Valve leakage is very common in daily life and industrial production, and the impact is very large. At least, it will cause waste or bring danger to life. For example, tap water valve leakage will lead to serious consequences, such as toxic, harmful, flammable, explosive and corrosive dielectric leakage in the chemical industry, which will seriously threaten personal safety, property safety and environmental pollution. A valve that relies on external force to rotate to open and close is designed with a sealing device, which is used to install a certain number of packing sealing rings in the packing culvert, so as to achieve the sealing effect. But what is the sealing condition? The leakage at the packing of the valve is one of the parts of the valve that are prone to leakage failure, but the reasons are mainly caused by the following aspects.

1、密封副结构

1. Sealing auxiliary structure

在温度或密封力作用的变化下，密封副的结构就会发生变化。而且这种变化会影响和改变密封副相互之间的作用力，从而使阀门密封的性能减小。因此，在选择密封件时，一定要选择具有弹性变形的密封件。同时，也要注意密封面的宽度。原因在于密封副的接触面不能完全吻合，当密封面宽度增加，就要加大密封所需要的作用力。

Under the change of temperature or sealing force, the structure of the sealing pair will change. And this change will affect and change the force between the sealing pairs, thus reducing the performance of the valve seal. Therefore, when selecting seals, be sure to select seals with elastic deformation. At the same time, pay attention to the width of the sealing surface. The reason is that the contact surface of the sealing pair cannot be completely matched. When the width of the sealing surface increases, the force required for sealing shall be increased.

2、密封面比压

2. Specific pressure of sealing surface

密封面的比压大小影响着阀门密封性能大小和阀门的使用寿命。因此，密封面比压也是非常重要的一个因素。在相同的条件下，比压太大会引起阀门的损坏，但比压太小酒会造成阀门泄漏。因此，需要我们在设要充分考虑到比压的合适度。

The specific pressure of the sealing surface affects the sealing performance of the valve and the service life of the valve. Therefore, the specific pressure of the sealing surface is also a very important factor. Under the same conditions, the valve will be damaged if the specific pressure is too high, but the valve will leak if the specific pressure is too low. Therefore, we need to fully consider the suitability of specific pressure in the design.

3、介质的物理性质

3. Physical properties of media

介质的物理性质也影响到阀门密封性能。这些物理性质包括温度，粘度和表面的亲水性等。温度变化不仅影响着密封副的松弛度和零件尺寸的改变，还与气体的粘度有着密不可分的关系。气体粘度随着温度的升高或降低而增大或减小。因此，为了减少温度对阀门密封性能的影响程度，我们在进行密封副设，要把其设计成弹性阀座等具有热补偿性的阀门。粘度与流体的渗透能力有关。当在相同条件下时，粘度越大，流体的渗透能力就越小。表面的亲水性是指在金属表面有一层薄膜时，要去掉这层薄膜。因为这层很薄的油膜，会破坏表面的亲水性，导致堵塞流体的通道。

The physical properties of the medium also affect the sealing performance of the valve. These physical properties include temperature, viscosity and surface hydrophilicity. The change of temperature not only affects the relaxation of sealing pair and the change of part size, but also has an inseparable relationship with the viscosity of gas. The gas viscosity increases or decreases with the increase or decrease of temperature. Therefore, in order to reduce the influence of temperature on the sealing performance of the valve, when we design the sealing pair, we should design it as a valve with thermal compensation, such as an elastic valve seat. Viscosity is related to the permeability of the fluid. Under the same conditions, the greater the viscosity, the smaller the permeability of the fluid. The hydrophilicity of the surface refers to the removal of a thin film on the metal surface. Because this thin oil film will destroy the hydrophilicity of the surface and block the channel of the fluid.

4、密封副的质量

4. Quality of sealing pair

密封副质量主要是指我们要对材料的选择，匹配，制造精度上进行把关。比如，阀瓣与阀座密封面很吻合，能提高密封性。环向波纹度多的特点，是其迷宫密封性能好。

The quality of sealing pair mainly means that we should check the selection, matching and manufacturing accuracy of materials. For example, the sealing surface of valve clack and valve seat is very consistent, which can improve the sealing performance. Its labyrinth sealing performance is good because of its many circumferential waviness.

以上就是良工阀门为大家介绍的内容，感谢您在百忙之中查看我公司的信息内容，如果您想要了解的更多，欢迎您来电进行咨询!http://www.jnlgvf.com

The above is what Lianggong valve introduced to you. Thank you for checking the information of our company in your busy schedule. If you want to know more, you are welcome to call us for consultation! http://www.jnlgvf.com