If you work with applications that require a gasket, four words you never want to hear are: “We’ve got a leak”. (We know there are others, but we’ll just focus on gaskets since that’s what we can help with.) There are a lot of factors that can contribute to a leak, and getting to the root cause can sometimes be a difficult task.
Today, we’re going to take a deep dive into some of the potential causes of your fluid leak. As you’ll see, you can’t always just blame your gasket. Below are a few reasons why your joint may be leaking fluid, and what you can do about it.
Why Am I Leaking Fluids?
1. Is your gasket material compatible with the fluid you’re sealing?
Not all materials are created equal when it comes to sealing fluids. Some gasket materials are designed to “swell”, creating a better seal when coming in contact with fluids and oils. However, some fluids can actually disintegrate improperly chosen gasket materials. Be sure you understand the interaction between what you are sealing and the gasket material.
2. You might have a design problem.
You’ll want to do your homework with this one. Design problems can be a big issue. Is your joint loaded sufficiently, and is the load distributed properly and evenly? Do you see any flange distortion? What is the finish and the flatness of the flange? Unless you can find a gasket material that can compensate for the design issues, you’ll be back to square one. If this is the case, be sure to investigate all of your material options before entering into a redesign. There are materials out there that can compensate for a lot of design issues, so be sure to talk to a gasket material expert to help you find the right solution.
3. What is your internal pressure?
If there is too much pressure for the material chosen, a change may need to be made. High pressure can force leaks. A gasket design may require reinforcement with a metal core or from a flange ring to contain the pressure.
4. Is your material rated for the temperatures in your application?
If your material is burning or oxidizing away, take a look at your temperatures. A lot of times, internal temperatures can very easily exceed what was intended in the design phase once you start testing. You may need to get your hands on a higher temp-rated material.
5. You might have expansion/contraction issues.
Does it look like thermal expansion is tearing your gasket apart and causing a leak? If so, can you add a coating to provide lubricity? This would allow the surface to “slip”, thus accommodating this effect. If not, you may need to look at more robust materials.
6. None of the above.
If the issue is still a mystery, look at the history of similar applications to see if there is anything obvious that stands out as a factor. Historical comparisons can sometimes be a helpful troubleshooting method.
Stopping the Leak
Dealing with unexpected results can be incredibly frustrating, and with a fluid leak, it is very easy to just assume the gasket is the issue and start testing various materials just to find a solution. Taking the time to really understand the underlying causes of your problem will help you make a much more educated decision. Once you start to understand why your joint is leaking, talk to your trusted gasket material supplier. They should be able to suggest a material that will better fit the requirements of your application.
Until next time!