinguish from other sealing rings or to keep the color consistent with the supporting parts. It has nothing to do with the function. 2.) It has no effect on the function. Generally, silica gel is natural color, that is, semi-transparent color, and there are also transparent color. Color matching will not affect the function of silica gel itself. The main reason is that the composition of color paste is also silica gel, and the proportion added to the silica gel of the sealing ring produced by us is very small, with little fluctuation on the function.

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How to deal with the aging phenomenon of silicone sealing ring

How to deal with the aging phenomenon of silicone sealing ring

2021-06-19 17:02:40

The prevention of aging phenomenon focuses on the correct selection of silicone keys and formula design, plus rigorous production concepts, so as to increase the life of silicone products and play their due special functions. Silicone sealing ring surface treatment, experience shows that the cylinder piston and piston rod surface characteristics of the seal life has a very large impact. When selecting O-ring specifications, the material of O-ring must be determined first. At present, in industrial parts, the material of O-ring in life is NBR nitrile rubber. The compression of the O-ring is generally mainly determined by the hardness and material of the O-ring. If the hardness of the O-ring is 70 degrees, the compression of the O-ring is equal to 20%. Silicone waterproof ring is generally installed in several places, grooves, planes, and convex grooves. The installation method of each product is different. Its stress process will also affect the service life and function of the product. Silicone waterproof ring hardness and softness influence: many times according to the different softness of silicone products can completely change the functionality and structure of the product, so the silicone sealing ring in the use process due to the choice of different hardness after stress, stretching, extrusion and other phenomena, the sealing ring will appear some unavoidable problems. The environmental conditions of the finished silica gel products, over time, cause cracking or hardening, silica gel physical degradation and other phenomena, called aging phenomenon, the cause of aging, there are external factors and internal factors:. 1. External factors: external factors such as oxygen, oxide, ozone, heat, light, radiation, mechanical fatigue, lack of processing, etc. 2. Internal factors: Internal factors include the type of silica gel, the way of molding, the degree of bonding, the type of matching drugs, factors in processing engineering, etc.

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