Extend The Lifespan of Industrial Seals: How Can It Be Done?

Industrial seals are used at the interfaces between components to prevent leakage. There are several types of seals available, each with its own unique construction and usage. Many seals have a limited lifespan, and the shelf life majorly depends on how they are used and stored. In order to get the most out of your seal, it is important to know how to properly store it when not in use. If you don’t take proper care of your seals, they will deteriorate faster, leading to poor sealing performance. This post will tell you know about the most common problems that occur with poorly stored seals. You will also get to know about the factors to consider when storing your industrial seal.

Common Problems Associated with Industrial Seals

As mentioned earlier, industrial seals are critical components that are used to prevent unwanted leaks, along with protecting the internal environment of sensitive components of turbines, engines, among others. However, some seals fail due to improper handling and storage. These failures can be costly as the use of damaged seal can cause product damage as well as contamination inside static and dynamic interfaces.

Maintaining the shelf life of your industrial seals can be tricky. Most times, industrial users purchase seals in bulk and store them for later use. In case the storage is not proper, it will drastically affect the performance and shelf life when put for industrial seals for applications later. The following are a few simple tips for storing your seals in order to maintain their quality whilst preventing spoilage.

1. Excessive swell
2. Spiral failure
3. Weather or ozone cracking
4. Change in properties
5. Change in color
6. Cracking
7. Softening
8. Hardening

Tips on Industrial Seal Storage Before Installation

Maintaining the shelf life of your industrial seals can be tricky. Most times, industrial users purchase seals in bulk and store them for later use. In case the storage is not proper, it will drastically affect the performance and shelf life when put for industrial seals for applications later. The following are a few simple tips for storing your seals in order to maintain their quality whilst preventing spoilage.

•    Temperature: Ensure to store the seals that are not in use in the prescribed temperature range. Most times, the ideal temperature range shall be between 15°C and 25°C. Also, it is not recommended to store them near radiator, boiler or any heater, or in areas where they get direct exposure to sunlight.

•    Humidity: Set a proper storage area where your seals do not expose to moisture content. In case such instances occur, you may slowly warm the seal to 20°C or to ambient temperature before using for sealing purposes.
 
•     Cleaning: Suppose you are taking the seal after a long time of storage for applications, ensure to clean them gently before using. You are safe to do this with clean cloth and warm water; however, refrain from using sand paper or steel brush for cleaning purposes.

•    Ozone: Be informed that ozone deteriorates industrial seals. Hence, it must be protected from circulating air and stored away from electric motor, or mercury vapor lamps.Be informed that ozone deteriorates industrial seals. Hence, it must be protected from circulating air and stored away from electric motor, or mercury vapor lamps.

•    Light and Radiation: Ensure not to store

•    Contact with Chemicals and Metals: Your polymer seals must be safe from direct contact with oils, greases, different solvents, and other chemicals. Also, it is recommended to avoid direct contact with certain kids of metals like iron, copper and its alloys (brass), and manganese.

Ensure to store the seals that are not in use in the prescribed temperature range. Most times, the ideal temperature range shall be between 15°C and 25°C. Also, it is not recommended to store them near radiator, boiler or any heater, or in areas where they get direct exposure to sunlight.Set a proper storage area where your seals do not expose to moisture content. In case such instances occur, you may slowly warm the seal to 20°C or to ambient temperature before using for sealing purposes.Suppose you are taking the seal after a long time of storage for applications, ensure to clean them gently before using. You are safe to do this with clean cloth and warm water; however, refrain from using sand paper or steel brush for cleaning purposes.Be informed that ozone deteriorates industrial seals. Hence, it must be protected from circulating air and stored away from electric motor, or mercury vapor lamps.Be informed that ozone deteriorates industrial seals. Hence, it must be protected from circulating air and stored away from electric motor, or mercury vapor lamps.Ensure not to store industrial seals under direct light source with high UV radiation. It is always recommended to keep them inside packages that come with optimal UV protection and other radiation hazards.Your polymer seals must be safe from direct contact with oils, greases, different solvents, and other chemicals. Also, it is recommended to avoid direct contact with certain kids of metals like iron, copper and its alloys (brass), and manganese.

In addition to the aforementioned points, you must make sure that you are not storing the industrial seals for a long time than the prescribed storage time. Also, when you are taking the seals for installation after a long time of storage, it is highly recommended to check the condition thoroughly before installation. Most of the issues like softening, stickiness or discoloration and cracking can be detected with just visual inspection. Refrain from using such deformed seals as such seals usually cause failure to the entire system. In case if you would like to know more about the proper storage of industrial seals when not in use, you can check the same with the manufacturer you procure the seal from. Industry leading manufacturers like SSP Seals offer expert customer assistance, clear your doubts, and offer tips to augmenting the shelf life of the seals.

