Carbon graphite seals have become vastly preferred across industries because they’re critical for compressors, pumps, and other rotating machinery. They possess incredible properties that make them ideal for applications where leak prevention and seamless operation are crucial.
However, these robust seals can still fail, and understanding the causes is crucial to optimize their performance. Let’s discuss the problems of graphite seals and tips for maintaining them.
Common Issues With Graphite Seals
While these seals offer numerous advantages, several factors can contribute to their premature failure. Here are the problems often associated with them:
- Material Mismatch
One primary cause of seal failure is choosing the wrong grade of graphite for the application. Carbon graphite comes in different grades, each with varying strength, hardness, chemical resistance levels, fluid properties, temperature limitation, and pressure thresholds. Using a grade incompatible with the environment in which it operates can result in rapid seal degradation.
- Poor Installation
Graphite seals can only perform well if installed correctly. Misalignment and minor errors when mounting the seal can cause leaks, uneven load distribution, severe seal and equipment damage, and premature failure.
- Shaft Misalignment
Skewed alignment between the rotating shaft and stationary housing leads to uneven loading on graphite seals. Neglecting this issue speeds up seal face degradation, increasing the likeliness of leakage.
- Vibration Levels
Factors like loose or worn bearings, warped shafts, and misalignment between the pump and drive can increase vibration in equipment. Prolonged exposure to excessive vibration induces more stress on the seal than it can handle, eventually causing cracking, chipping, and early wear and tear.
- Surging Pressure
The pressure a graphite seal can withstand depends on the material’s grade. If the pressure level within a machine system suddenly spikes or fluctuates, the seal will get overloaded and suffer distortion, cracking, or complete failure.
- Lubrication Neglect
Although these seals are self-lubricating, some applications require external lubrication for seamless operation. Inadequate lubrication causes excessive friction, which generates excessive heat, accelerates wear, and results in seal failure.
- Extreme Temperatures
Different grades of carbon graphite can only withstand specific temperature ranges. Using the seal under temperatures that the material grade can endure can wear and deform it over time, reducing its ability to control leaks.
- Chemical Degradation
Graphite seals are chemical resistant. However, exposing them to incompatible chemicals or substances with extreme pH levels can soften and crack them. Because of that, the seals become less durable and dysfunctional over time.
Maintenance Practices for Graphite Seals
Implementing proper upkeep and preventive strategies are necessary to ensure these seals’ functionality and extend their service life. Here are crucial aspects to keep in mind:
- Correct Installation
No matter how meticulous, following the proper installation procedure is necessary. The seal should be aligned correctly and fastened securely. It’s also best to have a professional or trained technician install seals to reduce the risk of errors.
- Proper Cleaning
Use non-corrosive cleaners to remove dirt and residue without damaging the seal surface. Refrain from using abrasive cleaning methods to avoid scratching and weakening the seal. Moreover, cleaning seals regularly ensures the end products are free of contaminants.
- Regular Inspection
Check the seals for signs of wear, damage, or leakage, and see if the rotating shaft and stationary housing are aligned correctly. Also, periodically analyze the contained fluid for contamination, degradation, or particles that can compromise the seal’s structure and performance.
- Lubrication Checks
For applications requiring external lubrication, use a lubricant suitable for carbon graphite and apply the right amount at the recommended intervals. Avoid dry operation whenever possible to prevent overheating and accelerated material wear.
- Vibration Monitoring
Consider implementing a system for monitoring vibration. Technicians can use it easily detect irregularities and ensure that the seals operate under vibration levels that the carbon graphite grade can handle.
- Equipment Technician Training
Establish quality and regular training in seal installation and maintenance for your personnel so that they follow guidelines diligently and spot potential issues early. Having well-trained technicians on deck can give you the confidence that your machines are in good hands.
Don’t Wait for Carbon Graphite Seals for Fail
Understanding the contributors to seal failure, detecting potential issues early on, and performing proper upkeep extend graphite seals’ lifespan. Working closely with experienced engineers and manufacturers is also essential to ensure the seals remain effective throughout their lifecycle. By following these tips, you can optimize the performance of these valuable assets and keep your operations running smoothly.