Hermetic connectors have become an industry standard when it comes to sealing equipment used in extreme conditions.
Submarines and orbiting satellites use this to keep them airtight, allowing them to operate in adverse conditions. They are also used to provide resistance to moisture ingress and withstand underground pressure.
As a matter of fact, this type of connector sealing was initially created for military electronic applications.
These days, hermetic seal connectors have been adopted for commercial and industrial use too. From oil rigs to mining equipment, and right down to medical equipment as well.
The significance of a successful connector cannot be further stressed, whether it’s for a fiber optic seal or a high-pressure hermetic seal. The following are 5 criteria that can help you achieve the required sealing for your operation.
1. Know the Levels of Hermetic Sealing
There is deep scientific complexity involved in sealing. Mechanical design, surface science, and fluid behavior, as well as materials science, contribute to the success of hermetic sealing.
There is no single type of sealing as it largely depends on the operating conditions. Varying levels exist to adapt to conditions, both environmental and operational, where the equipment will be used. At the very least, installations should prevent dust and withstand water ingresses aside from being gas-tight.
The right level will always depend on the values of leak rates. Leakage rates below 10-6 mbar*l/s is what you should be aiming for.
Achieving this level of sealing, every crucial area of a hermetic connection should be protected by its own independent seal.
2. Understand What Causes Leak and Diffusion
A hermetic barrier is not an absolute solution. Leakage and diffusion are two of the major factors that can contribute to its failure.
Small cracks, imperfections, and even tiny defects can result in gas leakages. These conditions can be prevented with proper installation and maintenance.
On the other hand, diffusion is a natural-occurring process which means it can never be prevented and fully eliminated. Even if protected by a solid barrier, gas can still pass through because of pressure difference. However, this mostly occurs with barriers made of rubber and plastics.
3. Ensure that No Gas Is Trapped
Even if you have chosen a stable and strong connector, it will not perform well and may even break at the slightest leak if it’s not installed properly. No gas should be trapped between assembled components.
The contact surface between components should be properly prepared before mounting any hermetically sealed connector. In addition, make sure that the connector should be fitted with just the right amount of torque.
4. Select the Right Material
The material of the connector is very significant in preventing leaks and diffusion. The diffusion effect is directly correlated to the type of material used.
Desorption, also known as outgassing, is another phenomenon that you should also be aware of. Environmental conditions influence the occurrence of this situation, as well as the actual material of the connector.
Some connectors which are made of insulating plastics, for example, can absorb small amounts of water. These water molecules are released over time due to temperature and environmental changes.
Outgassing may not pose a problem if the area where the equipment will be used is not subject to these environmental conditions.
5. Choose the Best Hermetic Connector
Hermetic connectors are designed to withstand extremely harsh environmental conditions, preventing air, gas, and liquid ingress.
They are expected to be of the highest quality showing no detectable leakage and diffusion. Hermetically-sealed connectors should be able to ensure a very stable pressure differential between both sides of the assembly.
They should be military-grade even if used in commercial and industrial operations, able to withstand varying pressures and altitudes.
In addition, these connectors should be able to hold out against diverse and extreme temperature conditions.
Fortunately, there is a multitude of options available that you can choose depending on your needs. From explosion-proof seals to sealed fiber optics that run on the ocean floor, you’ll find one that suits your operational needs.
Parameters of a Good Hermetic Connector
Keeping these 5 crucial parameters in mind can help you eliminate assembly failure. Ensuring that your connectors can withstand harsh environments and conditions will significantly eliminate failure at this level. But because they are designed and manufactured to operate in extreme conditions, you’re free to focus on other parts of the assembly.