reducing tee factory

If the method of washing with distilled water is used, the content of chlorides can be reduced. However, this method is difficult to implement and cannot be generalized. Ester is suitable for special needs. In order to protect the valve stem and prevent the corrosion of asbestos packing, the asbestos packing is filled with corrosion inhibitor and sacrificial metal.

The corrosion inhibitor consists of sodium nitrite and sodium chromate, which can form a passivation film on the surface of the valve stem to improve the corrosion resistance of the valve stem; the solvent can make the corrosion inhibitor slowly dissolve, and can play a lubricating effect; in asbestos Zinc powder is added as a sacrificial metal.

In fact, zinc is also a corrosion inhibitor. It can first combine with the chloride in asbestos to greatly reduce the chance of chloride contact with the valve stem metal, thereby achieving the purpose of anti-corrosion. If corrosion inhibitors such as red lead and calcium lead acid are added to the paint, spraying on the surface of the valve can prevent atmospheric corrosion. 5. Electrochemical protection There are two types of electrochemical protection: anode protection and cathodic protection.

The reducing tee factory anode protection is to use the protective metal as the anode to introduce an external direct current to increase the anode potential in the positive direction. When it increases to a certain value, a dense protective film is formed on the surface of the metal anode, which is the passivation film. The corrosion of the metal cathode is drastically reduced. Anodic protection is suitable for metals that are easily passivated. The so-called cathodic protection is to use the protected metal as the cathode, and apply a direct current to reduce its potential in the negative direction. 

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Clamp Saddle factory

If the centrifugal cryogenic Clamp Saddle factory produces noise and vibration during operation, and is accompanied by a decrease in flow, head and efficiency, sometimes it can not even work, and during maintenance, it is often found that there are pitting or honeycomb damage near the inlet edge of the blade. In severe cases, the entire blade has this phenomenon, and even the blade is penetrated, which is the damage caused by cavitation.　　

The cause of cavitation in the centrifugal cryopump: the pump does work on the liquid through the rotating impeller, which increases the energy of the liquid. During the interaction, the velocity and pressure of the liquid change. Usually, the inlet of the centrifugal cryopump impeller is the place with the lowest pressure. If the pressure in this place is equal to or lower than the vaporization pressure of the liquid at that temperature, there will be a large amount of steam and gas dissolved in the liquid escaping from the liquid, forming many small bubbles of steam and gas mixed.

When these small bubbles flow with the liquid to the high-pressure zone, the vaporization pressure inside the bubble is greater than the vaporization pressure around the bubble, resulting in a pressure difference. Under the action of this pressure difference, the bubble bursts under pressure and condenses again. During the condensation process, the liquid particles accelerate from the surroundings to the center of the bubble. At the moment of condensation,

the particles collide with each other, generating high local pressure. If these bubbles burst and condense near the metal surface, the liquid particles will continue to hit the metal surface like countless small warheads. Under high-pressure and high-frequency continuous blows, the metal surface is gradually damaged due to fatigue. This damage is usually called denudation. Some active gases (such as oxygen, etc.) are also mixed in the generated bubbles, and the heat released when the bubbles are condensed can chemically corrode the metal. 

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