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When choosing a seal for your operation, it’s hard to decide which company has the best. At Real Seal, we routinely put our seals through strenuous ASTM testing to ensure consistent quality. ASTM is an international standards organization that originated in the USA as a way to hold manufacturers to a higher standard of quality and reliability. By employing these standards, Real Seal is able to prove the durability of our seals to a variety of elements. Various tests designed by ASTM to ensure this level of quality include these various properties and more:
Compression Set
Compression set is how deformed a material becomes after a certain amount of force is applied to the material. This is especially important for seals so that as they undergo the various pressures of sealing, they are able retain the shape necessary for sealing the surface they are adhered to.
ASTM D395 is one of the most common methods of testing for compression set. There are two methods under this protocol. Method A tests compression as the percentage of thickness of an object, in this case the seal, after being exposed to a constant force for a set time and temperature, then giving it thirty minutes to recover. In method B, the material is compressed by 25% and then a measurement is taken. Both of these methods allow for the seal to be tested for its ability to reform after being compressed by a force.
Hardness
Another important factor in how durable any given seal is the hardness of the seal. The harder the seal, the more resistant it is to impact, as well as being able to maintain its form better, although harder materials can crack or break.
ASTM D2240 uses a durometer to determine the hardness of rubber and plastic materials used to make o-rings and other seals. This test is done by measuring how much a material is penetrated or “pushed in” by a specified indenting implement. Hardness is drawn from a scale known as Shore hardness; Shore A for softer materials, and Shore D for harder materials.
Heat Resistance
Many industrial applications of seals put the material under the intense strain of heat. Heat can warp and damage the material over time if it isn’t chosen correctly or of the highest quality.
ASTM D573 tests the effects of increased temperature on a seal. The seal is placed in a hot oven or other heating device and then the hardness, elasticity, or other materials are then tested. Any changes in these properties can indicate deterioration of the material. These tests are often specified to the conditions a given application will place upon the seal, ensuring that it won’t degrade too quickly and cause some kind of catastrophic failure.
Tear Strength
Perhaps one of the most important properties for dynamic operations is the tear strength of a material. The tear strength of a material is its ability to resist being torn apart by a force. Damage by heat, friction, and other forces can lower the tear strength of a material, so those aspects are important, as well.
ASTM D624 sets the standards for testing a material’s strength divided by its thickness at resisting forces pulling it apart with a nick to lead the tear. A tensile test machine is clamped to two ends of the material and then pulls. The maximum force required to tear the material is used to determine this property.
Fatigue Limit
Fatigue limit is another important property for dynamic operations with cyclic motion. A material’s fatigue limit is its ability to withstand the stress of undergoing this kind of cyclical strain. This is best tested by applying the same type of force which will be applied to the seal during its operation for a certain number of cycles to see if there are any tears or changes its properties such as tear strength and hardness.
Real Seal’s Commitment
Real Seal is committed to testing and ensuring that a product will withstand the pressures it will undergo during operation. ASTM and ISO guidelines ensure that their seals will be put under the right amount and type of strain to maintain a superior product. To ensure that the seals you use for your operations are durable and of the highest quality, contact Real Seal today!
How Mechanical Seals Make Workplaces Safer
There are many hazards in industrial operations, so it’s best to use the safest option available when it comes to equipment. Sealing your machines is no different. Traditional gland packing inevitably leaks and requires constant attention. On the other hand, mechanical seals are able to reduce leakage to a near zero number. There are a wide range of reasons why mechanical seals are the superior option:
Reduced Leakage
The first concern of any sealing system is: does it leak? With mechanical seals, there should be virtually no leakage. When the correct seal is chosen, accounting for all the variables in an operation, it will withstand the forces acting upon it.
Why is leakage a problem? Many products being forced through machinery have extremely toxic properties for humans and the environment. Reducing leaks to a near zero number is paramount to the health of those working around the machinery and the surrounding environment. Fumes can have a similar effect and sealing systems can be made to be air-tight. Some chemicals are so toxic that even a small amount can be harmful, so any level of leakage is unacceptable.
Toxicity isn’t the only concern when it comes to how safe a fluid is. Flammable fluids can cause major damage to an operation if they ignite, not to mention the potential loss of life. Extremely acidic or basic solutions can damage equipment and personnel, as well.
With gland packing, there is always a certain amount of product loss and it can gradually pool up on the floor or other surfaces, with cleaning itself becoming a hazard if the product is unsafe. Slipping can become a real hazard, especially when workers are rushing around trying to work as quickly and efficiently as possible. Accidents should be prevented in every possible way.
Less Maintenance
Traditional gland packing requires continual upkeep as the packing wears down over time. This requires maintenance staff to always be checking and fixing the packing, leaving them exposed to the product. If the machine has moving parts, then it becomes an even more dangerous exercise. Pinched digits and limbs, crushing, and even amputation can occur if machinery is powerful enough; so having mechanical seals that require less frequent maintenance requirements limits exposure to such dangers.
