Correctly installing ceramic friction rings is a key step in ensuring the sealing and stable operation of ceramic vacuum filters. It is necessary to strictly follow the four principles of positioning, cleaning, alignment, and fastening to avoid air leakage, wear, or equipment vibration caused by improper installation.
The installation accuracy of ceramic friction rings (also known as misalignment discs) as dynamic sealing core components directly affects the stability of vacuum systems. If not installed properly, it can cause a decrease in vacuum degree and an increase in energy consumption, and in severe cases, it can lead to friction surface erosion and spindle damage. The following is a standard installation process based on industry standards and equipment manufacturer practices:
Pre-installation preparation
Power off, shut down, and release pressure
Ensure that the equipment is completely stopped, turn off the vacuum pump and power, release residual vacuum and pressure in the system, and prevent accidental start-up or airflow impact.
Clean the working surface
Use a dust-free cloth dipped in alcohol or water to thoroughly clean the contact surface of the distribution head, the spindle end face, and the sealing groove, remove oil stains, dust, and old sealing materials, and avoid impurities getting trapped and causing eccentric wear.
Check the status of new parts
Confirm that the new ceramic friction ring has no cracks, broken edges, or surface scratches, and measure whether the thickness and flatness meet the original factory standards (usually flatness ≤ 0.005mm).
Standard installation steps
Positioning installation benchmark
Rotate the spindle to align with the "zero position" mark, ensuring that the friction ring corresponds one-to-one with the ventilation holes of the distribution head to avoid misalignment and confusion in the vacuum partition.
Apply lubricant (optional)
Apply a thin layer of specialized silicon-based grease between the friction ring and the grinding piece (such as graphite disc) to reduce dry friction during initial operation and extend its lifespan. Caution: Do not use lubricants containing metal particles.
Smooth insertion and compression
Hold the ceramic ring horizontally with both hands and slowly push it in along the main axis, ensuring that it is perpendicular to the main axis without tilting. After being in place, use a dedicated pressure plate or locking nut to evenly apply force and fix it to avoid cracking caused by one-sided force.
Adjust the axial clearance
Use a feeler gauge to measure the axial clearance between the friction ring and the grinding piece, with a standard value of 0.4-1.0mm. A gap that is too small can cause overheating and locking, while a gap that is too large can result in seal failure.
Manual turning test
After installation, manually rotate the spindle slowly for 1-2 turns to check for any jamming, abnormal noise, or uneven resistance. Only after confirming smooth operation can the machine be powered on for testing.
Installation precautions
Do not strike: Ceramic materials have high brittleness, and direct tapping with metal tools is prohibited. Rubber hammers or hydraulic devices should be used to gently press in.
Group replacement: It is recommended to replace both the ceramic friction ring and the grinding parts (such as graphite discs) at the same time to avoid early wear caused by poor fit between new and old components.
Clean environment: The installation process should be carried out in a dust-free or low dust environment to prevent hard impurities such as sand particles and metal shavings from entering the sealing surface.
First run monitoring: closely observe the temperature and vibration of the sealing part for the first 30 minutes after starting up. The normal temperature rise should be less than 15 ℃ and there should be no abnormal noise.