锦州What are the principles and installation steps of API682 mechanical seal?

What are the principles and installation steps of API682 mechanical seal?

Principles and installation steps of API682 mechanical seal

1、 API682 Mechanical Seal Principle

API682 mechanical seal is a shaft seal device used for rotating equipment such as pumps, compressors, etc. Its main purpose is to prevent the leakage of liquid or gas being transported from the gap between the rotating shaft and the stationary shell.

Sealing interface principle: Mechanical seals are mainly composed of static rings and dynamic rings. The moving ring rotates along with the shaft, while the stationary ring is fixed on the sealing chamber. During normal operation, the end faces of the moving and stationary rings are tightly fitted, forming a narrow sealing end face. When the shaft rotates, relative motion occurs between the moving ring and the stationary ring, forming a very thin liquid film on this sealing end face (for liquid media). This liquid film serves a dual purpose of lubrication and sealing, reducing friction and wear while preventing medium leakage. The formation of liquid film is the result of multiple factors such as the pressure of the medium itself, the structural design of the sealing element, and the fluid dynamics generated by rotation.

Auxiliary sealing principle: In addition to the sealing end face, there are also auxiliary sealing components such as O-rings, rubber bellows, etc. These auxiliary sealing components are mainly used to prevent medium leakage between the stationary ring and the sealing chamber, as well as between the moving ring and the shaft. They fill gaps through elastic deformation and provide effective sealing at static sealing locations. For example, the O-ring will be compressed after installation, generating a certain elastic recovery force, making it tightly adhere to the sealing groove and the surface of the mating components, thereby preventing the leakage of the medium.

2、 Installation steps for API682 mechanical seal

preparation

Check component integrity: Before installation, it is necessary to carefully inspect all components of the mechanical seal, including the moving ring, stationary ring, seals, springs, etc. Ensure that the components are not damaged, scratched, or have any other defects. At the same time, check whether the model and specifications of the components match the equipment requirements.

Cleaning work: Thoroughly clean the sealing chamber, shaft, and all surfaces of the components to be sealed. Clean the surface of oil stains, rust, impurities, etc. to prevent these pollutants from entering the sealing surface and affecting the sealing performance. Suitable cleaning agents and tools such as sandpaper, cloth, etc. can be used for cleaning.

Tool preparation: Prepare the necessary tools for installation, such as wrenches, screwdrivers, specialized fixtures, etc. Ensure the accuracy and applicability of the tool to avoid damage to the sealing components during installation.

Install the static ring

Place the static ring in the corresponding position of the sealing chamber, paying attention to the correct installation direction of the static ring. Some static rings may have positioning slots or markings and need to be installed in the specified direction. Then use a suitable tool to gently press the stationary ring into place, ensuring a tight and even fit between the stationary ring and the sealing chamber.

Install the dynamic ring and accessory components

Installing the dynamic ring on the shaft usually involves the use of some sealing components, such as O-rings. When installing the dynamic ring, be careful to avoid damaging the sealing surface and sealing components. For mechanical seals with springs, install the spring on the moving ring or corresponding support component, adjust the pre tension of the spring to meet the equipment requirements. The magnitude of the preload force will affect the contact pressure of the sealing end face, thereby affecting the sealing performance.

Adjustment and inspection

After installation, manually rotate the shaft and check for any jamming between the moving and stationary rings. Ensure that the sealing end face can move relatively smoothly. At the same time, check if there are any signs of leakage in the auxiliary sealing area, and if there are any problems, adjust and repair them in a timely manner.

Conduct trial operation

After completing the installation and preliminary inspection, conduct a trial operation of the equipment. During the trial operation, closely observe whether there are any abnormal situations such as leakage or heating in the sealing area. If the leakage exceeds the specified standard or there is abnormal heating, it is necessary to immediately stop the machine for inspection, identify the cause, and take corresponding measures.

Proper installation and understanding of sealing principles are crucial for the effective operation and longevity of API682 mechanical seals, ensuring the safety of the equipment.