How to Improve the Leakage of Rubber Seals?

Before learn how to improve the leakage of rubber seals, we should know some basic knowledge about this item:

1. The characteristics of rubber seal material:

(1) Viscoelasticity

The material of rubber seals is affected by temperature and time during deformation and deformation recovery, resulting in the stress relaxation and creep phenomenon of the material specification of rubber seals. Under the action of vibration or alternating stress, hysteresis loss occurs.

(2) High elasticity

The seals can maintain elasticity specification at a certain temperature due to its recoverable deformation. If its elastic modulus is low, its elongation deformation is large.

(3) There is aging phenomenon

Such as metal corrosion, wood decay, rock weathering, the rubber will also face its problem due to environmental changes and aging phenomena. So the sealing performance will be reduced, life declines.

(4) Vulcanized

It must be vulcanized before use, except for thermoplastic elastomer.

(5) Electrical insulation

The same as plastic, rubber is also a electrical insulation material.

(6) Have to add the compound

Small specific gravity, low hardness, good softness, good air tightness and other characteristics, all belong to the rubber performance

2. Physical and mechanical properties

(1) Fixed-elongation stress:

Also known as fixed-elongation strength, refers to the load borne by the sample per unit area when it is stretched to a certain length. The unit of measurement is the same as the tensile strength, which reflects the strength of the rubber material’s resistance to external deformation.

(2) Tear strength:

The load borne by the unit thickness when tearing the special test piece (with cutting or rectangular shape), which indicates the anti-tearing property of the material.

(3) Tensile strength:

Also known as tensile strength and tensile strength, refers to the load on the unit section of the test piece when it is stretched to fracture.

(4) Permanent deformation:

After the specimen stretched to fracture, the percentage of the non-recoverable part of the standard elongation deformation in the original length.

(5) Hardness:

It refers to the ability of rubber to resist external pressure. It is usually measured by the Shao Er durometer. The hardness range of rubber sealing material is generally between 20 and 100, the unit is Shaw A.

(6) Elongation:

When the specimen is broken, the ratio of the elongation to the original length is called elongation and is expressed in percentage.

(7) Resilience:

Also known as impact resilience, refers to the ability of rubber to recover to its original state after being impacted, expressed in percentage.

3. Some methods to improve the leakage of rubber seals

(1) Mold quality

To save time and cost, more and more sealing parts manufacturers would like to choose the cheaper one and can shorten the time as well. You get what you pay off. It determines the accuracy of the mold will not be high, the quality of products will not be particularly good.

(2) Selection of materials

There is a lot of material that can be used to produce rubber sealant. Which one we should choose to depend on the application of the products. It requires us to know its use environment and requirement. And it is necessary to understand the various features of the materials very well at the same time. In addition to the general requirements for sealing ring materials, the following conditions shall be noted at the same time:

(a) Full of elasticity and resilience;
(b) Appropriate mechanical strength, including expansion strength, elongation and tear strength, etc.
(c) Stable performance, not easy to swell in the medium, small thermal shrinkage effect (Joule effect).
(d) Easy to process and shape, and can maintain precision size.
(e) Do not corrode the contact surface, do not pollute the medium, etc.

The most suitable and most commonly used material to meet the above requirements is rubber, so the sealing ring is mostly made of rubber material.
There is various rubber, and there are new varieties of rubber, design, and selection. We should understand the characteristics of all kinds of rubber, and make reasonable choices.

How to choose the material of the rubber seal?
Each rubber material has its own advantages and disadvantages, and each rubber can be formulated according to different performance requirements.
In the design process, how to choose the right rubber seal material according to the actual situation is very important.
How to choose the material of the rubber seal? We should start with the following aspects:

(a) First of all, it is necessary to consider the substances that the rubber seal needs to touch, in addition to paying attention to whether the rubber seal material can withstand the sealed fluid, such as air, water, oil, steam, and so on.
Attention should also be paid to metal or plastic parts in contact with rubber seals.
For example, if an unsuitable rubber piece is placed with a polycarbonate plastic for a long time, some components of the rubber piece will slowly seep into the contact surface of the two pieces, causing the polycarbonate plastic surface to crack.
 