Prevents Wear
Mechanical seals also reduce friction between mechanical parts and are superior to gland packing, which are notorious for increased friction. This constant rubbing can lead to catastrophic failure and dangerous situations. Dual mechanical sealing systems can be installed to create a fail safe environment should the first seal rupture.
Some Tips to Keep your Seals Safe
While mechanical seals are the safest option, it is also necessary to keep an eye on them to make sure they aren’t wearing. Regularly assessing the various elements of an operation to ensure they aren’t outputting more strain than they should be is essential. If you notice that a seal is beginning to leak or allow fumes to escape, it’s vital to replace the seal as any amount of leaking can indicate that it is wearing and could fail, or that it has uncoupled from its surfaces.
Use an Expert
To ensure that your operation and the seals you use in it are the safest possible, you should use an expert company for product and consultation. Real Seal is a leader in the sealing industry. Contact Real Seal today to make your place of work the safest it can be!
7 Machinery Maintenance Tips for Any Industry
Machines wear down over time; it’s inevitable with the amount of wear they undergo just doing their job. Moving parts, caustic fluids, and the force of time and nature all take their toll. The best way to make your machines work longer and harder for your operation is maintain them regularly, ensuring they last as long as possible, saving money, and reducing downtime. Here are some tips to consider:
1: Lubrication
Friction is one of the most constant forces wearing on your machinery. Proper lubrication is key when it comes to machine maintenance, as it reduces the degradation of equipment. Lubrication also makes it so your machines don’t have to work as hard, further reducing wear, as well as energy costs from machines that are working beyond their optimal limits.
2: Cleanliness
It’s hard to keep machines clean, especially in industrial settings. A clean machine isn’t just an aesthetic improvement. Contaminants from dirt and other residue buildup can pose a major problem: jamming parts, increased friction, and more. They can also contaminate product. A clean machine is less likely to rust, which can help prevent long term damage to equipment and possible outright mechanical failure.
3: Testing
Often machines are composed of multiple working parts with their own operating ranges, not to mention entire groups of machines working together. It’s important to regularly test each component of a machine or group of machines to make sure they are all working as they should: maintaining proper heat, speed, pressure, and other important variables. When one part of a machine, or collection of machines, begins to fail, it can cause a chain reaction of issues. So nipping smaller problems in the bud can really cut down on the potential of larger issues.
4: Alignment
Another key variable for machines is the alignment of various parts. When a part isn’t properly aligned, it can cause a machine to break down much more quickly as it isn’t exerting its forces properly, causing damage to parts not designed to bear the amount of said force. Misaligned parts can cause increased vibrations, which will increase heat and friction.
5: Keep a Schedule
It’s imperative to regularly perform all of the necessary maintenance on your operation’s machines. A schedule, whether physical or digital, can be a great way to ensure it’s being done. Include a checklist of each step for every machine so nothing is missed. If possible, it’s a good idea to occasionally rotate who is doing the inspections if there are multiple qualified personnel, as a different set of eyes will see different problems and might catch something another person might’ve missed.
6: Components
While it’s easy to remember to check a machine, sometimes it can be hard to remember that components play an equally vital role to a machine’s function. Always inspect such essential pieces of the operation, because when they fail the rest of the machine can fail, as well. Each component will have its own unique set of needs.
For example, seals are extremely vital to any operation where fluid is flowing through a system. Check seals for signs of leakage regularly, as this can be an indication of a possible impending failure and that the seals should be replaced. Making sure that your machine is operating within its limits is also important to ensure that components, such as seals, will perform as designed; many components can only function within a certain range of conditions and will fail when pushed beyond those points.
7: Consult the Experts
Often, when dealing with components, it’s hard to know all you need to in order to ensure that they aren’t going to fail and will be maintained properly. Contacting an expert can save your operation from an inevitable large scale issue. Real Seal is an expert in seals and can help with any of these issues. Contact us today!
What are the Practical Benefits of Polyurethane O-Rings?
If your application requires a material with outstanding physical durability, polyurethane o-rings are the way to go. Polyurethanes, also known as urethanes, derive their unique benefits and advantages through their unique structural bonds. These bonds are unique because of their combinations of soft polyol segments and tough isocyanate segments, creating a flexible but still durable material. There are a variety of types of polyurethane for all kinds of applications.
Types of Polyurethane
Just like all types of materials, polyurethane comes in different types, each with their own benefits and applications. The most common of these varieties is polyester with most urethane seals being based on polyester. Polyester based o-rings are resistant to hydrocarbon oils and hydraulic oils.
Two additional types of polyurethane are polyether based and polycaprolactone based rings. Polyether based o-rings have the advantages of being better for hydrolytic stability and being functional at lower temperatures. Polycaprolactone based o-rings are a subgroup of polyesters with a portion of the low temperature capabilities and oil resistances of the aforementioned polyether rings.
