There are many factors affecting the forged valve seal, mainly as follows:
Under the action of temperature or sealing force, the structure of the sealing surface will be changed. And this change will affect and change the mutual forces between the sealing surfaces, which leads to reducing the sealing performance of the forged valve.
Therefore, in the choice of valve seals, we must choose the elastic deformation of seals. Also importantly, we should pay attention to the width of the sealing surface. The reason is that if the contact surface of the sealing surface is not completely consistent, when the width of the sealing surface increases, it is necessary to increase the force required for sealing.
Specific Pressure of Sealing Surface
The specific pressure of the sealing surface also affects the sealing performance and service life of the forged valve. Therefore, the specific pressure of sealing surface is also a very important factor. Under the same conditions, too much specific pressure will cause damage to the forged valve, but too little specific pressure will cause leakage of the forged valve. Therefore, we need to fully take into account the design of the appropriate pressure.
The Physical Properties of Medium
The physical properties of the medium also affect the forged valve sealing performance. These physical properties include temperature, viscosity, and surface hydrophilicity. Temperature change not only affects the relaxation degree of sealing surface and the change of part size, but also has a close relationship with the viscosity of gas.
The viscosity of gas is increasing or decreasing with the increase or decrease of the temperature.
Therefore, in order to reduce influence of the temperature on the sealing performance of the forged valve, we attach importance to the design of the elastic valve seat and other thermal compensation of the forged valve in the design of the sealing surface. Medium viscosity is related to the permeability of the fluid.
Under the same conditions, the greater the viscosity is, the smaller the permeability of the fluid is. Hydrophilic surface refers to the metal surface in a layer of a film, in order to remove the film. This thin film of oil damages the hydrophilic properties of the surface and blocks the flow path.
Quality of Sealing Face
The quality of sealing face mainly means that we should check the material selection, matching and manufacturing accuracy. For example, the disc fits well with the seat sealing surface to improve tightness. The characteristic of more circular waviness is its good labyrinth sealing performance.
Forged valve leakage is common in life and production. Lightly, leakage can cause waste, such as tap water forged valve leak. Seriously, it could bring life-threatening and serious consequences, such as chemical industry of poisonous and harmful, inflammable, explosive and corrosive medium leakage in the chemical industry, becoming serious threats to personal safety and property safety, or causing environmental pollution accidents.
A rotating drive by external force to open and close the forged valve are designed to have a sealing device, which is used in the stuffing box installed with a certain number of packing ring, and even to achieve the sealing effect, but how is the sealing performance?
Forged valve packing leakage is one of the most vulnerable parts of the forged valve leakage fault, but there are two reasons.