Pumps are devices that move liquids or gasses by mechanical action. For the pump to work, it needs to be sealed completely tight to avoid leaks from occurring. In the past, pumps were sealed using rings, however rings were not effective in protecting the device from leaks. Today, most pumps are sealed by mechanical pump seals that are more competent in preventing leaks from happening.
Benefits of Seals
Leaking is the primary issue that is addressed by seals. The most obvious benefit of seals is that they allow pumps to function leak-free. So, if you are still using packing seals, then it is time that you switched to mechanical seals. Below are the benefits of mechanical pump seals.
• Having less fluid loss in a machine means better savings in terms of repair work due to pump failures. Moreover, they reduce the number of hazards that can put the lives of the pump operators in danger. Less leakage means fewer incidents of falling and slips due to the wet floor. It also reduces the potential of harmful emission, if the pump is housing toxic chemicals.
• Pumps do still have leaks, just not visible leaks. Experts approximate “healthy” and acceptable leaks to half of a teaspoon a day under normal operating procedures. Most machines will recapture the lost air and condense it.
• Seals can adjust to different faces of wear as they come with inboard springs. This reduces the necessary daily maintenance that needs to be done for the seal to work optimally.
Elements of A Seal
Seals allow the pumps to work by reducing downtime caused by leaks. They are commonly applied to contain any liquid or gas within a vessel where there are rotating shaft and a stationary housing. But how do seals protect the pump? Simple, they comprised of elements that would protect the machine against leaking. Below are the elements of mechanical seals.
• A set of primary sealing faces: A mechanical seal is made up of a set of lapped faces to minimize leaking. Different faces are made from different materials such as carbon-graphite and ceramic to prevent them from adhering to one another. Different materials are made so that they can perform different functions. For instance, one face of the housing is held stationary while the other one rotates along with the shaft.
• Static seals: Mechanical pump seals also come with a set of static seals like V-rings or O-rings to provide secondary protection against leaks.
• Spring: To create face contact, seals often come with a spring member which include either single or multiple springs.
• Other hardware: Seals are also made from other hardware which include gland rings, shaft sleeves, compression rings, pins, and collars.
Things to Consider When Looking for Seals
There are different mechanical pump seals out there on the market, but before you decide on which one to get, there are three important things that you need to remember when looking for mechanical seals.
• Seal faces need to stay together. If they open, leaks will occur thus allowing solids or contaminants to enter between the faces. Entry of contaminants will likely destroy the lapped surfaces not only of the seal but also the pump.
• The seal materials should be compatible with any fluids that are being pumped through the system. These include cleaners, solvent, and steam. Using fluids that are not compatible may destroy the seal by disintegrating its components and cause leaking in the pump.
• Mechanical seals have a good seal life. They expire once the carbon face is worn out which usually happens after a long time.
How Seals in Pumps Work?
Mechanical seals are watertight fittings that are located between the fixed part of a rotating device and a shaft thus they are commonly used in pumps. It is important to stress the water-tightness of the pump. This is achieved using a fine fluid or film that is located between two friction faces to prevent the remaining fluid from passing. The film also works as a lubricant thereby reducing the wear and tear between the two lapped faces. With a mechanical seal, the pump can work naturally without the fear of any leaks.
Seals provide damage-free and leak-free performance for almost any solution. Thus, understanding the science behind it will allow you to optimize the use of the seal based on its design.
For additional information and resources regarding the families of rubber and plastic sealants, machinery, and laboratory testing, contact Real Seal today.