Curatives
Another customizable advantage of polyurethanes is the cure which is used on the o-ring, giving additional properties to the urethane. Similar to other elastomers, millable gum urethanes use the more standard peroxide and sulfur cure systems. Higher performing thermoplastics and thermosetting materials use isocyanate curing systems.
MDI is one of the most common curatives and most often used in thermoplastic materials, as well as millable gum urethanes. MDI is safer for the environment than other diisocyanates.
TODI increases heat resistance and mechanical properties. PPDI has the highest of heat resistances and is best used in applications with hot temperatures.
Properties
Polyurethanes have a wide range of properties with many different advantages and benefits. Hardness can be controlled for whatever the application requires. For applications requiring a high load bearing capacity, polyurethanes are able to return to their normal shape and form after being compressed with minimal damage. Flexibility is also a key benefit of polyurethanes with a wide range of motion and the strength to resist breakage. Durability is a key advantage of polyurethanes, being resistant to tearing and abrasion.
When insulation against various elements is a concern, polyurethanes perform. Electricity, wetness, and various temperature ranges can all be managed with different types of polyurethanes and cures. If your application requires the polyurethane ring to be bonded, that is also something this material can be designed to do, being able to adhere to wood, plastic, or metal.
If contamination of food or other sensitive material is a concern, polyurethanes are sterile against various fungi including mold and mildew.
Generally, polyurethane o-rings have cheaper tooling than plastic, making it a more cost effective option. Polyurethane o-rings are also better at resisting radiation than plastic.
When it comes to advantages of polyurethane over metal, durability is key. Rigid materials wear down faster and can’t conform as easily. Polyurethane o-ring are also quieter and don’t create sparks like metal does. Plus, they don’t rust.
Finding the Right Polyurethane O-Ring
When considering the various types of polyurethane o-rings, it’s best to consult an expert in the field. No matter the design challenges, Real Seal is up to the task. Contact Real Seal today for any questions you have regarding polyurethane o-rings.
The Integral Role Seals Play in Engineering and Design
Engineering and designing of any kind is filled with variables. Any process that requires a seal to ensure that no fluid or material escapes has its own set of unique design challenges. When designing a system, it’s important to remember every force and factor acting upon the seal, otherwise it could lead to catastrophic failure.
Product Pressure
With any application of a seal, pressure is a concern. If the wrong seal is chosen, pressure can cause product to escape. Under extreme pressures, if the seal is incorrectly chosen, it will simply break and cause complete failure. A seal should be able to withstand the entire range of pressures a system may undergo during different phases and with shifting loads. As pressure increases, the fluid film becomes thinner (this means more friction on the seal) – and the inverse is true, as well; lower pressure means a thicker film.
When prototyping, it’s important to run at the highest ranges so that you know exactly what ranges are required of your seals. The seal should be able to withstand the peaks and valleys of the system. High pressure systems need to be extremely vigilant about maintaining a tight seal, as contaminants have a much higher impact upon these systems due to their higher velocity, thus increased friction and damage.
System Load
Seals must be able to withstand the forces of the system that they are sealing. In order to maintain alignment and proper guidance of the piston, rod, or other moving part, it is essential to choose a seal with a high enough load bearing capacity. When prototyping, it’s important to factor in the entire force of the application, not just isolated pieces. The cumulative effect of a system can be much higher when put together and not just piece by piece.
Temperature
The temperature of a seal comes from a myriad of places including: product, environmental conditions, and friction. Simply knowing how much heat a system outputs is not enough. It’s vital to know the entire set of factors when selecting a seal. The range of temperature is also important to consider, as a high variance will alter the seal’s ability to maintain its shape.
High heat, of course, deforms and melts seals, but low temperatures also have negative impact upon the seal. Always account for environmental conditions when it comes to seals, especially for outdoor applications: rain, snow, or intense heat are all going to have an effect on the seal and the system it is attached to, requiring a wide range of temperature tolerance. Again, it is not enough to have just the isolated pieces tested; the entire system must be taken into account when it comes to heat.
Velocity
The speed at which any given system operates is a huge factor in sealing. Not only does it affect the wear and tear of a seal, but also the temperature due to friction. Fluid properties can also be altered during speed changes and high speed environments, causing alterations in the fluid film. Systems that have a variance of speed can undergo rapid changes in pressure or temperature, requiring durable seals with high ranges of tolerance.
Chemical Properties
Perhaps the most specialized area of sealing is the various chemical requirements of different systems. Some seals will wear down when exposed to acids, oils, and all kinds of chemicals. Just because a seal is solid doesn’t mean it can’t have a reaction with the fluid it is housing. Also, seals must be able to keep out any unwanted contaminants; some products simply can’t have water enter the system, while others need a barrier against biological contaminants.
Expertise
When it comes to design and engineering, seals play an integral role; if only one of these many factors aren’t taken into account, catastrophic failure can occur, causing major loss in product and damage to machinery. Make sure to work with an expert in sealing and the materials seals are made of when designing any system. Real Seal has years of experience designing solutions for all kinds of applications. Contact Real Seal today to ensure your systems are properly sealed.
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