(b) In many cases, the rubber seal is used for the main function of waterproof, but then add disinfectant residue in water or other medium is an important consideration, the disinfectant or medium in the water can react with rubber seals, rubber swelling deformation, even decomposition, which affect the rubber sealing function of seal and longevity.
 
(c) Other factors in the use environment, such as long-term contact with ozone (ozone resistance), use temperature, etc., the temperature resistance of different materials is also different.
 
(d) In addition to the above factors, also need to consider the rubber seal tensile strength, under pressure, etc.
 
The above list is just a few common important factors, each product design or application has its own particularity, designers should be based on the specific analysis.

(3) Strict production process

After doing the first two steps extremely well, the production aspect becomes crucial.

These three steps are the key. But it can not eliminate the leakage problem. We also should pay attention to the storage environment, which will also affect the leakage of rubber seals.

(4) Storing Properly

(a) Store in a cool place, but not in direct sunlight. Ultraviolet rays and moisture will accelerate the deterioration of rubber and cause size changes.
(b) Do not open the sealing package unless we use it, to avoid dust sticking or scratch the sealing.
(c) When storing unpacked products, do not stick or bring in impurities on the product, and store them in the original state.
(d) Seals should not be placed near the heat source, motor, or ozone production place.
(e) Do not use wire, rope hanging seals. If storage in this way, it will make the seals deformation, damage the lip mouth.

(5) Installation Correctly

(a) Before the seal installation, to check the cylinder head groove and piston steps, groove surface roughness, no acute Angle, burr, collision. Check the bottom diameter tolerance zone of the main seal groove. The groove size and accuracy shall conform to the geometric standard requirements of the seal. The groove width of the guide belt should be closely matched with the guide belt without any loose defects. Ensure that the sealing parts slip into the chamfer dimension length and roughness. Ensure that metal edges and corners do not cause any damage to the seal during the installation process.
(b) The cylinder seal installation requires a clean environment, ensure that the assembly is installed clean, installation, pay attention to identify the seal orientation, avoid installation direction error resulting in assembly failure. When sealing parts are installed in the groove, do not use metal tools to prevent damage to the surface of sealing parts.
(c) when installing seals, can only apply a small amount of grease on the metal surface, to facilitate the installation, but rubber elastic and sliding sealing ring must be oil-free assembly, grease residue on the surface of seals, will affect the sealing performance.
(d) If it is a vertical or horizontal installation should keep the piston and cylinder coaxial, too much eccentric will damage the seals. When the piston is assembled for a cylinder with internal thread, guide sleeve assembly must be applied. When assembling a vertical oil cylinder, the piston rod should not fall freely after the piston enters the cylinder, because the sealing element will be damaged if the speed is too fast.

Rubber seals are essential components in a wide variety of applications, from automotive engines to industrial machinery, plumbing systems, and even household appliances. These seals act as barriers to prevent leaks, protect against contaminants, and maintain pressure within a system. However, like any other material, rubber seals are subject to wear and tear over time.

To maximize the longevity of rubber seals and ensure optimal performance, proper maintenance is key. In this blog, we’ll explore practical tips to help you maintain your rubber seals and extend their lifespan.

1. Keep Seals Clean and Free of Debris

Dirt, dust, and other contaminants can accumulate on rubber seals over time, leading to premature wear or damage. Regularly cleaning your seals is one of the simplest yet most effective maintenance steps you can take.

How to Clean Rubber Seals:

• Use a soft cloth or sponge with mild soap and water to wipe down the seals.
• Avoid using harsh chemicals, solvents, or abrasive materials that can degrade the rubber.
• Ensure that you thoroughly dry the seals after cleaning to prevent moisture buildup, which can lead to mold growth or cracking.

2. Lubricate Regularly

Lubrication helps reduce friction between the rubber seal and the surfaces it contacts. It also helps maintain the seal’s flexibility and prevents it from drying out, cracking, or becoming brittle.

