In the sealing parts of rotary joints, I believe that many people have difficulty distinguishing between mechanical seals and ordinary seals, and even always think that they are the same kind of sealing parts. In fact, this is not the case. Today, the manufacturer of rotary joints, Daweiruisi, will talk about it. What is the difference between them?

1. The difference between rotary joint mechanical seal and ordinary seal

1) The mechanical seal of the rotary joint is one of the basic mechanical components with a precise and complex structure. It is the key component of various pumps, reaction synthesis kettles, turbo compressors, submersible motors, and other equipment. The service life of rotary joint mechanical seals depends on many factors, such as shape, the accuracy of the machine, correct installation and use, etc.

2) The hydraulic seal of the rotary joint has pressure requirements, and the joint surface is required to have a certain smoothness. The sealing element of the rotary joint is mostly made of rubber, and the sealing effect is achieved through the local deformation of the seal.

The following article also introduces the sealing of rotary joints. Interested partners can click to read:

Problems with rotary joint seals and causes for these problems

In classification:

Rotary joint mechanical seal model: centralized seal series, light mechanical seal series, heavy mechanical seal series, etc.

Hydraulic seals: Rotary joint lip seals, V-seals, U-seals, Y-seals, YX-seals, and commonly used combined seals for hydraulic cylinders, mainly Bud rings, Gree rings and Sterling rings Special seal.

On shopping:

When purchasing and repairing rotary joint seals, most users will buy according to the size and color of the sample, which will only increase the difficulty of purchasing, and may not be able to select the right product. It is recommended to use the following procedures to improve the accuracy of purchasing seals sex:

1. Movement direction: first determine the movement direction of the location of the seal, such as reciprocating, rotating, spiral or fixed

2. Key points of sealing: for example, determine whether the active point is the tie rod seal on the inner diameter or the active point is the piston seal on the outer diameter, etc.

3. Temperature grade: refer to the original machine operating instructions or evaluate the working temperature according to the actual working environment to determine the required materials.

2. Performance requirements for corrosion-resistant rotary joints

In the corrosive medium, the parts of the mechanical seal of the rotary joint will be corroded by the acid or alkali of the medium, and the friction surface will also be subjected to wear and various corrosion at the same time, which can be called "abrasion", and the corrosion rate is no friction. 20~50 times.

Some sealing structure materials have excellent corrosion resistance, but the wear resistance is relatively poor; while some sealing structure materials have good wear resistance, but the corrosion resistance is very poor.

Therefore, the sealing friction pair must be both corrosion-resistant and performance-resistant, and the auxiliary sealing ring, elastic element (spring, bellows compensator) and other structural accessories must also have good corrosion-resistant performance.

3. Corrosion-resistant rotary joint mechanical seal design

When designing a corrosion-resistant rotary joint mechanical seal, the following measures are generally taken:

1) Isolation measures for rotary joint sealing structure

The rotary joint of the external structure can be used, and the external seal can make no metal parts come into contact with the fluid medium, and small parts such as springs, bellows compensators, pins, etc. can not be corroded by the fluid medium. The external sealing structure has external compression spring sealing structure and

There are two types of bellows compensation sealing structure, the bellows compensation sealing structure is better than the above one. If the corrosion resistance of the material of the rotary joint seal assembly allows, the built-in seal structure can also be used.

2) Select the rotary joint material with good corrosion resistance

It is made of metal materials with better corrosion resistance, such as stainless steel rotary joints. The sealing component can choose the sealing material of PTFE or other materials according to the chemical properties of the medium. Also, pay attention to whether the material used in the rotary joint has a chemical reaction with the circulating medium.

Avoid all kinds of risks.

3) Rotary joints need to take measures to collect leakage liquid and gas

In order to ensure the safety of production and the responsibility of personnel in the production process, the rotary joint should be provided with a leakage port to ensure that the corrosive or toxic medium leaked when the tank leaks can be effectively collected, safely discharged, or discharged after treatment.

Well, the above is the whole content of the rotary joint that Daweiruisi brought to you today. I believe that through this article, everyone can distinguish the mechanical seal and the ordinary seal of the rotary joint. At the same time, you should have some understanding of the mechanical seal design requirements of the rotary joint. , I hope the above content is helpful to you. For more information on rotary joints, please click below: Rotary joint form selection and selection steps