Oil Seal Function and Working Principle

The area between the sealing edge and the shaft is the most important. The sealing effect is obtained by preloading the sealing lip, making its inner diameter slightly smaller than the diameter of the shaft. The garter spring ensures constant mechanical pressure and maintains the radial force on the shaft and extends the sealing edge to the defined width. Sealing is guaranteed by the surface tension of the hydrodynamic oil film between the flattened area of the seal and the shaft. The oil thickness must be between 1 and 3 mm to avoid leakage. The meniscus acts as an interface between the outside air and the fluid. Any rupture of the meniscus will cause a leak. This can occur if the shaft contains scratches along the path of the joint. Oil Seal Applications

Perhaps the most famous O-ring failure in history is that of the Challenger space shuttle, which ended the lives of seven NASA astronauts in January 1986. In the shuttle’s right rocket booster, a seal failed at the aft field joint that led to the spacecraft exploding. It was later found that the O-ring didn’t have the capability to perform correctly at lower temperatures, so it failed to seal fully.

Investigators theorized that cold temperatures at launch time and frozen water within the rocket motor’s joints resulted in O-rings that didn’t return to their correct shapes before launch. This O-ring failure resulted in the joint along the right rocket booster failing as heated; combustible gases caused blow-by and erosion. The resulting domino effect led to the Challenger’s explosion 28 seconds after launch.

While O-ring failures don’t normally result in loss of life, their failure can often damage machinery and cause production delays. Knowing how to improve an O-ring seal will also make an application safer for everyone involved. For those dealing with machinery or equipment that relies on O-rings to operate properly, it’s important to understand what makes them seal so they won’t fail unexpectedly.

Why Seals Fail

Before learning how to make an O-ring seal better, it’s important to understand why seals fail in the first place. Generally, seals stop working because they fail or wear out. Often preventative maintenance programs that utilize regular inspections will prevent failures by replacing old seals before they completely wear out and fail. However, sometimes seals fail for reasons other than natural wear and tear.

The primary culprit for seal failure is human error emanating from using the wrong seal for the application, as is what evidently happened to the Challenger space shuttle. This is especially true for seals used to join components. That’s why it’s always important to use seals intended for use with a specific component. However, many other things can cause seal failure. Understanding the symptoms and what to look for can help those tasked with correcting such problems.

The more common types of seal failure, along with ways to fix or prevent them, include: 

Abrasion: Signs of abrasion include scrapes or loose particles on the surface of the seal. While this could result from high temperatures, poor surface finish, or a rough sealing surface, these also indicate abrasive particles. To fix or prevent:

• Lube seal internally
• Remove abrasive materials from production environment
• Use gland surface finish recommended by manufacturer

Chemical degradation: When material becomes discolored, blisters or cracks prior to a seal failure, it’s likely due to chemicals degrading the material. The seal’s physical properties may also be seen to degrade. To fix or prevent:

• Ensure the seal’s material is compatible with chemicals in the environment
• Utilize an O-ring made from an elastomer that’s resistant to these chemicals.

Contamination: Foreign material on the seal’s surface cross-section indicates some type of contamination. This may result from conditions within the facility or degradation due to a chemical reaction. To fix or prevent:

• Use the correct seal material

Excess compression: Signs include a compressed seal occurring within a mated surface area, though alternatively, this could result from an improperly cured elastomer within the installed equipment or high temperatures. To fix or prevent:

• Confirm compatibility with material
• Ensure the correct design is being used
• Use only elastomers for O-rings that set at lower compression

Extrusion: When a seal’s edges become ragged or tattered along the low-pressure side, this is a warning of imminent failure. Though eroded gland edges, excessive clearances, high pressures, low modulus, too much elasticity, wrongly sized seal,s or other reasons could be the cause, it’s usually due to extrusion. To fix or prevent:

• Minimize clearances and pressure
• Use seals with elastomers that feature a greater modulus
• Use standby O-rings made from polymers

Heat degradation: When a seal shows radial cracks or its surface material becomes shiny and softens, the seal’s elastomers are likely not compatible with the system’s thermal requirements. To fix or prevent:

• Assess whether the seal’s surface can be cooled
• Select elastomer with sufficient thermal stability for seal

Improper installation: Damage occurring due to improperly installing a seal, or using the wrong type or size, can lead to seal failure. Indications like cuts, gashes or nicks on seal parts are indicative of this issue. To fix or prevent:

• Certify modulus is correct
• Clean surfaces and components of residual material
• Ensure the seal has the proper gland design
• Make sure the seal fits
• Remove any sharp edges
• Use the correct elastomer

Over-compression: When the surface of a seal develops circumferential splits with compressed surfaces, or if it becomes completely flattened, it’s likely to fail. Though this could result from improper design, environmental chemicals, changes in thermal volume or the selected seal doesn’t have properties necessary to withstand the compression, the problem is likelier due to over-compression. To fix or prevent:

• Confirm seal is sufficiently durable
• Ensure seal’s material properties are compatible with production environment
• Make certain seal meets any compression requirements

Now that we understand some common reasons why a seal might fail, let’s look at how to improve an O-ring seal.

