Mechanical Seals vs. Packing: Which is Superior?
As it becomes required and more important to keep manufacturing eco-friendly, the debate between traditional packing versus mechanical seals has become clear. While packing has lower upfront costs, over time it becomes much more expensive as the material requires continual maintenance and replacement. Packing is also more prone to leaking and product loss.
There’s no way around it, pumps need to be sealed. Over time a leaking system can be costly, inefficient, and detrimental to the environment, so it’s imperative to choose the right long-term solution.
How Packing Works
Packing is a relatively simple process. A soft material is stuffed into the gap between the pump and the shaft, preventing most leakage. There are a wide variety of materials used depending on the kind of material being pumped. It’s simple and easy to maintain, which is an advantage for packing.
Disadvantages of Packing
The primary downside of packing is that there is inevitable leakage, which causes a range of issues. The first issue is that leaking fluid can be a working hazard, causing slips and falls and their inevitable workers compensation cases. Many fluids aren’t allowed any visible leakage at all due to the fact they are corrosive, toxic, flammable, or dangerous to the environment. Packing can also cause wear and tear on the machinery they are sealing, causing the machines themselves to require repair or replacement.
Finally, while packing may be cheaper up front, they do lose product due to the leakage, costing money. So, while you may want to start out using packing as a cheaper start-up cost, eventually the packing will become more expensive. Plus, the regular maintenance requirements will eat up time as well, which is yet another cost.
How Mechanical Seals Work
Mechanical seals come in a variety of shapes and sizes, due to the specific nature of their designs and the systems they are used in. Some can be simple, while others are more complex, requiring multiple fail-safes and self-correcting features.
Most basic mechanical seals have three sealing points. The first portion is sealed to the stationary part of the pump with an O-ring. One portion of the seal is generally spring loaded in order to compensate for any minor staff deflection.
Perhaps the most important and complex part of the seal is the middle portion where the rotating and stationary portions meet. This section must be lubricated enough to rotate, but tight enough not to allow any leakage. Both the force of the fluid and the design of the seal contribute to pushing the seal faces together. These surfaces are microscopically flat, ensuring a tight seal so that fluid cannot escape and contaminants won’t enter or damage the seal.
Advantages of Mechanical Seals
Over time, mechanical seals will save you money through a variety of means. Mechanical seals that are correctly chosen, operated, and installed won’t do much damage to the systems they are attached to. They save time as they require little upkeep and maintenance in comparison to packing. Preventing virtually all leakage will prevent money lost through the steady leakage of packing. Mechanical seals also consume less power.
There are disadvantages to mechanical seals, such as a higher initial cost. Mechanical seals are also more difficult to maintain, requiring a higher level of expertise. Most of the disadvantages can be remedied by design decisions, such as creating a secondary seal in case of a failure in the first seal.
Your Needs
No matter your manufacturing needs, Real Seal can provide you with quality solutions for any operation. Contact Real Seal for all of your sealing needs.
