Precautions for Installing Sealing Rings on Spindles

We have compiled detailed steps and precautions for installing sealing rings on rotating spindles. The installation process requires meticulous execution to ensure sealing effectiveness and spindle operational precision.
Pre-installation Preparation: Before commencing installation, ensure the following preparations are completed:
1. Inspect the sealing ring: Verify the sealing ring is clean, undamaged, and free from defects such as scratches or cracks.
2. Clean installation surfaces: Thoroughly clean all contact surfaces (spindle, bearing housing, etc.), removing oil residues, contaminants, and burrs.
3. Prepare lubricant: Select appropriate grease or oil based on seal type. For lip seals, apply clean lubricant to the sealing lip. For O-rings, grease application facilitates installation.
 
Detailed Installation Procedure
The core steps for installing rotating spindle seals are as follows:
1. Seal Installation
Lip seals (oil seals): Ensure the lip faces the sealed medium (pressure oil) during installation. Press the seal into position using specialised tools or applying uniform force. Avoid direct hammering or chiselling to prevent lip damage.
O-ring Seals: Ensure adequate pre-compression during installation (typically 3%-8% for rotating seals). Avoid excessive stretching or twisting. Use guide sleeves when passing through sharp edges such as threads or keyways.
Mechanical seals (driving the stationary ring): First install the rotating ring and stationary ring onto their respective components. Apply preload to the rotating rings via springs to ensure tight contact between the rotating ring and the housing end face. During assembly, ensure the rotating and stationary rings are aligned. Finally, bolt the base and end cover securely.
2. Ensuring Installation Accuracy
Post-installation, verify the radial runout and face runout of the main shaft, confirming that coaxiality and perpendicularity meet specifications (e.g., radial runout ≤ 0.005 mm, face runout ≤ 0.003 mm). Should accuracy fall short, adjust the bearing housing position or grind the contact surfaces.
3. Sealing and Lubrication
When installing the seal ring, apply a small amount of grease to the sealing lip to prevent scratching the sealing surface during assembly. Fill with lubricating grease according to design specifications, ensuring moderate quantity—excessive amounts may cause overheating, while insufficient amounts lead to inadequate lubrication.
4. Critical Precautions
Installation Orientation: For Y-type, U-type, and similar seal rings, the lip edge must face the pressure direction of the sealed medium.
Avoid Old Contact Traces: When replacing seals, the new lip must not overlap the old contact area on the shaft. Position it closer to the sealed fluid side.
Use Specialised Tools: For difficult installations, employ specialised tools to gradually press the seal into place. Avoid forceful or improper handling.
 
Post-Installation Inspection
Upon completion, conduct the following checks to ensure quality:
Seal Integrity Test: Verify the seal is fully seated without misalignment or looseness, ensuring no leakage.
Operational Test: Rotate the spindle to detect any abnormal noise or vibration, verifying assembly quality.
 
We trust this information assists you in successfully installing the rotating spindle seal. Should you require further guidance on specific seal types (e.g., mechanical seals, lip seals), please do not hesitate to contact us.