Ways to Make an O-ring Seal Better

O-rings are used in various industries, including aerospace, agriculture, plumbing, and transportation, to name but a few. These common ring-shaped seals fit into couplings, engines, pipes, pumps, shafts, and valves in various mechanical equipment. They’re used to prevent fuel, lubricants, oils, refrigerants, steam, water, and other liquids or gases from escaping. Understanding how to make an O-ring seal better starts with the installation process and, when done correctly, saves businesses time and money on maintenance and repair.

Many seal failures result from improper O-ring installation. To function properly, they must be free of foreign material and fitted correctly without forcing, while lubrication and added tape covering help extend the O-ring’s life. Correctly installed O-rings prevent leaks and lengthen the life of other components, whereas when poorly installed, they lead to damaged equipment and downtime, as well as additional maintenance and repair. To properly install an O-ring and ensure its proper functioning, a few guidelines should be followed.

Guidelines for how to make an O-ring seal better:

• Don’t stretch an O-ring excessively to prevent snapping or tearing once assembled.
• Ensure the O-ring is correctly sized; if it’s too small, the O-ring will break or tear, while if it’s too big it won’t provide an adequate seal.
• Mate O-rings with threaded parts, avoiding tears and nicks by wrapping masking tape around threads and lubricating O-rings so they slide easily into place.
• Slide O-rings onto shafts rather than rolling them, which will cause them to spiral and limit their functionality.
• Thinly coat O-ring surfaces with lubricant to increase functionality and extend its operational life, filling spaces and gaps where mated parts join with the O-ring.
• Care should be taken during installation when working around corners and sharp edges to avoid tearing or nicking while lubricating the O-ring will help it slide more easily into place.

As per many of these guidelines, lubrication is particularly useful in improving O-rings seal.

Using Lubricant to Make O-rings Seal Better

To properly function, O-rings must be lubricated. Not only will lubrication help the seal last longer, but it will also prevent breakdowns of machinery, motors, engines, or other devices the seal is meant to protect should it fail. Applying oil or grease will protect the O-ring from damage when used. Lubricants also protect components by minimizing friction, providing water resistance, or preventing environmental degradation. Lubricating O-rings also reduces the chance of leaking seals in vacuum or pneumatic applications.

There are three main methods for lubricating an O-ring: 

• Applying lubricant directly and evenly on the O-ring with a brush or fingers.
• Dipping an O-ring directly into a lubricant-filled container.
• Dispensing lubricant directly into the O-ring’s packaging and spreading it evenly.

Various lubricants can be used when installing O-rings, with solvents, soap, water, polymers, petroleum distillates, and ester-based synthetic oils being the most commonly used. Some of these lubricants have led to concerns regarding safety and health, however, while certain lubricants can also damage rubber O-rings. Solvents contain volatile organic compounds (VOCs) that pose risks to human health while also posing a fire risk. Though soap and water are safer, their lubricating properties are inconsistent, and these solutions don’t work well in wet or damp environments. Meanwhile, any petroleum-based lubricants cause elastomeric rubbers to dry out or swell.

Since most O-rings and seals are made from synthetic rubber-like material such as ethylene propylene diene monomer (EPDM) rubber, neoprene, or nitrile, they’re best lubricated with other synthetic compounds. Ester-based and silicone-based lubricants top this list. Their properties include reducing friction, low volatility, stability in high temperatures and fluidity in lower temperatures, and waterproofing. Both synthetic lubricants are safe, posing neither risk of contamination nor health, and are also usable with products containing natural rubber.

As O-rings are used so widely, it’s important to be installed and maintained properly to function as designed. This includes ensuring they remain free of foreign substances and that they’re properly lubricated. By ensuring proper installation and maintenance, O-rings will continue to play a vital role in the operation and fabrication of appliances, aircraft, automobiles, engines, machinery, medical devices, motors, plumbing, pumps, and trucks, along with many other modern devices and equipment on which modern civilization depends.