How to Lubricate Rubber Seals:

• Use silicone-based lubricants or a rubber-friendly grease specifically designed for seals. Avoid petroleum-based lubricants, as they can cause the rubber to deteriorate.
• Apply the lubricant evenly across the entire surface of the seal.
• Wipe away excess lubricant to avoid attracting dirt and debris.

3. Inspect Seals for Wear and Tear

Regular inspections are crucial for catching early signs of wear, cracks, or damage that could compromise the seal’s performance. This is especially important in applications where rubber seals are exposed to extreme temperatures, pressure, or chemicals.

What to Look For:

• Cracks or cuts: These can occur due to exposure to harsh environments or aging.
• Flattening or compression set: Over time, rubber seals can lose their original shape, reducing their effectiveness.
• Discoloration: This could be a sign of chemical degradation or UV exposure.

If you notice any significant damage, it may be time to replace the seal.

4. Protect Seals from Extreme Temperatures

Rubber seals can become brittle and crack when exposed to extreme cold or soften and degrade under high heat. To maximize the lifespan of your seals, ensure that they are operating within their specified temperature range.

Tips for Temperature Management:

• For applications involving high heat, choose seals made from heat-resistant materials like Viton or Silicone.
• In cold environments, use seals made from EPDM or Nitrile for better flexibility at low temperatures.
• If possible, insulate or shield the seals from direct exposure to heat or cold to reduce temperature fluctuations.

5. Avoid Exposure to Harmful Chemicals

Many rubber materials can degrade when exposed to certain chemicals, such as oils, fuels, solvents, or harsh cleaning agents. It’s essential to choose the right rubber material for your specific application and minimize exposure to chemicals that could damage the seal.

How to Minimize Chemical Exposure:

• Consult the seal manufacturer for guidance on the best material for your application. For example, Nitrile rubber is excellent for oil and fuel resistance, while EPDM is ideal for resisting water and chemicals.
• Store rubber seals in a clean, dry environment away from chemical fumes or vapors.

6. Ensure Proper Installation

Incorrect installation can lead to misalignment, over-compression, or pinching, all of which can shorten the lifespan of rubber seals. It’s important to follow the manufacturer’s installation guidelines and ensure that seals are fitted correctly.

Best Practices for Installation:

• Make sure the surfaces where the seal will be placed are clean, smooth, and free of debris.
• Avoid overstretching or twisting the seal during installation, as this can cause tears or deformation.
• Use appropriate tools and follow torque specifications to prevent over-compressing the seal.

7. Store Seals Properly When Not in Use

Rubber seals that are not in use should be stored in a controlled environment to prevent premature aging. Exposure to sunlight, oxygen, and ozone can degrade rubber materials over time.

Storage Tips:

• Store seals in a cool, dry, and dark environment, away from direct sunlight and sources of heat.
• Keep them in airtight containers or vacuum-sealed bags to limit exposure to oxygen and ozone, which can cause rubber to crack or deteriorate.
• Avoid storing seals near electrical equipment or motors that produce ozone.

8. Replace Seals When Necessary

No matter how well you maintain your rubber seals, they will eventually wear out and need to be replaced. Continuing to use damaged or worn-out seals can lead to system failures, leaks, or contamination.

Signs It’s Time to Replace:

• Significant cracking, hardening, or deformation of the seal.
• Loss of elasticity or flexibility.
• Persistent leaks or reduced performance even after maintenance.

Proactively replacing worn seals can save you from costly downtime and repairs.

Conclusion

Proper maintenance of rubber seals is essential for ensuring their longevity and optimal performance. By following these tips—regular cleaning, lubrication, inspection, and protection from environmental factors—you can extend the life of your seals and prevent system failures.

At Accuseal Rubber Inc., we specialize in high-quality rubber seals designed for a wide range of applications. Our products are engineered to withstand harsh conditions, and with the right maintenance practices, they can provide years of reliable service. If you need assistance with choosing the right seal or want more maintenance advice, contact our team of experts today.